The ESA probe Mars Express flew past the Martian moon Phobos today. Great image!
A Mars map app for Android phones.
New research confirms that the Viking landers did find organics on Mars back in the 1970s. Listen also to the September 15, 2010 and September 23, 2010 radio interviews that John Batchelor and I did with Viking project scientist Gilbert Levin and Christopher McKay of the Ames Research Center on this very subject.
In its 14 mile multi-year trek to Endeavour Crater — now about half completed — the Mars rover Opportunity has stopped to take a short rest stop at a small crater.
The crater, dubbed “Santa Maria Crater” by the scientists who operater Opportunity, is about the size of a football field. What makes it especially interesting are the sharp rocks piled up on its rim, as they are probably debris ejected from the crater at impact. Since this material probably came from deep below the Martian surface, it is also likely to hold information about the Martian geological past, thereby making it a prime research site.
The uncertainty of science: Did the Martian methane signal come from Earth?
The hubbub about this week’s lunar solstice eclipse was, from my perspective, mostly manufactured press blather. For those who had never seen a lunar eclipse, it was a spectacular experience, but there really was nothing scientifically or technically unique about the fact that it happened to occur on the solstice.
However, below is an eclipse that is definitely unique both technically and scientifically. Scientists using the Mars rover Opportunity have filmed an eclipse on Mars, showing the Martian moon Phobos crossing in front of the Sun. Consider the engineering accomplishment: not only did they need to be able to calculate exactly when this would happen at a very particular spot on the Martian surface, they had to have a camera there able to take the movie. And they had to operate it from Earth!
And damn, do I want to rappel into them!
This week’s release of images from the HiRISE camera on Mars Reconnaissance Orbiter included these spectacular photos of two deep pits, approximately 180 and 310 meters in diameter and located aligned with a series of depressions that suggest additional passages at their base.
The first image shows the pits in the context of the surrounding terrain. From the caption:
These pits are aligned with what appears to be larger, degraded depressions. The wispy deposit may consist of dark material that has been either blown out of the pits or from some other source and scattered about by the local winds.
The next two images are heavily processed close-ups of each pit in order to bring out the detail within. From the caption:
The eastern most and smaller of the two pits contains boulders and sediment along its walls and brighter aeolian dune sediments on its floor. The larger, western most pit contains sediment and boulders with faint dune-like patterns visible on the deepest part of the floor. Both pits have steep eastern walls and more gently sloped western walls that transition gradually into the pit floor. Steep resistant ledges containing boulders that overhang and obscure the pit floors form the eastern walls.
The image below from Mars Reconnaissance Orbiter shows gullies remarkably similar to gullies formed on Earth by flowing water, thus providing striking evidence that at some time in the past liquid water did flow on the Martian surface, something that is not possible now. Key quote from the caption:
The gullies shown in the subimage (approximately 710 x 1100 yards) have well developed alcoves, deeply incised channels, and large depositional fans, and are similar to terrestrial landscapes sculpted by surficial water.
The gullies shown in the subimage experienced several periods of activity, as evidenced by older channels cut by younger ones or by their deposits. The current and recent Martian temperatures and atmospheric conditions would not allow for water to be stable at the surface for extended periods of time: it is so cold that the water would freeze, and then it would sublime quickly, because the air is very thin and dry. These gullies could have formed under a different climate, or maybe by repeated bursts of transient fluids. Current leading hypotheses explaining the origin of gullies includes erosion from seepage or eruption of water from a subsurface aquifer, melting of ground ice, or dust-blanketed surface snow.
Those who visit this website regularly know that I repeatedly post images from the various Mars orbiters and rovers. I do this not only because the images have scientific interest or that they are cool, but because it is simply fun to sightsee, even if it is done by proxy using a robot many millions of miles away. Here are two more images of the sights of Mars.
The first is a mosiac image of a small crater that the rover Opportunity strolled past on November 9 in its four year journey to Endeavour Crater.
