Category: Mars

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Google Earth announced a big update today of its Mars features, including a chance to see a continuous stream of new, high resolution satellite imagery just hours after NASA receives them. Called “Live from Mars,” this section features imagery from NASA’s THEMIS camera on board the Mars Odyssey spacecraft, and the HiRISE Camera from the Mars Reconnaissance Orbiter. You can become one of the very first people to lay eyes on images taken just days or even hours ago. You can also see live satellite orbital tracks, or check out where these cameras plan to image next.

But wait! There’s more! Users can also travel back in time to see the Red Planet through the eyes of the pioneers of Mars science in the ‘Historical Maps’ layer by exploring antique maps by astronomers Giovanni Schiaparelli, Percival Lowell, and others. But also, if you don’t know exactly where to start with your Mars exploration, there are guided tours of Mars narrated by Ira Flatow of Public Radio’s Science Friday and Bill Nye the Science Guy, allowing you to enjoy the PB&J (passion, beauty and joy) of the Red Planet through their eyes.

So how do you enjoy these new features? Open Google Earth, and after selecting ‘Mars’ from the toolbar in Google Earth, users fly to a 3D view of the Red Planet, complete with informational layers, imagery, and terrain. The tools for navigation and exploration on Mars are identical to those on Earth – zoom in and out, change the camera view, or spin the entire planet with a click of the mouse.

Just as in the original version of Mars in Google Earth, users can read geo-located articles from Hartmann’s “A Traveler’s Guide to Mars” about the solar system’s largest canyon, Valles Marineris, its tallest volcano, Olympus Mons, the infamous ‘Face on Mars’, and many other famous Martian locations. Users can also follow the paths of Mars rovers and view hi-resolution panoramic photos of the Mars surface.

Google’s Communication and Public Affairs officer Aaron Stein noted the “Live From Mars” imagery is the most current available from the THEMIS camera. ” Our live imagery is the most current available imagery from THEMIS,” he said. “It’s not unusual for NASA to save up and download one or two days of images at a time, so downloads do not always occur within hours of image acquisition. Despite this, Live from Mars is orders of magnitude more “live” than the typical NASA public data release process, which for Mars imagery typically takes many months.”

Enjoy — It’s fun, it’s free, and a great way to lose yourself for a few hours!

Source: Google Earth

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Last month, it was announced that in the few days after the landing of the Phoenix lander in May 2008, the camera attached to the robotic arm captured visual evidence of (what appeared to be) droplets of water, almost like condensation forming on the leg of the lander. In three images dated on sol 8, sol 31 and sol 44 of the mission, the droplets appear to move, in a fluid-like manner. Although a recent publication indicates this oddity could be a water-perchlorate mix (where the toxic salt acts as a potent anti-freeze, preventing the water from freezing and subliming), other members of the Phoenix team are very dubious, saying that there is another, more likely explanation…

One of the key components necessary for the survival of life on Earth is water, especially when the water is in a liquid state. This is an easy proposition on our planet, as the atmospheric pressures and temperatures are just right for the majority of water on Earth to be in a usable liquid state. Should liquid water be discovered on another planet however, where the conditions are often too hot or too cold (or when atmospheric pressure is too low) for water to be found in a liquid state, you’d expect there to be some excitement. When that other planet is Mars, the focal point of the search for basic extraterrestrial life, this excitement will be tempered with intense scrutiny.

In February’s article, Nilton Renno from the University of Michigan and Phoenix mission team scientist, announced results from his team’s research into some odd-looking blobs on one of the lander’s legs. Renno’s hypothesis, to be presented on March 23rd at the Lunar and Planetary Science Conference in Houston (TX), focuses on the possibility that the newly discovered toxic compound, perchlorate, may hold the key to the possibility of liquid water on the Martian surface. We know on Earth, briny (salty) water has a lower freezing point than pure water, and Renno suspects that this might be the case for water on the surface of Mars. However, rather than regular salt, the toxic perchlorate salt is mixed with water in the regolith, allowing it to sustain its liquid state.

Although a very interesting proposition, Renno’s results are based on only photographic evidence of what appears to be blobs of water. Other Phoenix scientists are emphasising that the theory is controversial, citing far simpler answers for the observations.

“There’s a matter of belief at some level,” said Peter Smith from the University of Arizona in Tucson and principal Phoenix investigator. “I can’t say I agree with every statement in the [Renno] paper.”

Michael Hecht, the lead scientist for the instrument that discovered perchlorate in the first place, goes as far to say a perchlorate brine on the Martian surface is very unlikely. Simpler explanations for the apparent dynamic movement of the “liquid” blobs could be attributed to changing shadows. Although perchlorate acts as an efficient “sponge”, condensing water vapour from the surrounding air, the temperatures stated in the paper are actually too warm to form liquid droplets of perchlorate brine.

