Image: Curiosity's tire tracks from its first
Alien Robots That Left Their Mark on Mars
Aug. 24, 2012 --
Since the dramatic powered landing of NASA's Mars Science Laboratory (MSL) on Aug. 5/6, the one-ton rover has achieved a number of "firsts." It was the first planetary mission to use the exciting Sky Crane maneuver; the first to shoot lasers (for science); it's even the first nuclear-powered rover to put tread marks into Martian dirt. But it certainly isn't the first rover on the Red Planet -- two generations of Mars rover came before it. And the numerous stationary landers have also left their mark. To any hypothetical Martians on the Red Planet, it may look like an alien invasion is underway -- but these aliens come from the Blue Planet and they seem to insist on sending wave after wave of increasingly sophisticated robotic probes that dig, burn, scour and damage their pristine landscape! So, as we watch the incredible Curiosity rover dominate Gale Crater, it's time to take a step back and contemplate how these surface missions have changed the Martian landscape.
Image: Sojourner investigates a rock a short
The First Rove As we ooh and aah over Curiosity's plus-sized wheel marks, it's time to turn the clock back to 1997 when a 2-foot long wheeled robot made its first, tentative sojourn onto Mars. NASA's Mars Pathfinder mission was the first successful rover mission to the Red Planet (the first attempts were the Soviet Mars 2 and Mars 3 surface missions in 1971 -- both failed) that saw the Sojourner rover explore its landing site for over 80 days after landing on July 4. Its primary mission was only seven days. The little rover left behind plenty of tire tracks that likely persisted for some time after the mission concluded -- they probably quickly became filled with Mars dust and eroded by winds.
Credit: NASA/JPL-Caltech/University of Arizon
Orbital Tracks The immensely successful Mars Exploration Rover (MER) Opportunity is in its ninth year of operations since landing on Mars on Jan. 25, 2004. As the rover continues to explore the Red Planet, notching up over 20 miles on the odometer (so far!), it has also left an impressive history of tire tracks. Amazingly, these tracks can be seen from orbit and NASA's Mars Reconnaissance Orbiter (MRO) has been able to keep a close eye over its roving cousin from space using its High-Resolution Imaging Science Experiment (HiRISE) camera. In this orbital snapshot, Opportunity can be seen at the edge of Victoria Crater (in 2006), plus wheel tracks. Like Sojourner, these tracks are not permanent, Mars' weather will erode them over time. So it's fortunate that Opportunity is still roving, creating new tracks.
Image: A photograph by Spirit shows the obvio
Trench Digging MER Spirit, Opportunity's ill-fated sister rover, also surpassed her "warranty" by five years after landing on Mars on Jan. 4, 2004. Sadly, after becoming immobilized in a sand trap inside Gusev Crater in 2009, rescue attempts failed and the rover was confirmed lost after it stopped transmitting in March 2010. Spirit didn't travel as far as Opportunity -- logging nearly 5 miles -- and had a harder time on the surface of Mars. Early in the mission on March 13, 2006, one of the rover's wheels ceased working, forcing rover drivers to drive Spirit backwards, dragging the dead wheel behind it. Serendipitously, the frozen wheel became a handy trench-digger, creating a deep groove in the loose top soil as it roved. Material that would have otherwise been inaccessible could be glimpsed. Spirit's roving tracks will therefore likely remain visible on Mars for some time to come due to a sticky wheel.
Image: One of the Rock Abrasion Tool (RAT) ma
Branding Rocks But it's not just tire tracks Spirit and Opportunity left on Mars, they have created a rather more permanent calling card. Using the rock abrasion tool mounted to both rovers' robotic arms, the wheeled robots have scoured the surface layers off a number of rocks for scientific study. On each rock, a 45 millimeter diameter circular "branding" has been left behind.
