The 28th and last flight (STS-107) of the space shuttle Columbia was ten years ago. Launched on January 16, 2003 Columbia was destroyed at about 0900 EST on February 1, 2003 while re-entering the atmosphere after its 16-day scientific mission. The destruction of the shuttle killed all seven astronauts on board.
The traditional “in-flight” picture of the crew. This picture was taken from a camera recovered from the crash debris. Photo credit NASA.
An illustrious career
Columbia was the first of the space shuttles to fly, it was successfully launched on April 12, 1981, the 20th anniversary of the first human spaceflight by Yuri Gagarin in Vostok 1, and returned on April 14, 1981, after orbiting the Earth 36 times. The first flight of Columbia (STS-1) was commanded by John Young, a Gemini and Apollo veteran who was the ninth person to walk on the Moon in 1972, and piloted by Robert Crippen, a rookie astronaut who served as a support crew member for the Skylab and Apollo-Soyuz missions.
Columbia has an illustrious career as part of the US space program, featuring many ‘firsts’. It was the first true manned spaceship. It was also the first manned vehicle to be flown into orbit without benefit of previous unmanned “orbital” testing; the first to launch with wings using solid rocket boosters. It was also the first winged reentry vehicle to return to a conventional runway landing, weighing more than 99-tons as it was braked to a stop on the dry lakebed at Edwards Air Force Base, California.
NASA PHOTO: The April 12, 1981 launch at Pad 39A of STS-1, just seconds past 7 a.m., Columbia carries astronauts John Young and Robert Crippen into an Earth orbital mission scheduled to last for 54 hours, ending with unpowered landing at Edwards Air Force Base in California.
Its second flight, STS-2 on November 12, 1981 marked the first re-use of a manned space vehicle. A year later it became the first 4-person space vehicle – bumping this to six on its sixth flight (STS-9) on November 28, 1983. This flight also featured both the first flight of the reusable laboratory ‘Spacelab’ and the first non-American astronaut on a space shuttle, Ulf Merbold. STS-93, launched on July 23, 1999, was commanded by Eileen Collins, the first female Commander of a US spacecraft.
Space Shuttle Columbia flew 28 flights, spent 300.74 days in space, completed 4,808 orbits, launched 8 satellites and flew 201,497,772 km in total, including its final mission. Its penultimate flight (STS-109) was the third of the highly publicised servicing and upgrade flights to the Hubble Space Telescope.
The fatal flight
The rockets fire. Amidst the thundering fiery roar the shuttle lifts majestically from the launch pad. Unnoticed at the time, at 81.9 seconds after launch a foam insulating block disintegrates upon hitting the leading edge of the shuttles left-wing. The launch continues as scheduled. One hour after launch Columbia was in orbit and the crew began to configure it for their 16-day mission in space.
The next day, routine analysis of high-resolution video from the tracking cameras reveals the debris strike. Multiple groups within the mission team review the tapes. They assess the possibility of damage and decide that an image is required of the wing. They make a request to the NASA ground management for imaging of the wing in-orbit.
However, it was considered “of low concern” that the carbon matrix could be damaged by the foam block. The engineers were over-reacting. The Space shuttle Program managers declined to get the Columbia imaged – or alert the shuttle crew. In fact the crew were told that the impact was a “turn-around issue”, something they had seen before and would be a maintenance check only. Titanic-like the mission continued.
Scientifically the mission was great success. The shuttle crew worked around the clock to ensure that maximum scientific value was achieved. Including an investigation of the web-spinning abilities of the Golden orb spider under low gravity. An experiment designed by students from Glen Waverley Secondary College, in Melbourne Australia.
The morning of re-entry all appears calm and normal in the mission control room. As re-entry started the crew are seen to be in good spirits and looking forward to coming home.
Then while travelling at Mach 24.1, during the 10-minute fiery re-entry, when the leading edge reaches temperatures in excess of 1550 Celsius, the damaged thermal protection panels on the wing overheated – then failed catastrophically. The wing and shuttle disintegrating.
The nearly 84,000 pieces of debris from the shuttle are stored in a 16th floor office suite in the Vehicle Assembly Building at the Kennedy Space Center.
Two other died in the search for the debris: Jules Mier (Debris Search Pilot) and Charles Krenek (Debris Search Aviation Specialist).
NASA PHOTO: Final descent, Columbia streaking over the Owens Valley Radio Observatory in Big Pine, California
Is spaceflight perilous? Or an unforgiving adventure?
It is rather remarkable that NASA had launched men into space sixteen times during the the Mercury and Gemini programs without a casualty – although there had been some scary moments.
Compared to the cramped and tiny Mercury capsule the Apollo command module was, in spaceflight terms, a luxury liner. So when a spark ignited the oxygen atmosphere of the Apollo 1 capsule on January 27, 1967 killing three astronauts it was shocking for both NASA and the public. The last communication from the Apollo 1 capsule was not revealed for a long time to the public:
Fire! We’ve got a fire in the cockpit! We’ve got a bad fire…..get us out. We’re burning up…..
The last sound was a scream, shrill and brief. After this nothing at NASA would be quite the same again.
The fatal Apollo 1 fire was also unexpected. At the time of the fire the crew of Gus Grissom, John Young and Roger Chaffee were perched atop an empty Saturn V rocket involved in routine testing of the capsule control systems.
The 1986 Challenger disaster was equally shocking – and far more public. The explosion 73 seconds after lift off claimed shuttle crew and vehicle. The cause of explosion was determined to be an o-ring failure in the right solid rocket booster. Cold weather was determined to be a contributing factor. The subsequent investigation and changes delayed the next shuttle launch to late 1988.
Space Shuttle Challenger’s smoke plume after its in-flight breakup, resulting in its crash and the deaths of all seven crew members. Photo credit NASA.
You could say that space exploration in itself is not inherently dangerous. But to an even greater degree than aviation, it is terribly unforgiving of any carelessness, incapacity or neglect. Gus Grissom has been quoted as saying during the pioneering Mercury missions:
If we die we want people to accept it. We hope that if anything happens to us it will not delay the program. The conquest of space is worth the risk of life.
I’m not sure that Gus Grissom would have accepted these deaths as an acceptable risk of human spaceflight.
Apollo 17 Commander, Eugene Cernan, next to the lunar rover. Image credit NASA.
After kangaroo hopping back to the lunar rover, Eugene and Jack drove back to the lunar module, Challenger. There they dusted each other off and loaded the last of their 100kg of lunar rock samples. Jack cleaned up inside While Eugene parked the rover a kilometre and a half away so the takeoff could be televised. Then hopping and skipping in the low lunar gravity he made the most of his last moments on the moon. Once back at the lunar module, one foot on the Challenger’s landing pad, Eugene Cernan lifted his other from the moon, and said:
As I take these last steps from the surface for some time to come, I’d just like to record that America’s challenge of today has forged man’s destiny of tomorrow.
The next day, December 14, 1972, they blasted off from the moon, ending the sixth and last human exploration of the moon for the 20th century.
The last of the lunar Apollos
The Apollo program was a child of the cold war between the USA and Soviet Russia. It was invigorated by President Kennedy’s 1961 challenge to put man on the moon and return him safely before the decade was over. Once the landing of Apollo 11 was achieved in July 1969, the Apollo and NASA budgets came under savage scrutiny. It was the time of the war in Vietnam, budget problems for the 1972 fiscal year and followed the scare of Apollo 13.
The final two scheduled Apollo missions, 18 and 19, were finally cancelled in September 2, 1970. Apollo 20 had already been cancelled on January 2 so that its Saturn V rocket could be used as the launch vehicle for the Skylab space-station in 1973.
The first part of the return journey as the Lunar module, Challenger, approaches Apollo 17 Command Service Module, America, after blasting off the lunar surface. Photo credit NASA
The Apollo program was an incredible, successful human feat. It remains the only program to have placed humans beyond low-earth orbit and onto another celestial body. Apollo 8 was the first manned spacecraft to orbit another celestial body, while Apollo 11 landed the first humans on another world. The program returned 382 kg of lunar rocks and soil to Earth, contributing to the understanding of lunar geology.
It laid the foundation for NASA’s current human spaceflight capability, and funded construction of its Johnson Space Center and Kennedy Space Center. Apollo also spurred advances in many areas of technology incidental to rocketry and manned spaceflight and the start of huge opportunities for technology transfer, leading to more than 1,500 successful spinoffs related to areas as disparate as heart monitors, solar panels, and cordless innovation. More recently, we’ve seen a fledgling private-sector American space industry complete its first cargo delivery to the international space station.
Stepping up, walking tall
There is a marvelous fascination with human exploration. The Apollo missions are a great representation of that drive and curiosity. Apollo 17 astronauts, Eugene Cernan, Harrison Schmitt and Ron Evans, exemplified those attributes.
Publicity shot of the Apollo 17 crew with their Saturn V vehicle in the background. (L-R): jack Schmitt, Eugene Cernan (seated) and Ron Evans.
Eugene Cernan is ‘Captain America’ to a tee. A US Navy pilot who, like much of America, was caught up in the early space race. In 1962 he watched, captivated, on TV the launch of John Glenn. Who in the third manned Mercury capsule became the first American to orbit the earth. Cernan at the time lacked the coveted ‘test-pilot’ wings to be selected in the September 1962 second group of astronauts, which included Apollo 11 commander, Neil Armstrong. Cernan was picked, in October 1963, for the third astronaut group – which included the other Apollo 11 astronauts Buzz Aldrin and Michael Collins.