“I just don’t think it’s the likely explanation,” Hecht said. “It’s just plain old frost, nothing more.”

Looking at the Phoenix images (top), I am a little suspicious about the lifetime of these proposed “liquid” droplets. From sol 8 to sol 44, there is little dramatic change in the locations or sizes of these features. 36 sols of long-term droplets of liquid water seems like a very long time considering the very low atmospheric pressures we are dealing with. Surely liquid brine droplets will dissipate (through evaporation, rather than sublimation) far quicker than 36 sols? Granted, there may be further condensation from the atmosphere (topping up the presence of the liquid), but wouldn’t there be more motion in the blobs if this were the case? This said, I am not familiar with perchlorate brine, so this might well be a characteristic of this cold liquid.

It looks like Renno’s research will make for a very interesting presentation on March 23rd at the Lunar and Planetary Science Conference, sure to provoke a lively debate…

Source: Space.com

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Don’t panic – its only Deimos. But what an image this is of the smaller moon of Mars! HiRISE captured this enhanced-color image of Deimos on February 21, 2009, showing the moon’s smooth surface – with a few impact craters here and there. The one crater near the middle that looks sharp and crisp was created relatively recently. Deimos is composed fragmental rock, or regolith, rich in carbonaceous material, much like C-type asteroids and carbonaceous chondrite meteorites. Deimos is noticeably smoother than Phobos. (See images of Phobos taken by HiRISE in 2008). HiRISE took two images of Deimos, about five and a half hours apart – see below.

These images have a scale of about 20 meters/pixel, so the features 60 meters or larger can be seen. The images were acquired 5 hrs 35 minutes apart, so the sun was to the upper left in the first (left) image and to the right in the second image. Although the viewing geometry is similar in the two images, surface features appear very different due to the changes in illumination.

There are subtle color variations—redder in the smoothest areas and less red near fresh impact craters and over ridges or topographic highs (relative to its center of gravity). The HiRISE scientists say these color variations are probably caused by the exposure of surface materials to the space environment, which leads to darkening and reddening. Brighter and less-red surface materials have seen less exposure to space due to recent impacts or downslope movement of regolith.

Deimos is named after a figure in Greek mythology representing panic or dread. Only two geological features on Deimos have been given names: the craters Swift and Voltaire are named after two writers who speculated on the existence of Martian moons before they were discovered.

More about the operations of taking the images from the HiRISE team.

Source: HiRISE

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This image is probably more suited to Nancy’s “Where In The Universe” series, but judging by the resolution and surrounding landscape, it may be fairly easy to distinguish which planet and what instrument took the shot. Of course, this is Mars and the image was snapped by the astounding HiRISE instrument on board the Mars Reconnaissance Orbiter (MRO). Still… what is it? Apart from looking like a particularly large coffee stain, the answer might not be very obvious. However, once we realise this is an image of an ancient volcano covered with ice, the big question is, why has the ice melted in discrete patches when the rest of the landscape looks like a winter wonderland?

On January 16th, the MRO dashed above the southern hemisphere of Mars, over the famous Hellas impact basin. This large crater is very interesting for many reasons, particularly as the altitude distance from the crater rim to the deepest part of the crater bottom is 9 km. This means there is a 89% increase in atmospheric pressure at the bottom of the crater when compared to the planet average. The pressure is therefore high enough to entertain the thought that liquid water may be a reality in this region (if the temperature gets higher than 0°C that is).

There are also ancient volcanoes in the region, of particular note is the group of volcanoes called Malea Patera (as captured in the HiRISE image above). As Hellas is so close to the southern arctic (antarctic?) region, it is currently entering spring time, surface ice is beginning to melt as the Sun creeps higher above the Martian horizon. However, there appears to be areas of ice that are melting faster than others, and a pattern is emerging.

At first, I looked at the images and thought that there may be some heat being released from thermal vents in the volcanic region. However, HiRISE scientists have another explanation for the dalmatian spots that have appeared. On Earth, we will often find dark rocks that appear to have melted the snow from around them during a sunny day. This is because the sunlight will penetrate the snow and heat up the darker rocks quicker than the lighter rocks. Dark rocks will absorb solar energy faster than the more reflective light rock, dark rocks heat up faster, snow surrounding dark rocks melts quicker.

