Wednesday, January 31, 2007

Digging deeper

Researchers from the University College London have suggested in a new paper published January 30th (in the journal Geophysical Research Letters) that finding life on Mars will require deep drilling in choice locations. Because the planet lacks sufficient atmosphere to ward off harmful radiation, there is no chance that microbes could have survived on the surface or even relatively deep within the ground. The researchers estimate that only microbes that have been buried several meters below the surface could survive, but finding such deeply hidden evidence is a task beyond the scope of any hardware presently on Mars. There is a chance that the European Space Agency's ExoMars mission (due to land 2013) could get deep enough, but what we really need are human hands. The new research looked at a number of different soil configurations, to estimate the best likely place to look: dry soil, frozen soil containing layered permafrost, and ice. Ice turns out to be the best medium, with a particularly good target identified as the frozen sea at Elysium, which is thought to have surfaced in the last five million years. Such a geologically young feature will not have received as much radiation as other older areas of the planet, thus increasing the likelihood of some microbes surviving.

Friday, January 26, 2007

Checking the air and water

Conventional wisdom has it that one of two things might explain the lack of air and water on Mars. First is the idea that it simply leaked away over the eons, dribbling away into space as the solar wind stripped molecules from the top of the planet's atmosphere. Another more colourful theory has it that some catastrophic impact blasted the atmosphere away in one titanic event. Either way, the planet now shows little sign of either water or air, though a recent set of photographs snapped from orbit did offer the tantalising possibility that water may still occasionally flow over the surface. Measurements taken previously have suggested the ongoing loss was quite rapid, but new observations from the European Space Agency's Mars Express orbiter are throwing those measurements out, though not necessarily with the bathwater, because that still seems to be there in potentially vast quantities. New figures from Mars Express put the rate of leakage at 20 grams per second of oxygen and CO2, which is 1% of the measured rate by the 1989 Phobos 2 mission. If correct, and extrapolating backwards into its history, it means that Mars has lost a lot less water than air than previously calculated, perhaps only in the region of a few centimetres of water. This is very exciting news, because based on observations of geological formations on the surface, it has been estimated there was once enough water on Mars to fill oceans half a mile deep! So if Mars hasn't lost its water and air, where is it? The only real possibility is underground, which returns us to the fascinating discovery of what looked like a very recent (in the region of years) outpour of water on Mars. Was this little dribble the tip of a huge iceberg buried beneath the Martian sands? Could be, but don't forget the other possibility that a giant asteroid blew away the atmosphere sometime in the distant past. But it certainly is a food for thought (or should that be water to glug and air to breath) because if it is there, locked away beneath the surface, we have even more reason to get a human presence on Mars as soon as possible.

Thursday, January 25, 2007

Mars photo winners announced

NASA has just announced the winners of a survey conducted amongst the public to find the best pictures sent back from Mars by the Spirit and Opportunity rovers. At deserved first place is the hugely evocative moment that Spirit caught the sun sinking beneath the rim of Gusev Crater on May 19, 2005. It's a stunningly beautiful image, simple but haunting. Let's hope that one day in the not too distant future, human eyes get to experience this in person. The site hosting the winners is well worth a visit just to remind yourself of what an amazing achievement the Spirit and Opportunity rovers have been. The relatively small expense of these missions makes the amazing return in terms of science more than worthwhile, but these photographs represent more than just facts and figures. They reveal a world that is both alien and yet strangely familiar. They are the best argument possible for placing a human presence on this most earth like of worlds. See all the pictures from mars here.

Wednesday, January 17, 2007

John Carter bound for Disney?

The idea of a John Carter of Mars movie is almost as old as the books themselves, but it has never managed to escape from development hell. The first attempt came in 1931 when animation pioneer Bob Clampett interested the Burroughs family in the idea of a feature length cartoon. There was considerable interest from Burroughs and his son, and much preparation took place, including the creation of a test reel, but interference from Studio Execs destroyed the project. Several other attempts have been made since, most recently with Paramount pictures. The project even got as far as working through a number of potential directors. Word now comes that since Paramount have dropped the property, there is interest coming from Disney, who see great franchise potential in the project. This is very much breaking news (rumour might be a better word) so take it with a pinch of salt. See tmz for the breaking story.