Cernan became the second American astronaut, after Ed White on June 3 1965, to perform an extra-vehicular activity – a spacewalk. His Gemini 9 spacewalk lasted 2 hours and nine minutes, travelling 57,600 km, and rated as one most difficult achievements of his life. The brutal mechanics of Newton’s third law in action in space making seemingly simple tasks into exhausting and challenging experiences, resulting in fogging his helmet and pushing his heart rate to 188 bpm. His experiences made NASA rethink the training required for future extra-vehicular activities.
Gemini 9 splashdown with Eugene Cernan (L) and a smiling Tom Stafford (R).
On January 27, 1967 Tom Stafford, John Young and Cernan were in an altitude chamber “trying to bring a new, untried, stubborn spacecraft up to launch standards”. Meanwhile, in an identical craft, Apollo 1 astronauts veteran Gus Grissom, first American spacewalker Ed White and Cernan’s closest friend the rookie Roger Chaffee, were conducting similar tests atop a Saturn rocket at Cape Kennedy. Minutes later they were dead, killed in a fire – a tragedy stunning the close-knit space community.
In May 1969, Cernan, as part of the Apollo 10 crew along with Tom Stafford and John Young achieved a number of records and a “dry-run” for the Apollo 11 landing two months later. As befitting a crew of test pilots they set the record for the highest speed attained by a manned vehicle at 39,897 km/h during the return from the Moon on May 26, 1969 and hold the record of being the humans who have traveled to the farthest point away from home, some 408,950 kilometres. Cernan and Stafford came within 15.6km of the lunar surface in their lunar module Snoopy.
Jack Schmitt being suited up for dress rehearsal prior to launch. Photo credit NASA.
Harrison “Jack” Schmitt is a geologist and one of the NASA group 4 astronauts, “the scientists“, that were announced on June 28, 1965. His and their story is worthy of is own post, coming in January 2013.
Ron Evans having a suit fitting during the pre-launch phase. Photo credit NASA.
Ron Evans was picked as a Command Module specialist from the beginning of his NASA career. Chosen in April 1966, one of the group 5 astronauts, he was support crew for Apollo 1 and back-up command module pilot for Apollo 14. I found him notable for his almost invisibility in memoirs of the time. In both Deke Slayton’s and Eugene Cernan’s fascinating autobiographies Ron Evans is there an accepted, uncontroversial part of the missions, without a strong personality, extremely competent – obviously the perfect man for the pilot seat of the command module America.
Adventures in the Taurus-Littrow valley
A moon landing was the payoff for all the hard-work, according to Cernan, “the ultimate dream for any pilot.” Following the tradition began by Neil Armstrong on Apollo 11, Cernan, as Commander, was first out on the moon. As he skipped around Schmitt quipped, “Hey, whose been tracking up my lunar surface?” and then stepped out onto a geologist’s paradise – the moon.
The primary objectives for Apollo 17 were: to sample lunar highland material older than the impact that formed Mare Imbrium and investigate the possibility of relatively young volcanic activity in the same vicinity. The Taurus-Littrow valley was selected with the prospects of finding highland material in the valley’s north and south walls and the possibility that several craters in the valley surrounded by dark material could be linked to volcanic activity
Cernan and Schmitt had a three-day lunar surface stay, conducting three periods of extra-vehicular activity, either moonwalking or driving around in the third Lunar Roving Vehicle. They amassed over 22 hours on the surface during these periods in which they collected lunar samples and deployed scientific instruments.
Eugene Cernan on the first EVA, suits still pristine and the Earth above his head. Evocative shot by Jack Schmitt. Photo credit NASA.
The largest haul of lunar rocks was collected by the two moon-walkers as well as deploying the Apollo lunar surface experiments package (ALSEP), a feature of all manned lunar missions. The stations ran from deployment until they were turned off on 30 September 1977 due to: budgetary considerations, the power packs could not run both the transmitter and any other instrument, and the ALSEP control room was needed for the attempt to reactivate Skylab.
They also carried out gravimeter experiments to learn about the moon’s internal structure. The gravimeter was used to obtain readings at the landing site in the immediate vicinity of the lunar module, as well as various locations on the mission’s roving routes.
Eugene Cernan next to the lunar rover vehicle. Photo credit NASA.
Meanwhile the command module also housed a series of scientific experiments. A special bay housed three experiments (as well as cameras and altimeter) for use in lunar orbit: a lunar sounder, an infrared scanning radiometer, and a far-ultraviolet spectrometer. The film canisters were recovered by Ron Evans in a spacewalk after docking with the returned lunar module.
Ron Evans on his space-walk to retrieve film canisters from the outside of the service module prior to separation of the command module and return to earth. Photo credit NASA.
Splashdown in the Pacific on December 19, 1972 brought this “first phase” of human space exploration to a close – I now wait for the second phase to begin and wonder who might it be?
Angela Saini, in her book Geek Nation: how Indian science is taking over the world, wants to convince us that Indian science is taking over the world. Now any well read student of the physical and mathematical sciences will be able to provide you with notable scientific contributions. Even the Indian constitution abjures: “It shall be the duty of every citizen of India to develop the scientific temper”. Does “Indian science” exist, and if so what makes it special?
First, pause and contemplate the following statistics. India is the world’s largest democracy: with a population over 1.23 billion (more than 1 in 6 of the world’s 7.14 billion total population are Indian). India has 415 living languages, with 22 having more that 1 million native speakers – 41% of the population speak Standard Hindi – India’s official language. Some states have their own language as the sole language; Maharashtra (capital Mumbai) has 72 million native Marathi speakers. There are 28 Indian states, the smallest Arunachal Pradesh has 1.3 million people, while the largest, the Hindi speaking Uttar Pradesh, has 199.6 million people, and includes the growing cities of of Lucknow and Kanpur. India is also birthplace to four of the world’s major religions, of which Hinduism has 80.5% of the Indian population as followers. India has a large Muslim following at 13.4% of its population, the third largest Muslim population in the world. Despite so many languages the 2010 adult literacy is 63%, with 8% internet users and a staggering 61 mobile phones per 100 of population. With an improved 88% having satisfactory water facilities only 31% of the population has satisfactory sanitation facilities.
These statistics underlie what a competent revelation Saini’s book is. The diversity of topics is to be applauded. Saini has a breezy, almost whimsical style in introducing topics and providing Indian settings for an perspective of each topic.
In particular I liked her mature handling of two hot-button topics: nuclear power and genetically modified foods. To many in the developed world energy and food security are lifestyle discussions – in India they are of life-and-death importance for many millions of the population, both now and the future.
Saini manages a well-reasoned discussion of the energy option for India – looking in detail at one important option. A visit to the Bhabha Atomic Research Centre provides a first hand glimpse of India’s nuclear aspirations, and reasoning behind it. The ensuing discussion on the indigenous development of thorium based nuclear technologies was both fascinating and compelling. From an economic point of view this development would seem to be a necessity if India is to manage its growth and not burn coal and become a major polluter such as the USA or China. They see this as a crucial intermediate step to a solar energy future. My caution is that India is yet to sign either nuclear ratification or nuclear weapons non-proliferation treaties, a point the author fails to mention.
Similarly a trip around the markets provides a great introduction into genetically modifies crops. India is by both legislation and custom a country of small rural-family run farms. These rural communities are poor and very much at the mercy of the elements. Saini presents a reasoned and sensitive discussion on the development of genetically modified crops (such as a long-life banana) that are relevant to ordinary Indians. There is a greater acceptance of these crops amongst the rural farmers than you first might imagine – provided they are cheap and preferably developed in India.
In addition Saini provides a fascinating look at the development of tuberculosis drugs, the use of electronic documents to speed up the notoriously slow bureaucratic and legal systems of India, as well as electronics and information systems companies. We are taken to the Vikram Sarabhai Space Centre to get a first-hand update on the Indian space program and aspirations. Saini comments, “There’s something unimaginably ambitious about the speed and scale of India’s space programme, as if it’s no longer content fulfilling its early goals of sending up satellites so ordinary people could have colour television and cheaper mobile phone connections. Now it seems India has something else to prove.” With a successful first moon-shot India has established itself as a space power – only lacking a manned mission.
In amongst all of this excellent investigation and examination there was one discordant section. “The mindreading machine” discusses a the use of an Indian lie-detector test based on brain wave measurements. The test has been used as legal evidence in cases, including one of murder, in Indian courts. Saini voices disquiet at this ‘science’ yet at no stage does she state the obvious – that this is not science. There are no theories supporting its claims, no peer review nor double-blind tests to give any credence to the claims. I expect that a science writer would point this out, explicitly; Saini doesn’t.
Including this item in the book highlights a very fascinating aspect of what Saini sees as quintessential Indian science. Indian science nurtures the nutty, allowing questions to be asked and curiosity to be followed before they are shouted down by a conservative mainstream view of what is appropriate science. Interesting scientific and technological achievements aside this for me, is the book’s the defining point – India is having an impact far beyond the scientific statistics and measures. Saini’s book is a welcome and worthwhile look at the the idiosyncrasies and successes of the scientific and technological side of India. I’m not convinced it will take over the world, it will certainly influence and impact the direction of science and technology – that will be interesting to participate in.
Although the question of extraterrestrial life is very old, the concept of full-blown cosmic evolution – the connected evolution of planets, stars galaxies and life on Earth and beyond – is much younger. In a rather breathtaking paper, Steven Dick formerly of the Aerospace History at the National Air & Space Museum places his arguments for cosmic evolution. Dick traces the idea from its roots in the 19th century theories of Pierre-Simon Laplace and Robert Chambers through its philosophical, astronomical, and biological upbringing to the present day. He examines evolution, the worldview that it had become in the 1950s and 1960s and how it had permeated culture in numerous ways and different cultures in diverse ways. Dick cautions us though noting “we need to remember that ‘culture’ is not monolithic and that ‘impact’ is a notoriously vague term.”
