The new results from astronomers using two telescopes on Hawaii – NASA’s Infrared Telescope Facility and the giant Keck telescope – which reveal the presence of methane in the atmosphere of Mars are enormously exciting. As far as we know, methane signals the presence of one of two things – either life or, more likely I would say, substantial geological activity on the surface. The volatile molecule will break down in the atmosphere, so for it to exist in detectable quantities it must be being replenished by one means or the other.
The press release makes no mention of the results from ESA’s Mars Express which also found methane in Mars’ atmosphere, announced a few years ago. The results of the Mars Express team were published in Science, the same journal that will carry the new results.
From what I can gather, the new results are an important confirmation of the Mars Express data, and move our understanding of what’s going on a step further forward. But not to mention that an ESA spacecraft had got there first is certainly uncharitable, and verges on the misleading (and why didn’t journalists check the story by googling ‘methane +mars’, for example?).
There used to be an old and hoary joke doing the rounds about how many times water had been discovered on Mars. Let’s not do the same with methane, potentially the most exciting discovery on the red planet for quite some time.
P.S. As ever Emily at the Planetary Society has all the details, including what exactly is new (seasonal variation) and how this fits with other work.
Remember Phoenix’s discovery of snow on Mars?. In the last public talk of the AAS conference yesterday, Principal Investigator Peter Smith updated those of us who normally think about galaxies rather than planets on Phoenix’s mission and the analysis that’s underway. There wasn’t too much new to say, but he did let slip that late in the mission they did detect falling ice not only high in the atmosphere, but actually reaching the ground.
So not only does it snow high up on Mars, but at least at the northerly latitude of Phoenix it hits the ground too. An amazing thought, isn’t it?
Last week’s Nature had a series of stories about the feature by Eric Hand. My reaction on reading it was a sense that he’d got it absolutely right, hitting a tone that is best described as qualified success.
There is no doubt that Phoenix was a success. It was a cheap (especially when compared to the next generation of Mars landers, the American MSL and European Exomars) spacecraft, and yet in landed and produced results from each of its instruments. The headlines were taken by the chemistry of the soil – perfect for growing asparagus, if only it weren’t sprinkled with oxidising perchlorates – but there were other, ground-breaking results too. Flying an atomic force microscope to another planet and getting it to work is breathtaking, for example, and I’m sure we’ll be surprised again and again as the teams publish their results.
And yet, and yet…Phoenix was beset with problems. The team did manage to get icy soil into Phoenix’s ovens, but never a pure sample of ice. As a result, what was for me the most important single result expected from the mission – a measurement which would have told us whether the ice that Phoenix was sitting on had melted recently or whether it had been frozen in place for billions, not millions of years – will never come. According to the article, there are hints in the data that might be the signature of organic materials, but as the team ran out of time to run their blank, comparison sample we will probably never know for sure.
The fact that these problems were avoidable – the Nature article mentions that the problems with TEGA could have, should have been spotted before launch – is ultimately irrelevant. All problems with spacecraft should probably have been foreseen and corrected, but 100% success is achievable only in the dreams of bureaucrats. What matters is the overwhelming need for the mission to be seen, and talked about, as a resounding success and nothing but that. What Phoenix was trying to do was hard, it put in a huge amount of work in a very nasty environment and we know more about Mars than we did. We shouldn’t be afraid to admit that it didn’t quite deliver everything it could have.
Where does this fear come from? It’s pervasive, and it’s not necessarily NASA’s fault. I know that when reporting on Phoenix my instinct was to tell the positive story, and I felt guilty for mentioning the problems that the team – some of the nicest people I’ve met in the five years I’ve been doing Sky at Night – were having.
In an accompanying editorial, Nature have an answer. They point out that because even cheap missions are rare and (compared to, say, funding an Earth-based research project or experiment) expensive, the cost of failure is too large. A single mishap can derail a program for years. Their solution is for there to be more recycling of material between missions – shared landing systems, for example.
The amazing rovers, Spirit and Opportunity, they point out, bounced to the surface in an airbag, whereas Phoenix touched down, and MSL, the next in line, will land via something very scary called a sky crane. (If you haven’t seen it, it’s found it’s way onto youtube).
Why didn’t all the missions use the same technology? What Nature is missing is that they couldn’t have done; if I understand the situation correctly, the trajectory needed to land Phoenix in the martian arctic wouldn’t have slowed the lander enough in the atmosphere to allow airbags to be used, and MSL is simply too heavy for airbags to support it. The spirit of their call is right, though – more probes, costing less (and therefore each individual mission doing less) and a more honest approach to success or failure is exactly what’s needed. And not just on Mars, either.
