Water droplets appear to be growing on Phoenix’s leg shortly after landing on Mars (NASA)
NASA scientists are currently trying to understand a set of images taken by the Phoenix Mars Lander shortly after it landed on the Red Planet in May 2008. The images in question show one of the robot’s legs covered in what appears to be droplets of liquid water. The droplets remain on the lander for some time, appearing to get larger and changing shape.
By now, we know that liquid water (apparently) hasn’t existed on the Martian surface for hundreds of millions of years; the atmosphere is currently too thin and too cold to support liquid water. However, the confirmed presence of perchlorate in the regolith may provide an important clue as to what might be going on…
$2.2 billion eggs. One basket. The MSL Skycrane lowers the 850kg rover to the Martian surface (NASA)
Don’t get me wrong, I am incredibly excited about any planetary mission, no matter how much it costs. However, there is something about the Mars Science Laboratory (MSL) that makes me uneasy. The project may be delayed (the MSL is scheduled for a 2011 launch) and it may be costing more than NASA projected, but it’s not these factors I’m worried about.
The MSL is built on a “bigger and better” mentality; it dwarfs both of the Mars Exploration Rovers Spirit and Opportunity, plus it is packing a rather impressive suite of 10 complex scientific instruments to carry out an unprecedented campaign in the Martian dirt. Oh, and did I mention it will be powered by radioisotope thermoelectric generators (RTGs), a complete departure from the tried and tested solar panelled rovers? Oh hold on, as the MSL weighs nearly a tonne, a brand new method of landing the thing is required (simply parachuting, air bag bouncing or rocket thruster powered landings are now passé). The “Skycrane” that looks like one of those hoverboards from Back to the Future II has been invented to gently lower the MSL (pictured above).
Still, I’m not too concerned, NASA has proven itself countless times at overcoming technological challenges. That’s why NASA is there, to research and develop new technologies and science. But what if the MSL has gone too far? What if the technology is too untried and untested? Unfortunately, it looks like the recent turn of events have taken even the MSL program manager by surprise…
On Mars, there are no car washes, no windscreen wipers, no rain, no fans... you get the picture. (NASA)
By far the biggest difficulty for robotic operations on the Martian surface are Sun-blocking dust storms. Not only do red-tinted dust clouds block the Sun from penetrating the atmosphere, the dust grains fall on solar panels, creating a layer of dusty sunscreen, reducing the amount of light falling on the photovoltaic cells. This is a special problem for long-term missions on the Red Planet. The rovers Spirit and Opportunity have been pottering around in the Martian regolith for over five years, mission planners had little idea their tough explorers would live much beyond their designed 3 month lifespan; long-term accumulation of dust was of no concern… until now.
Bolide breakup and impact on the surface of Mars (HiRISE/NASA)
Earth has been hit numerous times in recent months by some large chunks of space rock. One of the larger meteoroids to enter the atmosphere was the November fireball over Saskatchewan, Canada. In this case, an estimated 10 tonne meteorite slammed into the atmosphere, creating a bright bolide (fireball), exploding into fragments. Fortunately, eyewitnesses were able to pinpoint the location of possible debris. Sure enough, after an extensive search in the rural area of Canada, meteorite fragments were found.
However, these fragments did not impact the ground at the hyper-velocities that the original fireball was travelling at, the Earth’s thick atmosphere created an efficient barrier, through air resistance, breaking up the bolide. In this case, an energetic explosion was observed for miles around. Fragments from the fireball then fell at a maximum speed of terminal velocity, bouncing off the ground. Some fragments sat proudly on top of frozen ponds – the debris final kinetic energy was so low that little damage would have been done even if the small rocks scattered over a populated area (unless, of course, someone got hit on the head – they would have had a very bad day).
OK, so we’re well protected from most bits of junk space can throw at us. Most meteoroids, from the size of a grain of sand to the size of a small bus, will burn-up, break-up or explode high in the atmosphere, scattering bits on the ground. But what about Mars? What if Mars gets hit by a sufficiently-sized meteoroid?
Even if the meteoroid does break apart, unfortunately the atmosphere is too thin to slow the debris sufficiently. A lack of air resistance makes for more impressive impact craters. Watch your heads future Mars colonists, you could be faced with a shotgun blast from space…
The distribution of atmospheric methane originating from three principal regions on the Martian surface (NASA)
Today, NASA held a press conference detailing some significant discoveries from observations made of the Martian atmosphere. Using NASA’s Infrared Telescope Facility and Keck Telescope, scientists from the University of Hawaii and NASA were able to deduce the spectroscopic fingerprint of methane. Although scientists have known for a long time that methane exists in the Martian atmosphere, the big news is that there is lots of it, it appears to be constantly replenished and it is a huge indicator of biological processes under the surface.
Fortunately, I was able to watch the NASA TV broadcast of the press conference at 11am (PST), so I thought I’d try, for the first time, to do some live microblogging of the announcements using Twitter. So, rather than going into vast detail about today’s methane news (as the web has exploded with articles on the subject anyway), I thought I’d publish my Twitter feed during the conference…
The Mars Reconnaissance Orbiter's HiRISE instrument spots the dead Phoenix Lander on December 21st (NASA/HiRISE)
NASA lost contact with the Phoenix Mars Lander at the start of November 2008, as its batteries were drained and sunlight began to dwindle. With no sunlight came no charge for the batteries from Phoenix’s solar panels, and the robot’s fate was sealed: a sun-deprived coma. A dust storm hastened the lander’s fate, but it certainly wasn’t premature. The Phoenix mission was intended to last three months, but in the same vein as the Mars Exploration Rovers, Phoenix’s mission was extended. In the high latitude location of the Martian Arctic, a dark winter was fast approaching, so Phoenix didn’t have the luxury of time and it transmitted its last broken signal before the cold set in, sapping the last volt of electricity from its circuits…
Although there was some excitement about the possibility of reviving the lander next summer, it is highly unlikely Phoenix will be in an operational state, even if it did have an abundant source of light to heat up its solar panels once more. No, Phoenix is dead.
However, that doesn’t mean the orbiting satellites won’t be looking out for it. So long as there is a little bit of light bouncing off the frosted Martian surface, the Mars Reconnaissance Orbiter can image Phoenix, keeping track of the encroaching ice around its location. The HiRISE team seem to be assembling a series of images throughout the change in seasons at the landing site, so it will be interesting to see the full set…
Source: HiRISE blog
DEM images of Columbia Hills on Mars (USGS/HiRISE)
If there’s one instrument that should get the Mars Orbiting Science Award of 2008 it’s the High Resolution Imaging Science Experiment (HiRISE). Flying on board NASA’s Mars Reconnaissance Orbiter (MRO), HiRISE has been taking some astonishing imagery of the Martian surface since 2006. In fact, the HiRISE image gallery has become the staple of my high resolution Mars photo collection, and the studies being carried out by this fantastic instrument have formed the basis of many articles.
However, the most useful images to come from HiRISE are also the rarest. Digital Elevation Models (DEMs) come from the use of stereo image pairs (more commonly seen in anaglyphs generated by the HiRISE team to give the viewer a 3D impression of the Martian landscape). In the case of DEMs, some pretty neat science can be done, generating images of the Red Planet’s terrain in unrivalled precision. Seeing the Victoria Crater DEM is a particular joy…