In addition to the impact of our new understanding on culture, cosmic evolution also provides a window on long-term human destiny, asserts Dick. He presents this idea via three scenarios, the: the physical , biological, and postbiological universe. Life is unique to earth in the physical universe scenario, and the options flow from this situation – think of Isaac Asimov’s Foundation series. We will certainly interact with extraterrestrials in the biological universe – here cosmic evolution commonly ends in life, mind and intelligence. Cultural evolution in a biological universe may replace biologicals with artificial intelligence creating what Dick calls a postbiological universe. We do not know yet, which of these is our reality, that is one of the challenges of astrobiology, maintains Dick.
In a second ‘big-picture’ paper Marcelo Gleiser presents his four ages of astrobiology. For Gleiser the influx of astrophysical data, particularly on the prevalence of exoplanets “indicates that there are plenty of potentially life-bearing platforms within our galaxy.” He then presents the ‘history’ of life in the universe in terms of the steps needed for matter to have sequentially self-organised into more and more complex structures. His sequence is best viewed as a prelude to the physical or biological universe scenarios of Dick. Gleiser’s fourth age, the Cognitive Age (the age of thinking biomolecules), really addresses whether we are unique or not i.e. which of Dick’s two scenarios, the physical or biological are reality. Gleiser’s first three ages: physical, the creation of stars and planets from atomic nuclei; chemical, in which elements organise into biomolecules; and thirdly biological, in which living creatures of growing complexity form from biomolecules. the papers by Dick and Gleiser are both papers heady and exhilarating conceptual reads.
Jorge Horvath and Douglas Galante accept the premiss that life exists, and then argue we need to take high-energy astrophysical events seriously. Scientists and the public account for meteor impacts in both academic studies, science-fiction writing and film – not so for events such as supernovae, gamma-ray bursts and flares. They show that these events are more frequent than asteroid strikes and that the effects are non-negligible (academic speak for potentially fatal to planet based species). They conclude that just because we have not yet been wiped out by such events can be seen as either a measure of earthlife’s resilience or a threat we are statistically yet to encounter.
My attention was captured by two other papers from the proceedings. Martin Brasier and David Wacey address the problem of studying life in deep space – comparing it to study of life remote in time. This view is pertinent, as it is non-trivial for scientists to determine what is a viable signal of extinct life. The authors develop a set of protocols and then apply these to earth samples, of varying ages. They do this to show how we could interpret similar samples, where much of the desirable information (the context) has been filtered out during the process of transmission (either physical or data) across vast distances of space, or time or both (as is likely on Mars). Even 10 years ago these questions were moot, but we have learned much over the recent past about metabolic pathways and living microbial systems. Brasier and Wacey conclude that there is still work required on pseudo-fossils, structures that arise naturally within complex physico-chemical systems, so that we can confidently agree on signs of life that are remote in space and time.
The Dry Valleys in Antarctica. Photo credit: NASA
My final pick is an experimental paper that looks at the ExoMars mission. The European Space Agency and (initially NASA ) ExoMars mission is scheduled for launch in 2018 – specifically to detect life signatures on the surface and subsurface of Mars. This probe will carry, for the first time, a Raman spectrometer, a technique with proven ability to determine the spectral signals of key biochemicals. The authors support these assertions by assessing samples acquired from Arctic and Antarctic cold deserts and a meteorite crater. These terrestrial environments are similar to those found on Mars. The experimental results presented in this paper demonstrate that it will be possible using this technique to assess and detect spectral signals of extra-terrestrial (Mars in this case) extremophilic life signatures.
The Soviet Union launched Sputnik 1 into an elliptical low Earth orbit on October 4, 1957. This surprise precipitated the space age and triggered the space race. The success ushered in new technological, political, military, and scientific developments.
On April 12, 1961, Yuri Gagarin became the first person in history to leave the Earth’s atmosphere and venture into space. His flight aboard a Soviet Vostok rocket lasted 108 minutes, at the end of it he had ignited the manned space race.
Who were men who responded to these Soviet firsts, launching America into space and then onto the moon?
NASA selected the first US astronauts, the Original Seven (also referred to as the Mercury Seven and Astronaut Group 1), on April 9, 1959. This was the only astronaut group with members who flew on all classes of NASA manned orbital spacecraft of the 20th century — Mercury, Gemini, Apollo, and the Space Shuttle.
The Mercury Seven stand in front of a F-106 Delta Dart. Photo credit NASA.
The first American launched into space was Alan Shepard, followed by Gus Grissom. Their ballistic flights were followed by orbital flights by John Glenn then Scott Carpenter, each managing three orbits. Wally Schirra made six orbits and Gordon Cooper completed the Mercury project with 22 orbits. Cooper was the first American travelling in space for over a day and the last American to be launched solo into Earth orbit. Deke Slayton, was grounded in 1962 due to a heart arrhythmia, but reinstated in 1972 and flew on the Apollo-Soyuz Test Project in 1975.
The New Nine. Back row: See, McDivitt, Lovell, White, & Stafford. Front row: Conrad, Borman, Armstrong, & Young. Photo credit NASA.
With the announcement of the Gemini program and planning of the Apollo program a second group of astronauts were selected by NASA and announced on September 17, 1962. The New Nine augmented the original Mercury 7. While the original seven had been selected to accomplish the simpler task of orbital flight, the new challenges of rendezvous and lunar landing led to the selection of candidates with advanced engineering degrees (for four of the New Nine) as well as test pilot experience.
The Fourteen (seated, left to right) Aldrin, Anders, Bassett, Bean, Cernan, and Chaffee. Standing (left to right) are Collins, Cunninham, Eisele, Freeman, Gordon, Schweickart, Scott and Williams. Photo credit NASA.
Group 3 was the first group to include candidates with no test pilot background. They are the only ones of the first 19 NASA astronaut groups to have no members at all fly on the Space Shuttle.
The fourth group of astronauts, the Scientists, selected by NASA in June 1965, came as a rude shock to the existing astronauts. While the astronauts of the previous three groups were required to have college and some advanced degrees, they were chosen for their test pilot expertise. The six members of this group, on the other hand, were chosen for their research and academic backgrounds. Doctorate degrees were required and minimum flight time requirements were waived for this group.
Scientist-Astronauts: Front row, L-R: Michel, Schmitt, and Kerwin. Back row, L-R: Garriot, and Gibson. Photo credit NASA.
John Young labelled the next astronaut group, selected by NASA in April 1966, the “Original Nineteen” in parody of the original seven Mercury astronauts. Of the six Lunar Module Pilots that walked on the Moon, three came from this group (Charles M Duke Jr, James B Irwin, and Edward D Mitchell). This group is also distinctive in being the only time when NASA hired a person into the astronaut corps who had already earned astronaut wings, X-15 pilot Joseph “Joe” H Engle.
The final group of this era, the second group of scientist-astronauts, were appointed by NASA on August 11, 1967. They were labelled the “excess Eleven” with only five, including the first Australian born astronaut Philip Chapman, given formal assignments in the Apollo Program, and these were all non-flying. These were: Joseph P Allen, Chapman, Anthony W England, Karl G Henize, and Robert A R Parker. Chapman resigned from NASA in July 1972 due to lack of space-flight opportunities. Three others, Donald L Holmquest, Anthony A Llewellyn, and Brian T O’Leary resigned earlier from the group for various reasons.
The Excess Eleven civilian scientists. Seated at the table, L to R: Chapman, Parker, Thornton, and Llewellyn. Standing, L to R: Allen, Henize, England, Holmquest, Musgrave, Lenoir, and O'Leary. Photo credit NASA.
Assignments for the group were delayed by the requirement to spend a full year to become qualified as jet pilots (as were the Group 4 scientists before them). This requirement for scientists to be trained as jet pilots was eventually lifted with the creation of the Mission Specialist position in the Shuttle Program. The seven members (Allan, England, Henize, William “Bill” Lenoir, Story Musgrave, Parker, and William E Thornton) of Group 6 who stayed with the program after Apollo went on to form the core of Shuttle Mission Specialists, accomplishing a total of 15 flights.
This chart organizes each NASA astronaut group by order of their assignment to fly. Codes as explained in the legend illustrate each person's skills and accomplishments. Image credit: Tdadamemd
In all 66 men became NASA astronauts during this first era of manned space exploration. No women were included – although there was an unofficial group called the First Lady Astronaut Trainees– not being jet test pilots there were ineligible to become astronauts.
Was this a “boys’ own adventure”? Was this a period of great social upheaval in the USA? Did this era cement in the US politicians and public the image of supremacy and isolationism in space endeavors? Yes, is the answer to all three questions.
There are a myriad of stories from these groups’ exploits. These stories have a contemporary relevance as we reach an era of: new commercial space opportunities (leisure, exploration and mining), new entrants (China and India), and find the US and Europe hampered by self-imposed budget challenges and hurdles.
Pioneer 10 and 11unveiled the solar system during the golden-age of robotic exploration. Their missions were a success; Pioneer 10 threading the asteroid belt to provide our first close view of Jupiter and its moons, Pioneer 11 catapulting past Jupiter and foraying through the plane of Saturn’s rings.
Saturn and its moon Titan imaged by Pioneer 11 in 1979. Photo credit NASA/JPL.