Image: The view of a rock plus fresh laser sc
Laser Tattooing Rocks Although tagging rocks with circles is certainly cool (and of high scientific merit), the new rover on the Mars block has been outfitted with an instrument to laser-blast rocks with. Curiosity's ChemCam instrument mounted atop its mast can shoot rocks at a distance with a powerful laser beam, burning the surface layers. The resulting flash of light contains information about the rock's constituents, which ChemCam analyzes. Like Spirit and Opportunity, Curiosity can leave its own calling card -- a tiny, permanent laser'd tattoo.
Bouncy Bouncy Landing on Mars is serious business, and some very inventive methods have been used. The 1997 Mars Pathfinder mission, for example, touched-down with a bounce -- airbags were deployed, ensuring a cushioned impact with the ground after descent through the atmosphere. Airbags were also deployed during the landings of Spirit and Opportunity in January 2004. In this photograph, Opportunity retraced its bounce-marks to see impressions of the airbags preserved in the Martian regolith. The bags' seams can be seen. As the airbag bounce only imprinted the uppermost surface, it's likely these impressions were rapidly blown away and/or covered with dust.
Image: Two craters formed by Curiosity's rock
Rocket Excavation Of course, Curiosity has to go one-better than its predecessors. During the powered landing of the rover, the Sky Crane's rocket-powered assembly delivered a huge amount of thrust to make sure Curiosity had a soft landing (air-bags aren't a viable landing method when delivering a rover the size of a car). Although debris was blown atop the rover, potentially damaging a wind sensor, the maneuver was a resounding success. But evidence of the landing has been spied around the rover. Areas of excavated material, creating shallow craters, surrounded the rover after landing. This ended up being a fortuitous event -- loose surface layers of dust and gravel were blown away, exposing the bedrock of Gale Crater. The bedrock has been the focus of study and the craters will likely be some long-term scarring of the Martian surface.
Credit: NASA/ JPL-Caltech
Crash and Burn Although the Sky Crane landed Curiosity safely to the surface, the rocket-powered platform suffered a messy demise. After its job was done, it throttled-up and flew far away from the rover, ditching into the Mars landscape. This HiRISE image shows the carnage that the Sky Crane's mass left behind after impact -- a site to remember the Sky Crane's good work.
Credit: NASA/JPL-Caltech/University of Arizon
Man-Made Meteorites Shortly after Curiosity entered the Martian atmosphere, as it began its descent, the rover's aeroshell (a capsule composed of a heatshield and backshell) jettisoned six 55-pound (25-kilogram) tungsten slugs to improve its stability as it used the Martian atmosphere to steer to its target. These ballast slugs slammed into the Martian surface -- basically man-made meteorites -- and could be spotted from orbit.
Image: Phoenix's scoop it used to excavate th
Phoenix With all the excitement surrounding rovers, it's about time to remember the not-so-mobile Mars explorers. On May 25, 2008, NASA's Phoenix Mars Lander touched down in Mars' arctic region to carry out experiments in a region we know little about. Using its arm-mounted scoop, the lander was able to retrieve samples from the freezing ground, dropping the material into its chemical laboratory for analysis. Phoenix made the landmark discovery of perchlorate in the soil and found water ice (that slowly sublimated) in the uppermost layers of the permafrost. Although Phoenix was never going to last long -- the arctic winter most likely cocooned the robot in ice. By Nov. 2, 2008, the mission was declared lost. Surrounding the landing site, however, small trench marks will likely remain -- remnants of Phoenix's science.
Image: The view from Viking 1, with trenches
The Trendsetter NASA's first landers also left their mark on Mars. The Viking landers were hugely successful, returning the first images from the Martian surface and carrying out a suite of experiments to directly search for microbial life. Viking 1 lasted from July 1976 to November 1982; Viking 2 lasted from September 1976 to April 1980. To this day, the Viking experimental results are debated, but the deep trenches that were dug likely remain behind. MORE: Mars Curiosity 'Litter Bug' Spied from Orbit: Photos
As if NASA didn’t have enough to worry about, the U.S. space agency is now faced with the scandal of the century — they’re being sued for not investigating a bona fide life form on Mars!