What always amazes me about the images that Opportunity has taken as it travels across the Martian desert is how totally lifeless this desert is. You would be very hard-pressed to find any desert on Earth like this. On Earth, life is everywhere, even in deserts with their harsh environment. Moreover, life on Earth has reshaped the surface drastically. Environmentalists like to whine about the havoc humans wreck on nature, but the truth is that all life does this continually. Plants and trees help soften the terrain. Animals (not just humans) mold the surface to their needs.
On Mars, however, all one sees is wind-strewn sand across barren bedrock. What this suggests is that, if there is life on Mars, it is well buried, not very visible, and possibly quite rare. It will thus be difficult to spot.
The second image is another one of those Martian collapse features, where some form of fluid flow under the surface washed out the supporting material. causing the surface to eventually collapse. In this case, however, the collapse left at least one natural bridge. Based on the scale (25 cm = 1 pixel), this bridge is about 80 feet wide and 100 feet long. (To calculate its height requires more mathematical skills than I have.)
Boy, wouldn’t this be a magnificent thing to hike under and across!
Go to sleep for science and space exploration.
The first tests in Antarctica of a drill designed to drill cores on Mars.
Is Spirit, the Mars rover, finally dead?
Caver alert! Releases this week from both the Mars Express orbiter and the Mars Reconnaissance Orbiter show a variety of sinkholes and collapse features on Mars, which in turn suggest the possibility of underground passages.
First, there is this picture from Mars Express, showing the area called Phoenicis Lacus (Latin for Phoenix Lake).
The large and long canyon in box 1 is actually a collapse feature, almost two miles deep and formed as this region was stretched, warped, and cracked by the powerful volcanic activity of the nearby giant volcanoes of the Tharsis plateau, including Olympus Mons, the solar system’s largest volcano. You can also see how this activity causes several sinkholes and craters in all three boxes to become elongated and distorted.
In places where the surface is deformed in this way on Earth, you often find tectonic caves, underground cracks produced as the ground is pulled apart. The large collapse feature suggests the possibility that there are voids below it.
Then there is this subimage from this release of Mars Reconnaissance Orbiter, showing the central peak and southern slope of an old crater in the Terra Sirenum region of the Martian southern hemisphere.
Down that south slope can be seen what look like fluvial-like flows. In the center of these flows as well as near the top of the peak are what appear to be a string of collapse features. Below is the close-up as indicated by the box above:
From the caption: “It is possible that these pits are evidence of subsurface piping or hydrothermal activity. Piping occurs when subsurface water flows through soil, takes some soil with it, and causes the overlying ground to collapse. These fluvial-like features and the connected pits may have formed during a late stage of crater formation when temperatures were suitable for liquid water.”
On Earth, this is one of the geological processes that forms sinkholes on the surface as well as caves underground. When cavers go out to look or dig for new caves, we often head for just this kind of string of sinkholes, as they are excellent evidence that an unentered cave lies hidden below, ripe for exploration.
Opportunity’s long journey across the desert plains of Mars to reach Endeavour Crater is now more than half completed. Below is the most recent mosiac of its view heading east towards the crater, with the crater’s rim visible on the distant horizon, still five miles away.
Evidence of subsurface water has been found by the Mars rover Spirit at the location where the rover remains stuck.
A paper published on Saturday in the Journal of Geophysical Research – Planets of the American Geophysical Union, scientists suggest that the polygonal shaped cracks seen in the crater floors on many Martian craters could be evidence of ancient lakes. The evidence also suggests that the lakes were formed by the impact that created the crater. The energy of the impact melted underground ice to form a temporary lake inside the crater, which eventually dries out, leaving behind the polygons. From the abstract:
We propose desiccation to be a dominant mechanism for the formation of Crater Floor Polygons without ruling out thermal contraction as a possible contributor in some cases. This implies that lakes or water-rich sediments occupied the craters in the past. Many such aqueous environments have no apparent external source of water, and thus, hydrothermal processes occurring shortly after the impact event may be viable explanations for the observed evidence.