The Pioneers, true to their name, kept travelling – out of the solar system – into space legend. We lost communication with Pioneer 11 in 1995, and with Pioneer 10 in 2003 when it had reached a distance 80 times further than the Earth from the Sun. Some years prior to this, when the probes had traveled only one quarter of this distance, scientists realized both were thousands of kilometres closer to the Sun than expected.
Space exploration depends on precise measurements of every factor involved in the mission – particularly distance. Beams of radio waves were sent and bounced off the Pioneer spacecraft to measure the probes’ movement. The distance to the spacecraft and its speed were calculated from the photons’ round trip time and their Doppler shift (the frequency change you hear as an ambulance siren approaches and then recedes from you).
Gas leakage, measurement error or other mundane reasons might explain the Pioneer anomaly. Heat, unevenly radiating off the probes, slowing their voyage, is proposed by Jet Propulsion Lab scientists, in a new Physical Review Letters article, to account for the anomaly. After constructing a finite-element thermal model of the two spacecraft, the authors modeled the effects of thermal recoil forces on Pioneer 10 at various distances from the Sun.
Finite element analysis of thermal radiation from Pioneer 10. Image credit JPL.
A second paper in a sister journal, Physical Review D, proposes a totally different cause and conclusion. Flat (neither expanding nor contracting) background spacetime with a solar system gravitationally isolated from the rest of the Universe is the cornerstone of current theory. The new study extends this theoretical concept, formalizing the description of particles and photons moving in the gravitational field of a localized astronomical system now embedded in an expanding universe.
The proposed changes to the astrophysics theory are mathematically complex, the paper is densely populated with “post-Newtonian cosmological field equations” – the conclusions though are emphatically clear. Terms, proportional to the local expansion of the universe, are missing from the equations of light propagation currently used by space navigation centres for fitting distance and speed observations of satellites and celestial bodies. With this correction the Pioneer anomaly disappears; the photons were moving faster than expected from the theory, the spacecraft were actually travelling the correct speed.
NASA New Horizons space probe. Image credit NASA/JPL.
So which of these two competing papers explains the Pioneer anomaly? Which will solve this nagging problem and be of benefit to future interstellar travel? We may need to wait beyond 2015 to find an answer. With no new Pioneer data, proof will rely on measurement from NASA’s New Horizons mission, launched in 2006 and set to reach Pluto in 2015.
Science this month tackled many of the big questions: Where did life on Earth originate? How do we learn? How can we live healthy lives? and, What is it with scientists and sticky-tape?
Lithopanspermia is the idea that basic life forms are distributed throughout the universe via meteorite-like planetary fragments. Eventually, another planetary system’s gravity traps these roaming rocks, which can result in a transfer of any living cargo.
Researchers reported that under certain conditions there is a high probability that life came to Earth — or spread from Earth to other planets — during the solar system’s infancy when Earth and its planetary neighbors orbiting other stars would have been close enough to each other to exchange lots of solid material.
Image Credit: Shutterstock
Previous research suggests that the speed with which solid matter hurtles through the cosmos makes the chances of being snagged by another object highly unlikely. This research reconsidered lithopanspermia under a low-velocity process called weak transfer in which solid materials meander out of the orbit of one large object and happen into the orbit of another. In this case, the researchers factored in velocities 50 times slower than previous estimates, or about 100 meters per second.
Using the star cluster in which our sun was born as a model, the team conducted simulations showing that at these lower speeds the transfer of solid material from one star’s planetary system to another could have been far more likely than previously thought.
The researchers suggest that ideal conditions for lithopanspermia in the sun's birth cluster, in the solar system and on Earth overlapped for several hundred million years (blue shaded area). Rock evidence suggests that the Earth (bottom line) contained surface water during a period when the relative velocities between the sun and its closest cluster neighbors (top line) were small enough to allow weak transfer to other planetary systems, and when the solar system (middle line) experienced high meteorite activity within the sun's weak gravitational boundary. If life arose on Earth shortly after surface water was available, life could have journeyed from Earth to another habitable world during this time, or vice versa if life had an early start in another planetary system. Image credit: Amaya Moro-Martín
The researchers suggest that of all the boulders cast off from our solar system and its closest neighbor, five to 12 out of 10,000 could have been captured by the other. Earlier simulations had suggested chances as slim as one in a million.
This research highlights that life could have originated away from earth. The theory that it did is yet to be demonstrated.
Research has again shown that you can indeed “teach old dogs new tricks.” The brain you have at any stage of your life is not necessarily the brain you are always going to have. It can still change, even for the better. This time however the researchers observed changes in the brain’s white matter.
Most people equate “gray matter” with the brain and its higher functions, such as sensation and perception, but this is only one part of the anatomical puzzle inside our heads. Another cerebral component is the white matter, which makes up about half the brain by volume and serves as the communications network.
The gray matter, with its densely packed nerve cell bodies, does the thinking, the computing, the decision-making. Projecting from these cell bodies are the axons – the network cables. They constitute the white matter. Its color derives from myelin – a fat that wraps around the axons, acting like insulation.
Human brain right dissected lateral view, showing grey matter (the darker outer parts), and white matter (the inner and prominently whiter parts). Photo credit: John A Beal, Dep't. of Cellular Biology & Anatomy, Louisiana State University
This study looked at a really complex, long-term learning process over time, actually looking at changes in individuals as they learn a language. The work demonstrates that significant changes in the mylenation were observed in adults as they were learning. This research demonstrates how learning is a many step process in our brain.
The flip-side of learning is the persistence of misinformation. Why does that kind of ‘learning’ stick? A new report explores this phenomenon. According to the researchers rejecting information actually requires cognitive effort. Weighing the plausibility and the source of a message is cognitively more difficult than simply accepting that the message is true. If the topic isn’t very important to you or you have other things on your mind, misinformation is more likely to take hold.
Misinformation is especially sticky when it conforms to our preexisting political, religious, or social point of view. Because of this, ideology and personal worldviews can be especially difficult obstacles to overcome.
Even worse, efforts to retract misinformation often backfire, paradoxically amplifying the effect of the erroneous belief.
Though misinformation may be difficult to correct, all is not lost. According to the report, these strategies can set the record straight.
Provide people with a narrative that replaces the gap left by false information
Focus on the facts you want to highlight, rather than the myths
Make sure that the information you want people to take away is simple and brief
Consider your audience and the beliefs they are likely to hold
August was a momentous month for science and technology. In my top five events are: NASA landed a car-sized rover on Mars; the first man to walk on the Moon, Neil Armstrong dies; Harvard scientist create a cyborg tissue; Swedish researchers detail how Parkinson’s disease spreads through the brain; and Voyager 2 turns 35.
Without a doubt the technology achievement of the month goes to NASA. They landed the rover, Curiosity, successfully on Mars at 1:31 a.m. EDT August 6, 2012. Ending a 36-week flight and beginning a two-year investigation. What makes this noteworthy? For one the coverage and access NASA provided in real time. From the launch to the daily updates to the ‘on the spot’ coverage of the entrance-descent-landing sequence live from the Pasadena control-room. Showing that engineers and scientists are human after all.
I was delighted to see the sky-crane landing working to perfection. As the system were all bought to life one-by-one the science exploration staff are eagerly anticipating zapping, sampling and analysing rocks, regolith and atmosphere.
Curiosity parachuting to the Martian surface. Photo credit NASA/JPL.
“Today, the wheels of Curiosity have begun to blaze the trail for human footprints on Mars. Curiosity, the most sophisticated rover ever built, is now on the surface of the Red Planet, where it will seek to answer age-old questions about whether life ever existed on Mars, or if the planet can sustain life in the future,” said NASA Administrator Charles Bolden. “This is an amazing achievement, made possible by a team of scientists and engineers from around the world and led by the extraordinary men and women of NASA and our Jet Propulsion Laboratory. President Obama has laid out a bold vision for sending humans to Mars in the mid-2030’s, and today’s landing marks a significant step toward achieving this goal.”
The bold vision for sending humans to Mars was poignant. Neil Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died, following complications resulting from cardiovascular procedures. He was 82. Without a doubt Neil Armstrong, Buzz Aldrin and Michael Collins were childhood heroes to me. They along with the other astronauts of both the Apollo and Gemini missions were a key inspiration in firstly my interest in and secondly my career in science.
The only picture taken of Neil Armstrong on the Moon. Neil was carrying the camera (seen in his hands here) during the entire moon-walk so all images captures Buzz Aldrin. This image was captured by a stationary camera on the Lunar landing module. Image credit NASA.
“Houston, Tranquillity Base here. The Eagle has landed,” Armstrong said, telling a tense and waiting Earth that men had finally reached the lunar surface. Neil Armstrong was also a reluctant American hero who always believed he was just doing his job. A refreshing change from the current days of hyped useless celebrities and where the word awesome is applies to every mundane activity. Traveling to the Moon, that inspires a sense of awe.
Meanwhileresearchers at Harvard have grown cyborg tissues with embedded nanoelectronics. They have reported how they developed a system for creating nanoscale “scaffolds” which could be seeded with cells which later grow into tissue.
Though a number of potential applications exist for the technology, the most near-term use may come from the pharmaceutical industry. Researchers could use it to more precisely study how newly developed drugs act in three-dimensional tissues, rather than thin layers of cultured cells. The system might also one day be used to monitor changes inside the body and react accordingly, whether through electrical stimulation or the release of a drug.
Parkinson’s researchers at Lund University for the first time were able to follow events in which misfolded proteins travel from sick to healthy cells. This model has never before been identified so clearly in a living organism. The experiments also show how the transferred proteins attract proteins in the host cell leading to abnormal folding or “clumping” inside the cells. This is a cellular process likely to lead to the disease process as Parkinson’s progresses, and it spreads to an increasing number of brain regions as the patient gets sicker.
