NASA captures a new 3D view of Mars’s moon Phobos

NASA You’d think that Mars’s moon Phobos – a 13.5-mile wide lump of brownish rock full of craters – wouldn’t be the most interesting place in the Solar System to take photos. But then space exploration does tend to throw up a lot of surprises.

One of NASA’s Mars probes recently captured the above image, and it’s revealing some fascinating details about something most people probably didn’t even know existed.

The most obvious thing about Phobos is the huge crater on the bottom-right of the image. Scientists say that its slight bluish color means it hasn’t been exposed to space as long as the rest of the moon, meaning the impact that produced the crater could have been quite recent.

Wikipedia Phobos may also be home to water-ice and materials rich in carbon, which is why a Russian-Chinese mission to collect samples from Phobos is expected to launch next summer.

NASA’s Mars Reconnaissance Orbiter snapped the new shot of Phobos from 4000 miles away, so I’m pretty impressed that the detail’s so good. In the full size image each pixel represents 22 feet (6.8 meters), so you can zoom in quite a lot. (Click here to download the full-size image. Be warned! It’s a 20mb file, so if you’re still using ancient dial-up be prepared to wait a few hours.) It’s really cool zooming in on the thousands of craters dotting the moon, especially the ones on the edge of the Moon and on the day-night border.

Phobos and Deimos What else is so great about the new image? OK, several probes have imaged Phobos before, but because MRO took two photos you can actually see the photo in 3D if you’ve got some of those special glasses.

The image also shows landslides around the massive crater (Stickney crater), and you can see some craters in the dark region illuminated by Mars-shine. This is when light from the Sun reflects off Mars onto Phobos, and it happens with the Earth and our Moon too – take a look next time there’s a crescent Moon.

Above all, I just think it’s amazing that yet another bit our Universe is proving to be so interesting. Before I heard about this photo I just though Phobos was a boring old lump of rock, but as you can see it’s actually a pretty interesting corner of our Solar System after all.

Want to know more about the Red Planet? See the Solar System’s biggest volcano in 3D, see photos of the first ever avalanche captured on Mars, and read why radiation may prevent humans from ever visiting it.

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Radiation may prevent humans ever going to Mars

MSNBC / NASA

It’s amazing that the human race is now close to sending a person to another planet for the first time in the history of civilization – NASA hopes to put a man on Mars by 2030, or at least not too long after. But why will it take 20 years? Well, there are loads of problems scientists have to overcome like the psychological impacts of a 2-3 year Wikipedia / NASA trip, the problem of having enough food and water, and finding a fuel that would be powerful enough to power a heavy craft to Mars.

But there’s something perhaps even more important that people often overlook, and it’s something that could affect long-term missions to the Moon too – radiation from the Sun. It’s proving to be a huge stumbling block.

Our Sun constantly bombards our planet – and everywhere else in the Solar System – with a stream of assorted particles, many of which would be harmful to humans if we were exposed to them. In fact, these ‘cosmic rays’, as they’re sometimes also known, were the main thing that prevented life on Earth originating until a billion or so years after its creation. Only when a few resistant bacteria (and lots Wikipedia / NASA of volcanoes) started producing gases to produce an atmosphere could more advanced life develop.

Any mission to space obviously involves going outside our atmosphere, which means leaving the shield that protects us from solar radiation. Even with complex spacesuits, modern astronauts frequently see white flashes of light as solar particles interact with their eyes.

But if astronauts can cope with solar radiation now (for example on Shuttle missions and at the ISS), why wouldn’t they be able to cope on a Moon base or on Mars?

The problem is that unlike on the Shuttle or ISS, astronauts walking around on the Moon or Mars would have only their spacesuits to protect them. On a Moon base the astronauts would be exposed to radiation for days until they finished building the base, Wikipedia / NASA and on Mars the astronauts would want to spend several weeks exploring to make the 2-3 year journey worthwhile. All that radiation would build up, and could trigger things like cancer and tumors.

What’s the solution? It’s basically just a matter of trying to research better and better lightweight protection that can be used for spacesuits – but that could take many years yet. Let’s just hope it doesn’t take too long.

Check out my last post to find out what happens when solar radiation collides with our atmosphere: aurora. There’s a cool image of aurora from space.

Discovered on Mars: Salt that could pinpoint location of life

NASA / Wikipedia Whenever I’m putting salt on my food I don’t usually start me thinking about life on Mars. To be honest, I’d be a bit worried if anyone started thinking about extraterrestrial life instead of enjoying their nice meal (especially if it was while having a romantic dinner out).

 Hmm… what’s this got to do with science? A NASA probe (Mars Odyssey) has just discovered an area of salt deposits on the Red Planet. Although NASA / Wikipediasalt isn’t usually something you’d associate with life, it is in fact a huge clue as to where ancient Martian life may once have lived.

It’s all down to the fact that whenever water flows over rocks, it erodes them, absorbing some of the minerals contained in the rocks. Among these minerals is sodium chloride – or common salt – and its discovery on Mars could be pivotal in deciding where we go next to look for life on Mars.

In all the places where there are salt deposits we can be pretty sure that water once flowed there. Add to water the warmer temperatures that Mars had when the newly discovered salt deposits were found (they formed 3.5 to 3.9 billion years ago) and you get conditions quite favorable to life. Whether life actually existed or not remains to be seen, but knowing where liquid water once flowed makes the task of searching for life much easier.

