Sublime Ground

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Credit: NASA/JPL-Caltech/University of Arizona
/Texas A&M University

Any doubts that Phoenix might have landed on the wrong spot have been dispelled, as the white layer dug up by the robot's arm has been seen to be subliming* away over time - confirming, according to NASA scientists, the existence of ice.

*The low temperature and pressure on Mars conspire to make liquid water impossible to exist, so when ice heats up it will instead sublime straight to water vapour.

Oh, and a Sol is a Martian day, but you knew that. ;-)

Hundreds and Thousands

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Credit: NASA/JPL-Caltech/University of Arizona

I'm still settling in to my new computer (here's something you can do right now: burn a CD of all the free programs you've downloaded, so you won't have to find them all again), so here's a pretty picture: Martian soil sprinkled on a blob of silicate and photographed by Phoenix's microscope. The white bar in the bottom left shows the scale of one millimetre.

Ice Beneath

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Credit: NASA/JPL-Caltech/
University of Arizona/Max Planck Institute

"We were expecting to find ice within two to six inches of the surface," said Peter Smith of the University of Arizona, Tucson, principal investigator for Phoenix. "The thrusters have excavated two to six inches and, sure enough, we see something that looks like ice. It's not impossible that it's something else, but our leading interpretation is ice."

Camera on Arm Looks Beneath NASA Mars Lander

Of course, we've seen ice on Mars before, from orbit, but we've never before been within (robotic) arm's length of the stuff. Any worries that the immobile Phoenix lander might be sitting on the wrong spot have surely been allayed a little, though it's not until we actually start digging that we'll know for sure.

Arctic Martian Postcard

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Credit: NASA/JPL-Caltech/
University of Arizona/Texas A&M University

I always like an image from space that includes a part of the spacecraft. It gives a great sense of immediacy, of presence. Hence the image above, from Phoenix.

Phoenix has been wiggling its arm, looking around, and shining a laser at the sky. It's all fun and games when you're a robot on Mars - until the ice begins to encroach, at least.

Ice and Phoenix

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Credit: NASA/JPL-Caltech/University of Arizona

Someone who is feeling very healthy this (Earthly) morning: NASA's Phoenix, successfully landed on the Martian arctic. No ice visible yet: but that's expected to change over the next three months, culminating ultimately in the craft failing due to the intense cold, half-buried beneath perhaps a metre of carbon dioxide ice.

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Credit: NASA/JPL-Caltech/University of Arizona

The operational limit on the Mars Rovers, you may recall, was anticipated to be when their solar panels became completely covered in dust - an event that ultimately never occurred due to frequent gusts of wind. Phoenix is a stationary lander, but its own solar panels are pretty nifty: fan-like things that only gracefully unfurled once the dust thrown up during landing had settled.

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Credit: NASA/JPL-Caltech/University of Arizona

You may have noticed that Phoenix was pretty quick with the colour images compared to many missions. This is a good sign, but also a bit cheeky. Cheeky because these are 'approximate' colour images. But a good sign, I think, because rushing out some less-than-faithful colour images early shows that the folks behind Phoenix have learnt from the good example of Cassini (and the not so good example of a few other space missions) that it's important to capture the public's interest with striking imagery. Although more scientifically useful data is what will ultimately expand our knowledge (and awe) of the Solar System, it's the way these robots lend us the ability to vicariously experience its sights that makes us so eager to send them out in the first place.

The next big news from Phoenix will be once it has tried sampling the surrounding ice and permafrost, unlocking secrets about the history and habitability of the red planet.

48 Degrees North

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Credit: NASA-JPL

Eleven days until Phoenix touches down. I'm kind of hoping for a significantly different view of Mars from anything we've yet seen from the ground. Phoenix will be landing at about 68 degrees north, while Viking 2, which provided the image above, experienced the most polar conditions of any (surviving) lander so far, at a relatively balmy 48 degrees north. The white-ish parts of this image are a thin layer of water frost.

And no, it's not just you. Viking 2 landed on a rock, and as such was at a funny angle. Not something that rovers have to worry about, but a big concern among Phoenix's fretful parents, I'm sure.

Red Dust

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Credit: NASA/JPL

Opportunity's ageing shoulder is starting to experience arthritis; and it's now only 26 days until Phoenix touches down.

Telephoto Phobos

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Credit: NASA/JPL-Caltech/University of Arizona

My one complaint is that Mars Reconnaissance Orbiter didn't turn its absurdly powerful camera on one of the Martian moons sooner. Presumably some careful conjunction of orbits was required. See the rest of the images here.

Phobos is an almost microscopic 27 km across at its widest point, and orbits Mars in a mere 8 hours. It hugs so close to the equator of its mother planet, that it can't even be seen from higher Martian latitudes.

Landslides on Mars

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Credit: NASA/JPL-Caltech/University of Arizona

Mars Reconnaissance Orbiter chanced upon this rare image of the Martian environment in motion.

Ingrid Daubar Spitale of the University of Arizona, Tucson, who works on targeting the camera and has studied hundreds of HiRISE images, was the first person to notice the avalanches. "It really surprised me," she said. "It's great to see something so dynamic on Mars. A lot of what we see there hasn't changed for millions of years."