The aim of the research is to better understand how Parkinson’s pathology progresses and thereby uncover novel molecular targets for disease-modifying treatments.
Voyager 1. Image credit NASA/JPL
Finally what an inspiring longevity story. Thirty-five years ago, NASA’s Voyager 2 spacecraft, the first Voyager spacecraft to launch, departed on a journey that would make it the only spacecraft to visit Uranus and Neptune and the longest-operating NASA spacecraft ever. Voyager 2 and its twin, Voyager 1, that launched 16 days later on Sept. 5, 1977, are still going strong, hurtling away from our sun. Mission managers are eagerly anticipating the day when they break on through to the other side – the space between stars.
I trust you have enjoyed my idiosyncratic “five best new science and technology” stories of this past calender month. These were in most cases, but not exclusively so, announced through peer reviewed journals. These were those that I found most interesting, or influential, or of possible future impact. No science applied to my choice, the choice was my responsibility alone!
An international group of researchers announced in the journal Nature that they had succeeded in creating tin-100. This experiment helps us understand how heavy elements have formed. A few minutes after the Big Bang the universe contained no other elements than the lightest; hydrogen and helium.
We, the objects around us, the Earth and the other planets all contain heavier elements; carbon, oxygen, silicon, tin, iron etc. These elements came into existence later than hydrogen and helium. They formed through the fusion of atomic nuclei inside of stars. Elements heavier than iron owe their existence to gigantic stellar explosions called supernovas. Tin-100 is a very unstable, yet important, element for the understanding the formation of these heavier elements.
The inspiration of creating new elements can be traced to alchemical traditions. Alchemy is an arcane tradition, that can be viewed as a proto-science, a precursor to chemistry and nuclear physics. It’s prime objective was to produce the mythical philosopher’s stone, which was said to be capable of turning base metals into gold or silver, and also act as an elixir of life that would confer youth and immortality upon its user.
The Alchemist, 1771 painting by Joseph Wright of Derby. Image credit: Wikipedia, image copyright has expired.
It did bring to chemistry many ideas and provided procedures, equipment, and terminology that are still in use. It also provided the inspiration for the creation of new elements. Now we understand to create new elements requires a combination of precision equipment and experimental procedures coupled with a sound understanding of quantum theory.
So what is tin-100 and why is it useful to understand the astrophysics of heavy element formation?
Most people will recognise that matter around us is composed of atoms. Atoms of carbon, hydrogen, oxygen for example form the building blocks to make organic molecules and silicon and oxygen bond together to make common beach sand and are fused together to make glass. The familiar metals are solids made of one type of atom, for example gold and aluminium, or combinations, bronze being made of copper and tin atoms.
Atoms in turn are a central nucleus of protons and neutrons surrounded by a swarm of electrons. The number of protons distinguishes one element from another. This atomic number is used to designate an element 1 for hydrogen, 8 for oxygen and 50 for tin, for example. Stable tin comprises 112 nuclear particles – 50 protons and 62 neutrons. The neutrons act as a kind of buffer between the electrically repelling protons and prevent normal tin from decaying. Each atom will contain an equal number of electrons to its protons. Remove or add an electron and the atom becomes an ion, a charged particle.
The strange quantum world of the nuclei
Quantum mechanics which, amongst other things, explains how the electrons form into shells around the nucleus. Elements which have filled outer shells, helium, neon, argon, xenon are ‘noble’ gases, chemically inert – not the least reactive. Nuclei are also complex quantum objects.
As far as we know, nuclei are the smallest objects that can be split up into their constituents. They are therefore the smallest entities which emergent properties – patterns that arise from complexity – can be studied. Nuclear scientists study these emergent phenomena and are using them to decipher the nature of the nuclear force. In contrast to the structure of atoms, for which the fundamental interaction between the electrons and the nucleus – the electromagnetic force – is known with great precision, the interaction between the nucleons – the strong nuclear force – is not so well known.
In nature not all combinations of nucleons are stable. As a general rule the more protons present then more neutrons are required to stablise the nuclei. A useful graphical presentation of this is the Segre table of radionuclides.
Location of nuclei as a function of their neutron number (N) and proton number (Z). Image credit Daniel Bazin Michigan State University.
If the shell structure of electrons was difficult at first for scientists to come to terms with, then the shell structure exhibited by nucleons is not only unexpected it is complex enough not to be discussed in many quantum physics texts. It was first thought that such densely packed and strongly interacting objects as the nucleons would exhibit a liquid-like behavior, much like the flow of electrons in a good conductor such as a metal.
That is what makes these experiments so exciting.
Stability and magic numbers
Magic numbers are the number of protons or neutrons that form full shells in an atomic nucleus. The term is thought to have been coined by the physicist Eugene Wigner. The model has been used to explain – at least for stable nuclei – the observed sequence of magic numbers: 2, 8, 28, 50, 82 and 126.
Nuclei that have a magic number of neutrons or protons are more tightly bound than there non-magic counterparts. This intrinsic simplicity makes them prime candidates for testing proposed models of nuclear structure. Even more attractive are the doubly magic nuclei. The lighter nuclei helium-4, oxygen-16 and calcium-40 do follow the magic number sequence.
However because of the repulsion between protons the line of stable nuclei veers away from the symmetry line. As a result tin-100 represents the largest nuclei to follow the sequence. It is bound but unstable. It is very close to the edge of nuclear stability, where the nuclear force between the protons and neutrons can no longer bind them into a nucleus. Unfortunately, what makes this nucleus so attractive to study is what also makes it so difficult.
How to make a new element
In nature elements heavier than iron come into being only in powerful stellar explosions – supernovas. These include, for example, the precious metals gold and silver and the radioactive uranium. The cauldron of a supernova gives rise to a whole array of high-mass atomic nuclei. these decay to stable elements via different short-lived intermediate stages.
There are two ways to create new elements in the laboratory. The first is is to fuse two nuclei in a manner that minimises the loss of protons or α-particles (helium-4 nuclei). The second is is more brutal, fragmenting a small part off a heavier nuclei in a collision.
The detector set-up at GSI. Photo credit: GSI
In these experiments energetic xenon-124 is sheared by making it collide with a target beryllium foil leaving a residue that is composed of 50 neutrons and 50 protons. Out of the 120,000,000,000,000 xenon-124 accelerated in the experiment, only 259 tin-100 nuclei were identified. These results were sufficient though for the decay of tin-100 to be studied with great precision.
The results, excitedly for the researchers, demonstrated a ‘superallowed Gamow-Teller decay‘. This type of β-decay is beyond the scope of this essay to explain, needless to say it does provide new experimental depth to the models of nuclear chemistry. It is an important decay transition that occurs in the collapse of supernovae. It also is important in putting boundaries on the possible mass of the neutrino. Both of which are important validations of the current nuclear theories as well as providing real experimental data to fine tune the theoretical models.
This allows more real models of nuclear synthesis to be constructed. Allowing a deeper understanding of how the atoms that make up our universe were created.
Now other laboratories around the world will work on improving the production rates of tin-100 and other exotic nuclei, based on these experiments. Allowing the emergent properties of these nuclei can be studied in more detail. Giving us greater understanding of the forces that bind these particles together – to make us!
NASA’s rover Curiosity was safely on Mars. It was a perfect landing. The novel sky-crane method had proved its detractors wrong and its designers right. What was needed then was signs that Curiosity was working as designed. NASA had said that the first pictures may be anything up to 2 hours after landing. A long time for the audiences, waiting, live, all over Earth.
It's a wheel on Mars. Photo credit NASA/JPL
“Got thumbnails.” Pause in the control centre, then someone else yells “Its a wheel, its a wheel!” “A wheel on Mars!” For the second time that momentous afternoon the NASA/Jet propulsion Lab crowd erupted into spontaneous and joyful applause. Not only had they landed the rover, Curiosity, safely on Mars, they had received the first images back from its cameras. Sometimes the unscripted, unexpurgated exclamations make for the best history.
The first two pictures were from the front and back navigation cameras. They were low resolution black and white thumbnails taken through the dust caps that protected the cameras during landing. As the minutes ticked by higher resolution images came through from the rover. The business as usual, familiar image enhancement bought into sharp clarity the ‘first’ two images from the robot explorer.
The 'first' image enhanced view from the rear hazard camera, Mars Curiosity Sol 0.
The first week on Mars
After the exuberance and press conference came the trademark NASA precision and methodical approach. An approach that gets missions safely to Mars, at the same time can make the audacious appear mundane.
Mission controllers at NASA’s Jet Propulsion Laboratory in Pasadena, are now checking out Curiosity’s subsystems and 10 instruments. Curiosity is in the opening days of a two-year mission to investigate whether conditions have been favorable for microbial life and preserving clues in the rocks about possible past life.
Mission team members are “living” on Mars time. A Martian day is approximately 40 minutes longer than an Earth day, meaning team members start their shift 40 minutes later each day.
View of Mount Sharp, Curiosity's roving destination. Image credit NASA/JPL
Amongst the important system events in this first week was a software upgrade. It took four days to successfully upgrade Curiosity’s software in its main and back-up computer. The software had been uploaded during its trek to Mars, but not activated until now. The software to date was focused on getting Curiosity through the Martian atmosphere and safely to its destination in Gale Crater. The software upgrade is to cover its surface exploration activity, roving and controlling the various scientific instruments.
Curiosity Ready to Roll
“There will be a lot of important firsts that will be taking place for Curiosity over the next few weeks, but the first motion of its wheels, the first time our roving laboratory on Mars does some actual roving, that will be something special,” said Michael Watkins, mission manager for Curiosity from the Jet Propulsion Laboratory.