This basic ice melting mechanism is being singled out for what HiRISE is seeing on this ancient volcanic region. There are patches of dark rock melting the snow faster than the rest of the region as the Sun gradually heats the southern hemisphere. What is very interesting is the patches and shape of the melt region. Could it be an ancient lava outflow from a volcano? Are the patches sand dunes peppered with volcanic material? Or is there some other explanation? HiRISE scientists hope to take more images of Malea Patera as the seasons roll on to see how the ice continues to melt. It will be interesting to see what HiRISE finds under the ice during the summer…

Source: HiRISE

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Its pictures like these that put the Mars Program into perspective for me. We have two operational rovers that have rolled across the Martian landscape for five years (when they were designed to last only three months), and we have three satellites orbiting Mars carrying out a variety of key scientific studies. For one of the instruments orbiting over 250 km (155 miles) above the Red Planet on board the Mars Reconnaissance Orbiter (MRO), it is fulfilling the “reconnaissance” duties of the MRO rather nicely. The High Resolution Imaging Science Experiment (HiRISE) is helping out its roving buddy, Opportunity, to plot the best route through the undulating sandy dunes of Meridiani Planum. Robots helping other robots on Mars…

We’ve seen shots like this before taken by the high resolution camera used by HiRISE. From spotting the Phoenix Mars Lander repeatedly throughout 2008 to keeping a watchful eye on the progress of both rovers, the instrument has been an invaluable tool for NASA scientists to see what the landscape is like around the tough wheeled robots.

As another sol rolls on, MER Opportunity clocks up some more distance on its epic two year journey toward Endeavour, a crater 20 times larger than Opportunity’s previous crater subject, Victoria (now a feature shrinking in the rover’s rear view mirror). The rover has a long way to go, but should Opportunity survive the trip, it will be a momentous achievement. After all, the rover will be seven years old at that point.

For now, HiRISE is aiding the planning of Opportunity’s drive through the open Mars desert. As can be seen in the HiRISE image to the left (detail from the main image, top), 1783 sols into its mission, the rover is still going strong. The day before this image, Opportunity had driven 130 metres over the sand dunes. Generally, these dunes are mere ripples in the regolith, but some can be too big for Opportunity to traverse. However, HiRISE will spot any hazard well in advance, and NASA can plan Opportunity’s route accordingly.

So Opportunity roves on toward the southeast target of the Endeavour crater, about 17 km away. But HiRISE will be watching…

Source: HiRISE

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A new study of gullies seen on Mars provides evidence that water flowed recently on the Red Planet, at least in geologic terms. Planetary geologists at Brown University have found a gully fan system on Mars that formed only about 1.25 million years ago. The structure of this fan offers compelling evidence that it was formed by melt water that originated in nearby snow and ice deposits. This time frame may be the most recent period when water flowed on the planet. This most recent finding comes on the heels of discoveries of water-bearing minerals such as opals and carbonates, and together all these discoveries provide clues that Mars was, at least occasionally, wetter and warmer for far longer than previously thought.

While gullies are known to be young surface features, it’s difficult to date them. But the Brown scientists were able to date the gully system because of craters in the area, and also hypothesize what water was doing there.

The gully system shows four intervals where water-borne sediments were carried down the steep slopes of nearby alcoves and deposited in alluvial fans, said Samuel Schon, a Brown graduate student and the paper’s lead author.

“You never end up with a pond that you can put goldfish in,” Schon said, “but you have transient melt water. You had ice that typically sublimates. But in these instances it melted, transported, and deposited sediment in the fan. It didn’t last long, but it happened.”

The gully system is located on the inside of a crater in Promethei Terra, an area of cratered highlands in the southern mid-latitudes. The eastern and western channels of the gully each run less than a kilometer from their alcove sources to the fan deposit.

Viewed from afar, the fan appears as one entity several hundred meters wide. But by zooming in with the HiRISE camera aboard the Mars Reconnaissance Orbiter, Schon was able to distinguish four individual lobes in the fan, and determine that each lobe was deposited separately. Moreover, Schon was able to identify the oldest lobe, because it was pockmarked with small craters, while the other lobes were unblemished, meaning they had to be younger.

Next came the task of trying to date the secondary craters in the fan. Schon linked the craters on the oldest lobe to a rayed crater more than 80 kilometers to the southwest. Using well-established techniques, Schon dated the rayed crater at about 1.25 million years, and so established a maximum age for the younger, superimposed lobes of the fan.

The team determined that ice and snow deposits formed in the alcoves at a time when Mars had a high obliquity (its most recent ice age) and ice was accumulating in the mid-latitude regions. Sometime around a half-million years ago, the planet’s obliquity changed, and the ice in the mid-latitudes began to melt or, in most instances, changed directly to vapor. Mars has been in a low-obliquity cycle ever since, which explains why no exposed ice has been found beyond the poles.

The team tested other theories of what the water may have been doing in the gully system. The scientists ruled out groundwater bubbling to the surface, Schon said, because it seemed unlikely to have occurred multiple times in the planet’s recent history. They also don’t think the gullies were formed by dry mass wasting, a process by which a slope fails as in a rockslide. The best explanation, Schon said, was the melting of snow and ice deposits that created “modest” flows and formed the fan.

The team’s findings appear in the March issue of Geology.

Source: Brown University