Whoa, that’s a biggie.
Except, it isn’t. In fact, it’s quite funny.
Remember when news broke about the mystery Mars rock that mysteriously appeared in front of Mars rover Opportunity? Well, according to petitioner Rhawn Joseph, the official explanation for said “mystery” rock — that scientists have dubbed “Pinnacle Island” — is a complete sham. Why? Well, through flawless reasoning skills, Joseph thinks that this is in fact proof of alien life on Mars and NASA is unwilling to investigate any further.
Joseph says it is actually a “mushroom-like fungus, a composite organism consisting of colonies of lichen and cyanobacteria, and which on Earth is known as Apothecium.”
For an agency that is currently looking for habitats comfy for life as we know it, it sounds grossly negligent that one of their rovers should see a Martian Spongebob Squarepants pop up in front of its camera only for it to be fluffed over as “just a rock.”
According to the writ, Joseph wants to:
“… compel and order the National Aeronautics and Space Administration (NASA) and its Chief Administrator Charles Bolden, to perform a public, scientific, and statutory duty which is to closely photograph and thoroughly scientifically examine and investigate a putative biological organism which was identified (and thus discovered) by Petitioner, and photographed on Mars by NASA’s Mars’ rover Opportunity in January 2014, and which NASA referred to in a press release as: “unlike anything we have seen before… We are totally confused.”
(I’m not quite sure how Joseph “discovered” the “organism,” but as this writ is pure fantasy anyway, Joseph may as well throw in some more nonsense.)
Indeed, at the “10 Years On Mars” meeting at Caltech, Pasadena, Calif., earlier this month, lead scientist of NASA’s Mars Exploration Rover Opportunity Steve Squyres did say the origin of the object in question was a mystery and that it had his team baffled as to where it came from. There was never any doubt that was still just a rock. Raw images of the rock and preliminary analyses were discussed and potential sources for the rock were highlighted. The leading theories are, 1) the rock is in fact impact ejecta from a nearby meteorite fall or, b) the rock was flipped out of place by the rover as it turned on the spot. Lacking corroborating evidence, Squyres indicated that the latter explanation was the most likely.
And now, after further analysis of images taken by Opportunity, there’s a divot just beneath the rover that may well be the source of the flipped rock.
No way! says Joseph. Sadly, it seems he hasn’t heard about Occam’s Razor — among competing hypotheses, the hypothesis with the fewest assumptions should be selected (in this case, the Mars aliens hypothesis requires a whole boatload of assumptions) — a fact that is troubling considering Joseph says he’s an astrobiologist with a long string of papers published in “leading journals.” But he’s also affiliated with the questionable Journal of Cosmology that has a habit of publishing below-par research on alleged aliens in meteorites and aliens floating in the upper atmosphere, so that may explain a few things.
As he’s already burnt a few bridges as to his scientific reasoning skills, Joseph decides to go personal, saying, “(a)ny intelligent adult, adolescent, child, chimpanzee, monkey, dog, or rodent with even a modicum of curiosity, would approach, investigate and closely examine a bowl-shaped structure which appears just a few feet in front of them when 12 days earlier they hadn’t noticed it. But not NASA and its rover team who have refused to take even a single close-up photo.”
Joseph obviously doesn’t use the internet as Opportunity has returned many close-up photos of the Mars rock that, by the way, was already being treated as an immensely valuable science target.
As the writ has no foundation, especially as Opportunity has already done some pretty thorough analysis of the rock using its suite of cameras and microscopic imager, this is just an attention-seeking effort that highlights the day-to-day frustrations scientists face when confronted with individuals with overactive imaginations. The real search for extraterrestrial life is far more interesting and a little more scientific than thinking you can see a fungus growing from the Martian surface.