Mission engineers are devoting more time to planning the first rove of Curiosity. In the coming days, the rover will exercise each of its four steerable (front and back) wheels, turning each of them side-to-side before ending up with each wheel pointing straight ahead. On a later day, the rover will drive forward about one rover-length 3 metres, turn 90 degrees, and then kick into reverse for about 2 metres. Exciting times for the rover driver team!
This image shows the landing site of NASA's Curiosity rover and destinations scientists want to investigate. Photo credit NASA/JPL
The scientists and engineers of NASA’s Curiosity rover mission have selected the first driving destination for Curiosity. The target area, named Glenelg, is a natural intersection of three kinds of terrain. The trek to Glenelg will send the rover 400 metres east-southeast of its landing site. One of the three types of terrain intersecting at Glenelg is layered bedrock, which is attractive as the first drilling target.
The choice described by Curiosity Principal Investigator John Grotzinger of the California Institute of Technology as, “With such a great landing spot in Gale Crater, we literally had every degree of the compass to choose from for our first drive.” “We had a bunch of strong contenders. It is the kind of dilemma planetary scientists dream of, but you can only go one place for the first drilling for a rock sample on Mars. That first drilling will be a huge moment in the history of Mars exploration.”
Grotzinger estimated the rover’s journey would take between three weeks and two months to arrive at Glenelg, where it will stay for roughly a month before heading to the base of Mount Sharp.
It may be a full year before the remote-controlled rover gets to the base of the peak, which is within 20 kilometres of the rover’s landing site.
Zapping rocks and doing science
Before Curiosity heads off to Glenelg another first will occur. The team in charge of Curiosity’s Chemistry and Camera instrument, is planning to give their mast-mounted, rock-zapping laser and telescope combination a thorough checkout. ChemCam has “zapped” its first rock in the name of planetary science. It was the first time such a powerful laser has been used on the surface of another world.
The Chemistry Camera calibration target, as seen by the camera. Photo credit NASA/JPL.
The technique is called ‘laser-induced breakdown spectroscopy’. The high-powered, narrow-focused, laser beam vaporises the rock from a distance generating a plasma plume with temperatures in excess of 100,000°C. At the high temperatures during the early plasma, the vaporised material breaks down into excited ionic and atomic species. As it cools to 5,000–20,000°C the characteristic atomic emission lines of the elements can be recorded by the camera. This data is compared to the ‘standards’ that the rover carries to identify the rock components.
The soon to be famous rock N165, target for testing the Chemistry Camera laser and analysis. Photo credit NASA/JPL.
As Roger Wiens, principal investigator of the ChemCam instrument from the Los Alamos National Laboratory explained earlier, “Rock N165 looks like your typical Mars rock, about three inches wide. It’s about 10 feet away.” “We are going to hit it with 14 millijoules of energy 30 times in 10 seconds. It is not only going to be an excellent test of our system, it should be pretty cool too.”
Pretty cool indeed.
First weather report in 30 years
It is currently just above freezing point in gale Crater where Curiosity is.
Grotzinger noted the team’s report on the Martian crater’s temperature was “really an important benchmark for Mars science”.
“It’s been exactly 30 years since the last long duration monitoring weather station was present on Mars,” when Viking 1 stopped communicating with Earth in 1982,” he said. Then Viking 1 lander recorded temperatures that varied from −17.2 °C to −107 °C.
Sensors on two finger-like mini-booms extending horizontally from the mast of NASA’s Mars rover Curiosity will monitor wind speed, wind direction and air temperature. One also will monitor humidity; the other also will monitor ground temperature. The sensors are part of the Rover Environmental Monitoring Station, provided by Spain for the Mars Science Laboratory mission.
The weather station devices on Curiosity being tested prior to launch. Photo credit NASA/JPL.
In this image, the spacecraft specialist’s hands are just below one of the Rover Environmental Monitoring Station mini-booms. The other mini-boom extends to the left a little farther up the mast.
As Curiosity’s primary mission is for a full Martian year it will be able to record the seasonal variations that occur for Mars.
On the ground radiation monitoring and weather conditions will be crucial for any future exploration or habitation by humans. This mission by Curiosity represents an important step towards these aspirations.
The NASA rover Curiosity is expected to be landing on Mars at 3:31 am August 6, 2012 (AEST). It’s mission, lasting one Martian-year (98 Earth weeks), is of scientific significance and perhaps even of human significance. Curiosity will be fulfilling the prospecting stage of a step-by-step program of exploration, reconnaissance, prospecting and mining evidence for a definitive answer to the question “Has life existed on Mars?
Do you wish to become a Martizen, a citizen of Mars, anytime in the near future? If you are serious about this then Dutchman, Bas Lansdorp is your man.
Bas Lansdorp is a person with an audacious ambition. Through his company, Mars One, he plans to establish the first human settlement on Mars by April 2023. In addition to this he intends that a new team of four settlers will join the Martian settlement every two years. By 2033 there will be over twenty people living, working, and they believe, flourishing on Mars, their new home.
If the Mars one publicity is believable, and on this point there is no real reason to doubt it, organizing a manned mission to Mars has been Bas Lansdorp’s dream for many years. Bas has been working on Mars One with partner Arno Wielders since January 2011. During 2011 they had confidential discussions with possible equipment suppliers to ensure that there was reality in their idea. In May 2012 they announced their vision to the world.
Like any large entrepreneurial venture their success will predicated on the skill, experience and credibility of the venture and the people involved. To be credible they will need to be convincing in, at least, these four aspects of the venture; technological; financial; psychological; and finally ethical. They will need to be convincing in a way that engages and excites both investors and participants.
It is rocket science
Getting to Mars is not trivial, if it were, well I expect there would be more than the spectacular array of NASAsuper, and superannuated rovers there currently is on Mars. Mars One have developed and made integral to their model a simple theme to get to and live on Mars: buy already developed technology from existing component manufacturers.
Take the Falcon Heavy lifter from SpaceX, to boost the components into low earth orbit. Combine a SpaceX Dragon capsule as the landing stage, add a transit living module from Thales Alenia Space and attach to two propellant stages which are a variant of the SpaceX Falcon 9 upper stage rockets and you have the vehicle to get from low earth orbit to orbit around Mars via a Hohmann transfer trajectory.
The seven-month trip to mars will be Spartan, similar to, but more cramped, than current conditions experienced on the International Space Station. This is where rigorous training will first pay off:
“Showering won’t be an option; instead they will have to make do with wet wipes like the International Space Station astronauts. Tinned food only, constant noise from the ventilators and equipment and a regimented routine of three hours of exercise a day to keep up muscle mass all add to their trials. If they are hit by a solar storm they will have to take refuge in the shelter area of the rocket, which provides the best protection, for as long as several days.”
When the first 4 settlers land on Mars in April 2023 they will arrive at an established site. They will be picked up from their SpaceX Dragon capsule and taxied to the settlement by two robotic Mars rovers designed and built by MDA Space Missions. To get to this point is an ambitious and tight timeline.
2013
Settler selection begins. Replica of Mars settlement is built on an Earth desert to help the settlers prepare and train, and for a realistic environment in which to test the equipment. The settler selection and the preparations in the simulated Mars base will be broadcast on television and online for the public to view.
2014
Preparation for the supplies mission. Production of the first Mars communication satellites.
2016
January launch of the supplies mission, landing in October, includes the first habitat module (modified Dragon capsule) and 2500kg of supplies.
2018
First robotic rover lands (again in a modified Dragon capsule) to enable the pick of the specific settlement site.
2021
A total of 2 robot rovers, 2 living units, 2 life support units and 2 supply units are now all present at the Mars settlement site.
2022
All H2O, O2, and atmosphere production will be ready before a go-ahead to launch the settlers.
2023
First 4 settlers arrive at the Mars settlement.
2025
Second group of 4 settlers arrive, to be no doubt enthusiastically greeted by the pioneering first four.
Once arrived there will be work for the settlers to connect up the various habitats. However once complete they will have substantial living space, 50m²+ each, equipped with showers, flushing toilets and kitchens. The living units are a Dragon capsule with an inflatable living section supplied by ILC Dover, who have supplied NASA with space suits and landing bags for the previous Mars rovers Opportunity and Spirit. The inflatable living sections are to be covered in Martian regolith to provide adequate radiation shielding.
Mars One
When moving around on the Mars surface the settlers will be wearing Mars suits, similar to the suits worn by the Apollo astronauts on the Moon. These suits will be made by Paragon Space Developments, the same company who provide NASA with ‘extra-vehicular’ suits, for when astronauts work in space outside the International Space Station.
By focussing on proven existing technologies Mars One are certainly presenting a reliable low cost technology solution. It is also deceptively simple. Let us remind ourselves this is a first, these conditions will be new.
For example the first step to settlement, safely landing the settlers on Mars, is unproven at present. NASA has described the process of entering the Red Planet’s atmosphere and slowing down to land as “six minutes of terror.” Computer graphics of Mars landings, in full colour and exquisite detail do not provide the simple fact that landing payloads that are large enough to bring humans and sustain their survival on the Red Planet is still beyond our capability. Currently NASA expects to have testable solutions to this some time in 2014.
Similarly we could look at the Mars suits and pose, repairs? replacements? These will be an absolute necessity for survival, however you won’t be able to buy a replacement online or wander down to high street shops to get an upgraded model or new one for a growing Martizen child.