CNN / NASAWhile I’m writing about Mars, here’s some disturbing news: NASA has just announced it is cutting funding to the amazing Spirit and Opportunity probes by 20%. As you can see by clicking here and here, these two rovers have been among the best ever sent to Mars, so it’s worrying that NASA isn’t willing to pay enough for them. It’s a shame that George Bush doesn’t realize that when he says he wants a man on Mars by 2030, he doesn’t realize that it won’t be free.

Check out the biggest volcano in the Solar System (on Mars) in 3D here, and read about the water-formed gullies recently discovered on the Red Planet here.

Melting snow made water flow on Mars

National Geographic

In the search for life, Mars has been a bit of a let-down so far. A few decades ago everyone thought there were canals there built by little green men. It turned out that Mars’s surface features had just been misinterpreted. Then there was that famous rock half-way through the last decade that was thought to contain bacteria – it was actually a weird-shaped mineral. Then a few months ago we were told water had been seen flowing on Mars… only to discover that it was dust, not water. Oops.

But now a new discovery has raised the possibility of life existing on Mars, even if it died out long ago. Scientists have concluded that several gullies created millions of years ago were almost certainly formed by flowing water. Where did the water come from? Probably from melting snow, which started to thaw as the Martian spring began.

National GeographicLike any planet, the angle of Mars’s axis of rotation varies gradually over long periods of time. In fact, it may have reached as much as 45 degrees or more several million years ago, double its current angle of around 23 degrees. This would mean that it had more extreme seasons, which could have contributed to the thawing of the ice. Another intriguing possibility is that water somehow burst out from underground springs.

It’s all very well saying water was flowing millions of years ago, but how do we know? Basically, scientists saw that the gullies all tended to point in the same direction, which would tie in with the idea that the gullies were something to do with the Sun melting ice. The Sun would be at the same angle each spring, causing snow to melt in the same locations, carving out these gullies.

Does this latest discovery have any big implications for the hunt for life? It does raise the chances that there was once life on Mars, although it was already quite well known that Mars used to be a wetter planet. Nevertheless, every step forward in the search for life is important, and I’m hoping that this discovery will be able to pinpoint scientists to the locations where life was most likely to have existed.

Avalanche on Mars: NASA releases stunning images

What happens when you disturb some ice at the top of a cliff that’s half a mile tall? Check out this image for the answer:

The first Martian avalanche ever photographed | Image: NASA

And that cloud of dust in the image above isn’t just any old avalanche – it’s an avalanche on Mars! As if that wasn’t spectacular enough, there were actually four avalanches in total, all captured in the same image (click here).

So what’s in that billowing red cloud? It’s almost all a mixture of frozen carbon dioxide and Martian dust, although there may have been some huge chunks of rock in there too. If a human was standing at the bottom, chances are they’d have been completely swept away.

Talking about standing at the bottom, if you were in that unlucky position, you wouldn’t have had much time to run away because even though the cliff was over 2,300 feet high, its slopes descended at the incredibly sharp angle of angle of over 60 degrees.

Mars Reconnaissance Orbiter | Image: NASA The amazing thing about this image is that nearly every other image of Mars is static, because the Red Planet’s surface remains much the same for millions of years. To see this avalanche in progress required a huge amount of luck, especially as the probe that snapped it (NASA’s Mars Reconnaissance Orbiter) was investigating something unrelated at the time.

The big question puzzling NASA is working out why the avalanche happened. The main theory at the moment is that some of the ice melted, causing disturbances that triggered a massive avalanche – the image was taken in Martian spring, when the planet was starting to warm up after the winter.

But another interesting, though unlikely, theory is that a small asteroid crashed into the cliff, unleashing the cloud of dust and ice. Alternatively, there may have been an earthquake (sorry, Mars-quake).

Mars | Image: National GeographicWhatever caused it, this avalanche image is one of the most stunning things to come from Mars exploration in quite a while. I’m looking forward to the day when probes start having video capability – that would make stunning moments like this just extraordinary.

Mars in 3D for the first time

The new 3D view from Mars Express | Image: National Geographic / ESA We’ve seen Mars from an aerial view, we’ve seen it from the ground, but what about in 3D? Well now we can do that too, thanks to Europe’s Mars Express probe.

The 3D shot (right) of Olympus Mons, the biggest volcano or mountain anywhere in the Solar System, shows the topography of Mars in unprecedented detail. There are amazing possibilities for this kind of information when it is combined with aerial views, such as the one to the below.

But why do we want to know loads about the altitudes of different bits of Mars? Well, it could actually play a pivotal role in the search for life, because by analyzing the altitudes of hills and surface features, scientists are able to tell where water has once flowed. It is thought that life could only ever have existed where water was present.

An aerial view of Olympus Mons | Image: WikipediaAnother big question: how on Earth do you get 3D shots like this? The obvious first thought would be radar or lasers, which NASA has previously used on its Mars Global Surveyor mission. However, these only provide the height at the exact point under the probe.

To get detailed measurements over a wide area, Mars Express used a technique that involved taking three photos: one slightly before it was overhead Olympus Mons, one above it, and one slightly after it had flown over it. By combining these three different angles, scientists were able to construct a 3D image.

We’ve only just started our exploration of Mars; there are loads more probes set to explore the Red Planet before 2030, NASA’s target date for the First Man on Mars. It’s a pretty exciting time to be in for space exploration! The Mars Express probe | Image: ESA