Mars Reconnaissance Orbiter has taken this image of what appears to be a recent landslide on Mars, located on the southeast wall of Zunil crater. When the landslide took place is not known, though the color suggests that it happened so recently that the debris has not yet been covered by wind-blown dust.
Steve Squyres of Cornell University and the project scientist of the Mars rovers Spirit and Opportunity spoke today at an astrobiology symposium in Arlington, Virginia. He described several spectacular planetary missions that might be flown in the coming decade. All are being considered. None have yet been chosen or funded.
Squyres is the co-chair of a committee of the National Science Foundation that is right now putting together a decadal survey for outlining unmanned planetary research for the next decade. This survey is expected to be released in March, which is when we will find out which of the above missions the planetary science community prefers.
The discovery by scientists of carbonate rock deep below the Martian surface suggests the planet once had a rich carbon dioxide atmosphere. It also suggests that conditions might be more habitable for life deep underground.
From a session today at the 42nd meeting of the AAS Division for Planetary Sciences: After thirteen years of searching, scientists have concluded that Mars has no active volcanic activity, including geysers, anywhere on its surface.
The HiRise Camera on Mars Reconnaissance Orbiter has released some wonderful new pictures, showing what are called barchan dunes on Mars.
Barchans are crescent-shaped, with the horns of the crescents pointing downwind. One barchan is visible in the upper part of the image, with the Southeast (lower right) horns longer than the other. This trend, along with the position of the steep face of the dune on the South side, indicates that the predominant winds which formed the dunes came from the North.
There are a lot more great images on the websites above.
The view from Opportunity, September 16, 2010. Near the rover you can see the bedrock periodically exposed under windblown sand. The rock sitting on the sand in the distance is thought to be a meteorite, to which Opportunity is heading for a closer look. In the distance can be seen the rim of Endurance Crater, the rover’s eventual destination.
Among the new images posted last week by the HiRise camera on Mars Reconnaissance Orbiter is a picture showing the layered and looping ridgelines within Galle Crater. A close-up of these ridgelines revealed the precarious nature of those crumbling cliff tops.
Below is a low resolution version of the image, with a high resolution cropped inset below that, showing a close-up of the most interesting looking area. In the inset you can see that the top of the cliff has separated away. It almost looks as if several large pieces are about to break off. You can also see that the top of the cliff to the north is made up of hanging rocks that appear to almost float in the air. They too look as if they are about to break off.
What makes this even more intriguing is that there are no boulder piles at the bottom of any cliff. All we can see on the valley floor is a pattern of polygonal fractures, possibly “due to ground ice, or regional tectonic stresses.” If large pieces of these ridge lines are breaking off periodically, as they surely appear to be doing, where has the debris gone?
Research results posted today [pdf] at the European Planetary Science Congress show that the methane in Mars’s atmosphere is seasonally variable and far more short-lived than predicted, disappearing in less than a year. Some process, therefore, must be both using it and replenishing it. On Earth, that’s almost always done by some form of life process. Key quote by one of the scientists, from the press release:
“Only small amounts of methane are present in the martian atmosphere, coming from very localised sources. We’ve looked at changes in concentrations of the gas and found that there are seasonal and also annual variations. The source of the methane could be geological activity or it could be biological we can’t tell at this point.”
The image below shows the three regions (in yellow) where the methane is concentrated.
For the fifth time in two years Mars Reconnaissance Orbiter has gone into safe mode because of a computer reboot.
On August 18, 2010, the Mars rover Opportunity took this panorama image of the Martian terrain. Up close, patches of bedrock can be seen where the sand had blown clear. In the far distance the rim of Endeavour Crater, the rover’s long term destination, pokes up over the horizon.
Update: A press notice from JPL today notes that Opportunity has now traveled about half of the 11.8 mile distance to Endeavour Crater. As it took two years to go this far, the journey still has two years to go, assuming the rover survives that long.