Competent and knowledgeable engineers and specialists, as well as countless armchair experts, will no doubt be picking apart the technology of the Mars One mission, as I have just briefly done. There is no doubt that each step of the timetable above has a myriad of ‘first-time’ problems that will require solutions, some of which can be inferred some which will only become apparent as the experience proceeds. I hope that all involved have read Gregory Benson’s 1999 novel, The Martian Race, a gripping primer to life on Mars.
Show me the money
Mars manned mission. Image credit: NASA
Getting to Mars is not cheap. Since the late 1940s there have been many proposals for manned exploration and settlements on mars. A commonality is that they are all pitched 10-20 years in the future and large sums of money are mentioned. To put this into today’s context on August 6 (EDT), 2012 NASA’s Mars rover, Curiosity, will land on Mars. This mission will place an 899kg six-wheeled, un-manned science laboratory on Mars; for the approximate mission cost of US$2.5B. It is expected that a 2030s NASA mission to Mars will be of the order of US$20B. Mars One says it will cost them US$6B to put the first four settlers on Mars.
In many ways focusing on the mission cost is a furphy. NASA mission budgets come from USA public purses and there is always great argument in the US Senate about the value of such publically funded scientific enterprise. In the US this argument is always balanced by the technology and enterprise that this brings to US companies and the economy. Mars One have no such public funding in mind. They intend to buy the above technologies based on price and quality, not through political or national preferences.
Colonisation of Mars 2023, Mars One. Image Credit: Ariukux
The ability to fund such a mission will depend on what value it returns for investors. Here is the Mars One point of difference; funding will be via sponsorship and as the World’s largest media event. If I were a settler having ILC Dover and Paragon Space Development would be more reassuring than IKEA on my Living and Life Support Modules. As for the thought of a 7 months trip to Mars eating McDonalds pre-prepared ‘meals’ that would be unpalatable. Choose the sponsors wisely Mars One.
There are no stated scientific or economic goals. Instead they see it this way:
“A manned mission to Mars is one of the most exciting, inspiring and ambitious adventures that mankind can take on. We see this as a journey that belongs to us all, and it is for this reason that we will make every step one that we take together. This will also be our way to finance the mission: the mission to Mars will be the biggest media event ever! The entire world will be able to watch and help with decisions as the teams of settlers are selected, follow their extensive training and preparation for the mission and of course observe their settling on Mars once arrived. The emigrated astronauts will share their experiences with us as they build their new home, conduct experiments, and explore Mars. The mission itself will provide us with invaluable scientific and social knowledge that will be accessible to everyone, not just an elite select few.”
To assist in making this worldwide media frenzy Mars One has enlisted Paul Römer as an ambassador. An established expert on grasping the attention of a global public, he was the co-creator of the worldwide phenomenon “Big Brother” – the television program that revolutionized reality television.
The 24/7 Martizen lab-rat
More than the tangibles of this venture, I believe it will be the intangible elements that make this a standout human endeavour. Especially the ethics and psychology of the Martizen being media fodder 24/7. A previous article has already questioned the ethics of such, admitedly voluntary, surveillance.
The psychology of such surveillance is fascinating and worrying. Even the most extroverted of people have private lives. Only the totally naive display ‘real’ faces through the public media. Media such as facebook display a mixture unconscious representations, as well as carefully and foolishly contrived facets of our lives. In many cases events are morphed and selectively recorded on media such as facebook and twitter. It is one thing to post to your facebook friends, it is quite a different thing to know that all that you do will be on display for a public you do not know.
It is hopefully obvious that the narcissist, wastrel, celebrity personalities that populated the many versions of Big Brother are not what will make a great four-person team on Mars. I also am happy to be labelled an ‘elitist’ and state that public participation via stringent selection processes, such as voting-off someone you don’t like, will be a disaster for a serious mission.
I am unsure how history’s first off-world conception, birth and death will go as media events. I can appreciate the lure for marketers of such landmark voyeuristic events, I am at the same time unsure how the participants of such private events will feel.
Mars500 crew. Photo credit ESA
There is psychologically a world of difference between the isolation that would be experienced in genuine remote exploration, think Antarctica, to the pseudo-isolation of contrived event that has a definite endpoint, think Big Brother and Survivor. The Marsonauts of Mars500 ended with smiling faces after their 17 month long isolation experiment. The European Space Agency’s Directorate of Human Spaceflight has a long tradition of conducting research on the physiological and psychological aspects of spaceflight. In light of this, ESA undertook the Mars500 cooperative project with the Russian Institute for Biomedical Problems (IBMP) in Moscow, in 2010-11. This all male crew experiment is instructive, and illuminating for Mars One, however no matter how ‘isolated’ Moscow may feel, like the people in the Big Brother household, they could if they chose leave at any stage.
Despite this a key science project during Mars500 was to determine the implications of personal values held by individual crew-members for compatibility within the group as a whole or otherwise, and for individual coping strategies and adaptation during long lasting confinement. On a human exploration mission to Mars, the psychological resilience of the crew will play a critical role for the maintenance of health and performance and hence the success of the mission. One factor impacting on psychological resilience is the personal values of crew members defining their motivational goals and attitudes. Crew member selection is for real, not a game where if a poor choice is made they leave the set or you re-boot the computer.
It’s a one-way trip
That is one clear distinction this is a one-way journey. Since returning astronauts from the surface of Mars is one of the most difficult, and expensive, parts of a Mars mission, the idea of a one-way trip to Mars has been proposed several times. The notion of settlers, rather than expedition astronauts changes the technology and psychology of the mission.
A one-way trip scenario has been proposed seriously a number of times since 1998. Including a 2004 proposal by Paul Davies. Another organisation, Mars to Stay, proposed that astronauts sent to Mars for the first time should stay there indefinitely, both to reduce mission cost and to ensure permanent settlement of Mars. Among many notable Mars to Stay advocates, former Apollo astronaut Buzz Aldrin is a particularly outspoken promoter who has suggested in numerous forums “Forget the Moon, Let’s Head to Mars!”
During a 2009 public hearing of the U.S. Human Space Flight Plans Committee at which Robert Zubrin presented a summary of the arguments in book The Case for Mars, dozens of placards reading “Mars Direct Cowards Return to the Moon” were placed throughout the Carnegie Institute.The passionate uproar among space exploration advocates – both favourable and critical – is an indication of the interest in Mars exploration.
I find the Mars to Stay idea appealing and compelling for both economic and safety reasons. More emphatically, I find it a representation of the spirit of human exploration and discovery. Also personally it is a fulfilment of the ultimate mandate by which manned space programs (US, European, Russian, Chinese, Indian, Japanese etc.) are sold, at least philosophically and long-term, as a step to colonizing other worlds. I hope that Mars One either credibly fulfils this trust or propels alternative programs that deliver human settlement on Mars via a well-defined (i.e. non-suicidal) exploration program.
On May 11, a Dragon will mate with the International Space station. Rather than some mythical creature, this Dragon is of human artifice. The Dragon’s rendezvous and berthing with the International Space Station presages a new chapter in human exploration of space.
The significance of this event is Dragon is a reusable spacecraft, developed, and built by the American company Space Exploration Technologies, SpaceX, as it is more commonly known. Established in 2002, SpaceX has developed a new family of launch and cargo and crew capsules from the ground up.
The commercial race to space
NASA has now “set it sights on exploring once again beyond low earth orbit.
Have you ever had a moment when person responds to you in a way that just makes you feel a little bit older than you did before? You comment, for example, about a music group to someone, only to be met with that incredulous stare that conveys the message to you that their parents liked that music, and that you must be a little older than you at first appeared.
An international research team just gave the Earth such a moment. The researchers did this, not by experimenting on musicians, rather by measuring the radioactive decay of samarium-146; one of the isotopes used to chart the evolution of the Solar System.
By using a more precise technique to remeasure the half-life of samarium-146, they shrank the chronology of early events in the solar system, like the formation of planets, into a shorter time span. It also means some of the oldest rocks on Earth would have formed even earlier. Some Australian rocks forming as early as 120 million years after the solar system formed.
Understanding how a seemingly simple measurement, such as the half-life of samarium-146, can have such far-reaching results will take us on an exhilarating journey through many areas of science.
How did our Solar System form?
According to current theory, everything in our Solar System formed from stardust several billion years ago. Some of this dust was formed in giant supernovae explosions. These explosions then supplied most of the heavy elements for the objects that make up our Solar System. The synthesis of the elements we see on Earth, in rock samples from the Moon and Mars, as well as from meteorites and asteroids, is a subject of great interest. By understanding the physics of the nucleo-synthesis of the isotopes of these elements it has become obvious that the dust and molecules that coalesced to form our solar system came from a number of different processes.
Multiwavelength composite image of the remnant of Tycho's supernova, SN 1572. Photo credit: NASA/MPIA/Calar Alto Observatory, Oliver Krause et al.
The formation of the terrestrial planets (the rocky planets Mercury, Venus, Earth, Mars and their respective moons) is generally divided into three major stages based on the different physical processes involved and their respective time scales: (1) the stardust aggregates into planetismals, like individuals forming into swarms of nomadic tribes; (2) then runaway and oligarchic growth of embryos from planetismals resulting several tens to 100 Lunar- to Mars-mass embryos embedded, like mediaeval barons, in a swarm of remnant planetismals; and (3) the final stage of terrestrial planet formation by high-velocity impacts between embryos over a span of ~10-100 million years, forming the planets as we know them.
The Allende meteorite and the age of the Solar System
The age of the Solar System can be defined as the time of formation of the first solid grains in the nebular disk surrounding the proto-Sun. This age is estimated by dating calcium-aluminium-rich inclusions in meteorites. All chronology, by convention, is referenced to T0, which is the abbreviation for the age of the oldest known solid material in the solar nebula.