The photo has significant implications for the study of Martian geology (perhaps more properly 'areology'), and is damn pretty to boot.

Across the Martian Canyon

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Credit: ESA/ DLR/ FU Berlin (G. Neukum)

Europe's Mars Express captured the original version of this image of Candor Chasma, one small branch of the enormous Valles Marineris, with its High Resolution Stereo Camera. A stereoscopic image contains the necessary information to simulate an entirely different perspective, as above. You can see a number of different views of Candor Chasma here.

Lunokhod Style

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Image credit: NASA or Soviet Union

A post on the planetary society links to this very cool article. Many of my generation may have assumed that the dinky little Pathfinder rover was the first remote vehicle to wander the surface of another world - but in fact the Soviets got there first.

The USSR placed two rovers, or Lunokhods on the surface of Earth's moon early in the seventies. It was also revealed in the 1990s that they even landed a pair of ill-fated rovers on Mars in the seventies - one of which expired after mere seconds, while the other was destroyed in what you might call a 'descent of unplanned rapidity' (or 'crash').

On the one hand, the lunokhods are very cool - not just a milestone in the history of space exploration, but a damn cool piece of retro chic. On the other hand, the Soviet Mars rovers are emblematic of the whole Soviet Mars program: cool ideas that failed spectacularly, seemingly through nothing but bad luck.

Victoria Crater

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Credit: NASA/JPL-Caltech/Cornell University

Here's a fraction of the most recent panorama from Opportunity, looking down into Victoria Crater. Though Opportunity - who recently celebrated her fourth Earth year on Mars - is the more physically healthy of the two rovers, it seems unlikely that she will ever re-emerge from the crater. Except, perhaps, as a museum piece...

Robotprints

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Credit: NASA/JPL-Caltech/Cornell University

I rather like this panorama from Opportunity, taken quite a few months ago, and uploaded to their website at the start of this year. There's a real sense of immediacy to this view of churned-up Martian soil and messy rocks.

Meanwhile, on Mars...

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Credit: NASA/JPL-Caltech/Cornell University

A shivering robot peers around at her surroundings.

Tiny Robo Tim

Credit: NASA/JPL-Caltech/Cornell
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Mars takes over twice as long to orbit the sun as the Earth, and its southern hemisphere is on the verge of winter. Poor dust-caked Spirit (compare the image above to this one) looked to be in dire straits with respect to its need for nourishing sunlight, however NASA have finally succeeded in perching it on a northern-facing slope so it can maximise its energy intake.

Also of interest, Mars will be in opposition, as viewed from the Earth, tomorrow on Christmas Eve.

Martian Potato Moons

Credit: NASA/JPL/JHUAPL
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Mars Reconnaissance Orbiter provides these two colour views of Mars' moons Phobos (above) and Deimos.

Phobos orbits Mars in a period shorter than a Martian day, so would appear to an observer on the surface to rise in the west and set in the east several times a day. Little Deimos is somewhat less interesting, but at least, unlike Phobos, it won't be smashing into its mother planet in about 100 million years.

Peering at Rocks

Credit: NASA/JPL-Caltech
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As it finished its second Martian year on Mars, NASA's Mars Exploration Rover Spirit was beginning to examine a group of angular rocks given informal names corresponding to peaks in the Colorado Rockies. A Martian year -- the amount of time it takes Mars to complete one orbit around the sun -- lasts for 687 Earth days. Spirit completed its second Martian year on the rover's 1,338th Martian day, or sol, corresponding to Oct. 8, 2007.

Exploring Mars on the most human scales yet: the Mars rovers are still going strong. NASA recently (hopefully not too optimistically) extended their mission into 2009.

You can read the Planetary Society's latest update on the rovers here.

What happened here?

Credit: NASA/JPL/University of Arizona
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From orbit, the latest addition to the robot party at the Red Planet, the Mars Reconnaissance Orbiter, gawps voyeuristically into Martian nooks and crannies with its powerful High Resolution Imaging Science Experiment (HiRISE) camera. Here it snaps a photo of a feature with the characteristics of water-carved channels, further evidence supporting a wet past for Mars.

Giant Flat Mountain from Orbit

Credit: NASA/JPL/Malin Space Science Systems
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Olympus Mons is a mountain of mystery. Taller than three Mount Everests and about as wide as the entire Hawaiian Island chain, this giant volcano is nearly as flat as a pancake. That is, its flanks typically only slope 2° to 5°.

Another image here from the late Mars Global Surveyor.

The Grandest Canyon

Credit: NASA/USGS
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From the Viking mission of the 1970s comes this staggering image of Valles Marineris: the largest canyon in the Solar System at over 3000 km long and up to 8 km deep.

The other notable canyon of immense size - that we know of - is, of course, Ithaca Chasma on Saturn's moon Tethys, at 2000km long and 3 to 5 km deep. Earth, by comparison, only sports a small crack of 446 km in length somewhere on its northern hemisphere.