Thursday, January 11, 2007

New probes go head to head, one crashes and burns

NASA announced on Monday that initial funding had been granted to run feasibility studies on two new Mars missions (as part of the Scout programme) with a tentative launch date for the winning proposal of 2011. Both missions to be considered are concerned with learning more about the upper atmosphere of Mars. MAVEN stands for the Mars Atmosphere and Volatile Evolution mission, and will focus on upper atmosphere dynamics. The "Great Escape mission" (a much nicer name) would perform a similar mission, but might also be able to measure atmospheric constituents such as methane. Both probes are at the very earliest stage of development and some $2 million will be spent over the next nine-months before NASA picks one of the two missions for full development. The total mission cost is expected to be in the region of $475 million. Also announced at the same time was further funding to develop greater ties with the European effort to explore Mars. The full NASA press release can be read here.

Unmentioned in the above press release is the sad news that a great proposal to send an aircraft to Mars was not selected in this round of approvals. Scientists at NASA Langley Research Center in Hampton were understandably disappointed that their trail-blazing idea did not get the go-ahead, but the possibility exists to resubmit the proposal at a later date. The site for the Ares craft is here.

Safe landing for Phoenix proves a rocky road

With a launch due in August 2007, the mission planners for the Phoenix probe to Mars are still struggling to identify a safe landing site near to the northern polar region. The already orbiting Mars Odyssey has been using a thermal camera to look down at night and identify hot spots from cooling rocks on the surface. Unfortunately, the prime landing area proved to harbour a minefields worth of rocks that would make a landing there extremely perilous. The Mars Reconnaissance Orbiter is also getting into the act, using its High Resolution Science Imaging Experiment (HiRISE) camera to take daytime shots. The primary mission of Phoenix is the search for water, hence the importance (and restrictions) of finding a polar landing site. Once down, the probe will use a robotic tool to dig up to 3 feet down into the Martian surface. Space.com has the full story of the ongoing effort to find a safe landing spot.

Monday, January 08, 2007

Viking missions may have killed Martians

A little dramatic perhaps, but a controversy has been rumbling on for many years about the scientific data returned by the 1976 Viking Missions to Mars. For many, the results signalled the final death knell for the long cherished hope that Mars might still harbour some primitive form of life, but not everyone agreed. Conspiracy theorists like to say there was a cover-up of the results, but far more plausible is the belief that the scientists running the probes simply got the results wrong or mis-interpreted them. One such proponent of this theory is Dr. Gilbert V. Levin, who was actually one of the mission scientists in charge of the Viking Labelled Release (LR) experiment. This was designed to detect the uptake of a radioactively tagged liquid nutrient by microbes in the soil. The idea was that gases emitted by these microbes would show the radioactive tagging. Initial results were in line with this prediction but the overall results proved inconsistent. Dr. Levin has since argued vigorously that his experiment did show signs of life, but now we have a new take on the experiment that suggests the probes actually killed any existing Martian microbes. In a paper presented to the American Astronomical Society in Seattle, geology professor Dirk Schulze-Makuch has suggested that the microbes may have been a hydrogen peroxide based life form and that in heating the soil sample during the experiment, the Viking probes would have very effectively killed their intended targets. A NASA scientist is now looking at using the forthcoming Phoenix mission to look into the theory, though it will mean some science on the fly to find a way of adapting the existing instrument package to look for hydrogen peroxide based microbes. ABC News has the detailed story.

Sunday, January 07, 2007

War Of The Worlds gets sporty

It looks like there is a new War Of The Worlds date to enter into your calendars. I have not been able to find a specific website that gives any great detail on this event, but apparently the West Windsor-Plainsboro North school, whose address happens to be none other than 90 Grovers Mill Road, is now into its fourth year of running a large and successful sporting tournament known locally as "The War Of The Worlds." Schools apparently gain points for each win they chalk up, with the grand winner taking home a trophy that resembles the Grover’s Mill red barn where the fictional War of the Worlds story took place in 1938. The competition has been held over several weeks running through to the first week of January. If anyone happens to have any further information on this event and particularly anything that explains the genesis of the event, I would love to hear from you.

Monday, January 01, 2007

Mars rovers get smarter

They were only meant to last a few months on inhospitable Mars, but on January 3rd 2007, the Spirit rover will incredibly begin its fourth year of operation and a few weeks later so will Opportunity. Both rovers have survived many trials, such as jammed wheels and dusty solar panels, but they are also getting smarter thanks to software upgrades beamed to them from Earth. Newly added for 2007 is the ability to pick out significant changes between images, a very useful capability in the search for dust devils. Both rovers have snapped dust devils on Mars, but with the new software, they will be able to pick out the fast moving weather features and beam those specific images back to Earth, saving much bandwidth. Similar thinking will also help the rovers spot interesting cloud formations. Several other upgrades to give the rovers greater autonomy have also been added, and this unexpected chance to test new ideas in live laboratory conditions is sure to provide useful experience for mission planners working on future missions. A detailed review of the upgrades can be found at the spaceflightnow site.