Scientists have found that calcium-aluminum-rich inclusions are some of the oldest objects in the solar system. These inclusions, roughly millimetres to centimetres in size, are believed to have formed very early in the evolution of the solar system and had contact with nebular gas, either as solid condensates or as molten droplets.
Relative to planetary materials, calcium-aluminium-rich inclusions are enriched with the lightest oxygen isotope and are believed to record the oxygen composition of solar nebular gas where they grew. Calcium-aluminium-rich inclusions, at 4.57 billion years old, are millions of years older than more modern objects in the solar system, such as planets, which formed about 10-50 million years after them.
In recent research, a US team led by Justin Simon from NASA Johnson Space Centre and University of California Berkeley, studied a specific calcium-aluminium-rich inclusion found in a piece of the Allende meteorite. Allende is the largest carbonaceous chondrite meteorite ever found on Earth. It fell to the ground in 1969 over the Mexican state of Chihuahua and is notable for possessing abundant calcium-aluminium-rich inclusions.
Carbonaceous chondritic meteorites are stony meteorites that have not been modified due to melting or differentiation of the parent body. They formed in oxygen-rich regions of the early, first stage, Solar System so that most of the metal is not found in its free form but as silicates, oxides, or sulfides. Most of them contain water or minerals that have been altered in the presence of water, and some of them contain larger amounts of carbon as well as organic compounds. The Allende meteorite is a ‘pristine’ meteorite, so called because its provenance is known. It was found and sampled under conditions that precluded contamination from terrestrial chemicals and minerals.
Their findings imply that calcium-aluminium-rich inclusions formed from several oxygen reservoirs, likely located in distinct regions of the solar nebula. Calcium-aluminium-rich inclusions travelled within the nebula by lofting outward away from the sun and then later falling back into the mid-plane of the Solar System or by spiralling through shock waves around the Sun.
Through oxygen isotopic analysis, the team found that meteorite material surrounding the calcium-aluminium-rich inclusion show that late in the calcium-aluminium-rich inclusion’s evolution, it was in a nebular environment distinct from where it originated. This latter region was closer in composition to the protoplanetary disk, the environment in which the building materials of the terrestrial planets formed. A protoplanetary disk is an area of dense gas surrounding any newly formed star. In this case, the calcium-aluminium-rich inclusion formed when our Sun was quite young.
Artist concept of proto-planets. Image credit: NASABlueshift
The formation of the Solar System as we know it today, was complex and dynamic process. The protoplanetary disk evolves through accretion to the star, the particles and molecules being gravitational attracted to the proto-Sun. Each particle’s attraction was mediated or dampened by collisions, the viscous drag of the gaseous nebula, coupled with an outward ‘fling’ due to their angular momentum.
Radioactive dating the age of the Solar System
Timescales of early Solar System processes rely on precise, accurate and consistent ages obtained with radiometric dating. The relative abundance of different nuclei and their correlation or non-correlation with models of their formation and their radioactive decay provide a series of clocks to determine when and how material was formed.
Recent advances in instrumentation now allow scientists to make more precise measurements. Some of these measurements are revealing inconsistencies in the ages of samples as well as clearing up existing inconsistencies.
For example, recent analysis, by Audrey Bouvier and Meenakshi Wadhwa from Arizona State University, of the meteorite, Northwest Africa 2364, found that the age of the Solar System predates previous estimates by up to 1.9 million years. They used a radioactive chronometer based on the decay of isotopes of uranium to lead.
By using this lead-lead dating technique these researchers were able to calculate the age of a calcium-aluminium-rich inclusion contained within the Northwest Africa 2364 chondritic meteorite. In lead-lead dating the lead isotope, 207Pb/206Pb ratios are measured; these lead-207 and lead-209 isotopes are the decay products of the uranium isotopes 235U and 238U respectively.
The study’s findings fix the age of the Solar System at 4.5682 billion years old, between 0.3 and 1.9 million years older than previous estimates. This relatively small revision to the currently accepted age of about 4.56 billion years is significant since some of the most important events that shaped the Solar System occurred within the first ~10 million years of its formation.
This relatively small age adjustment means that there was as much as twice the amount of iron-60, a certain short-lived isotope of iron, in the early Solar System than previously determined. This higher initial abundance of this isotope in the Solar System can only be explained by supernova injection. The researchers believe the supernova event, and possibly others, could have triggered the formation of the Solar System. By studying meteorites and their isotopic characteristics, they bring new clues about the stellar environment of our Sun at birth.
This work also helps to resolve some long-standing inconsistencies in early Solar System time scales as obtained by different high-resolution chronometers. The story is not yet complete, it will be important to conduct high precision chronologic measurements of calcium-aluminium-rich inclusions from other pristine meteorites. We also need to understand the reasons why the calcium-aluminium-rich inclusions measured previously from two other chondritic meteorites, Allende and Efremovka, have yielded younger ages.
One significant aspect of this study is that it is the first published lead-lead isotopic investigation that takes into account the possible variation of the uranium isotope composition. Earlier work conducted in Wadhwa’s laboratory by a graduate student Gregory Brennecka, in collaboration with Ariel Anbar, has shown that the uranium isotope composition of calcium-aluminium-rich inclusions, long assumed to be constant, can in fact be highly variable and this has important implications for the calculation of the precise lead-lead ages of these objects.
Using the relationship demonstrated by Brennecka and colleagues between the uranium isotope composition and other geochemical indicators in calcium-aluminium-rich inclusion, Bouvier and Wadhwa inferred a uranium isotope composition for the calcium-aluminium-rich inclusion for which they reported the lead-lead age.
This work can help researchers better understand the sequence of events that took place within the first few million years of the Solar System formation, such as the accretion and melting of proto-planetary bodies. All these processes happened extremely rapidly, and only by reaching such a precision on isotopic measurements and chronology can we find out about these processes of planetary formation.
The importance of the half-life of the isotope samarium-146
As well as the lead-lead dating technique the radioactive chronometer based on the isotope samarium-146 is one of interest for this story. Samarium-146, or 146Sm, is unstable and occasionally emits an alpha particle, a helium-4 particle, which changes the atom into a different element, neodymium-142.
As samarium-146 decays slowly—on the order of millions of years—many models use it to help determine the age of the Solar System. In particular, in models of terrestrial planetary formation, rather than dating calcium-aluminium-rich inclusions in meteorites used in studying early Solar System formation.
Although samarium-146 decays slowly, it is still short compared to the time-scale of solar system evolution. For a known number of any isotope type, the number of years it takes for this to radioactively decay by half of its number, is called its half-life. Since samarium-146 emits particles so rarely, it takes a sophisticated instrument to measure this half-life. The half-life of samarium-146 allows its use as a determinator of the time between the end of its synthesis in the early Solar System and the inclusion of it in a solid body in the solar system.
What scientists look for are disparities in the relative abundances of samarium isotopes in terrestrial rocks and in the relative abundances of samarium and neodymium and neodymium isotopes. The reason for interest in the samarium-146 to neodymium-142 is that the half-life means that samarium-146 present at the time of solidification would no longer be available for observation at the present-time; it all will have decayed to neodymium-142. Therefore the isotopic composition of neodymium will vary with the amount of samarium, which was present at solidification.
The researchers remeasured the half-life of samarium-146 using the sophisticated instrument at the Argonne Tandem Linac Accelerator System, Kanazawa University, and the University of Tsukuba in Japan. What they did was very clever and very precise.
Firstly, they synthesised samples of samarium-146, in three independent nuclear-synthesis reactions, from samples of isotopically enriched samarium-147. The different techniques gave analysis samples with different contaminants and samarium-146 levels. Secondly, they measured the decay of these samples over a period of months using highly accurate detectors.
The Argonne Tandem Linac Accelerator System was then used as a mass spectrometer, in two different experimental set-ups, to pick out the small number of samarium-146 in the samples, one in tens of billions of atoms. These measurements took into account contributions from contaminants such neodymium-146, which caused contamination problems in earlier experiments. Neodymium-146 has the same atomic mass as samarium-146, and in mass spectroscopic measurements they cannot easily be separated.
By accurately counting the number samarium-146 atoms and tracking the particles that the sample emits, the team came up with a new calculation for its half-life: just 68 million years.
This is significantly shorter than the previously used value of 102.6 and 103.1 million years of recent (1966 and 1987 respectively) measurements. At the same time the result is closer to earlier measurements of ~50 million years and 74 million years from 1953 and 1964 respectively.
A new samarium-146 half-life measurement; now what?
The new value patches some holes in current understanding. The new time scale now matches up with a recent, precise dating taken from a lunar rock, and is in better agreement with dates obtained with other chronometers.
Applying this new half-life to rocks from Greenland and Australia gives them revised ages. These rocks are now dated to be 50 million years older than previously thought. That is they were formed only 120 million years after T0, the time of solar system formation, rather than the 170 million years from previous results. Similarly rocks from Quebec were found to be over 80 million years older than previous measurements. These are now found to have formed 205 million years, rather than 287 million years, after Solar System formation. These results illustrate that the events that formed terrestrial rocks occurred at much earlier ages than we even recently thought.
Analyses of moon rock samples have also shown an increase in their ages, in this case by over 70 million years. These are now found to have formed 170 and 175 million years, rather than 242 and 250 million years respectively, after Solar System formation. These new lunar results now bring ages of these rocks, using two different chronometers, the samarium-146 and lead-lead techniques, into the same ranges.
The early days of Earth and the other terrestrial planets are looking quite different than previously thought. All this is thanks to some precision measurements of the half-life of an extinct isotope of an exotic rare-earth element, samarium.