It turns out that it’s hard to launch a new shiny website while traveling through four airports and three countries in the space of less than 15 hours. With apologies to my talented co-presenter, Douglas Pierce-Price from ESO, I’m going to post our latest Living Space here.
In today’s show, Chris and Douglas talked about the American Astronomical Society meeting in St Louis, Missouri (where Chris had just heard the reports of the lowest mass exoplanet discovered so far – a three Earth-mass frozen planet orbiting a brown dwarf), the latest news from the Phoenix lander currently on the surface of Mars, and how a stroke of luck let astronomers catch a supernova in the act. They also celebrated the 10th anniversary of the First Light of the Very Large Telescope (VLT).
Phoenix lander starts work on Mars
The Phoenix lander has successfully landed in the northern polar region of Mars, on its mission to search for ice, study the history of water in the Martian arctic, and look for a habitable zone where life might have arisen. We admired the images from the Mars Reconnaissance Orbiter, showing Phoenix on its descent, and sitting safely on the Martian surface.
The lander is now beginning its work, and one of the first things it did was to use its robotic arm camera to look underneath itself. This revealed what appears to be ice, a few centimetres under the surface, uncovered by the blast from the descent thrusters. Phoenix is in a flat, frozen region of the planet, where polygonal patterns can be seen on the surface. These polygons are probably caused by cracks from the repeated shrinking and expansion of permafrost ice, and similar effects can be seen on Earth. The troughs around the polygons could be a good place for Phoenix to dig and study the Martian soil.
The mission scientists have a limited amount of time to do their work and get their results: once the Martian winter night arrives in a few months, Phoenix will not be able to use its solar cells for power, and it is not expected to survive the cold and ice. Before then, though, we look forward to lots of exciting results from Mars!
When a sufficiently massive star reaches the end of its life and runs out of nuclear fuel to burn, its core can collapse. This collapsing core then rebounds, and the shockwave blasts the star’s outer layers apart in a powerful explosion known as a supernova. We normally only detect supernovae when their visible light starts to increase, days after the shockwave. Theoretical models suggest that the initial blast itself should be accompanied by a flash of X-rays lasting a few minutes. However, such a short flash is hard to detect unless one is looking in the right direction at the right time. You’d have to have amazing luck to catch one.
That’s exactly what happened to a team led by Alicia Soderberg, who were using the X-ray telescope on the satellite Swift to study an existing supernova in the galaxy NGC 2770. Suddenly, they discovered a bright, completely new source of X-rays in the galaxy. Ground-based observatories quickly mobilised to study the event, which was confirmed to be a supernova caused by the core collapse of a massive star. This is the first time that a supernova has been caught in the act like this, and the observations will provide a treasure trove of information about these incredible explosions.
Tenth anniversary of First Light at the Very Large Telescope
ESO’s Very Large Telescope (VLT) is celebrating the tenth anniversary of its “First Light”. The telescope’s First Light occurred during the night of 25-26 May 1998, and the first images were released on 27 May 1998. The VLT, on Cerro Paranal in Chile, is the world’s most advanced optical/infrared observatory, with four giant 8.2-metre diameter “Unit Telescopes” and four 1.8-metre diameter movable “Auxiliary Telescopes”, which can be combined together into the “VLT Interferometer” for improved resolution.
One of the First Light images was of the giant star Eta Carinae and its surrounding cloud of dust and gas, which was taken with a test “guide camera”. Now, to mark the anniversary, two new images have been released, including a new one of Eta Carinae, this time taken with the advanced Adaptive Optics instrument NACO. Thanks to the power of Adaptive Optics, which corrects for the distorting effects of the Earth’s atmosphere as though the telescope were up in space, the new image has six or seven times better resolution and reveals even more details.
Over the last decade, the VLT has been responsible for a series of fantastic scientific results, including observations of a star orbiting extremely close to the supermassive black hole in the centre of our Milky Way Galaxy. This is, of course, just the beginning. With the second generation of advanced instruments for the VLT on its way, astronomers can look forward to the next decade of exciting discoveries.
As we’ve gone through the sessions here about Astronomy and New Media (aka the internet), the example I keep returning to (apart from Galaxy Zoo) is Phoenix’s use of the internet. The way they’ve distributed images and talked to the public has been exemplary, and the most fun example of this is their use of twitter.
Here’s a sample response which made be laugh, mentioned in the New York Times today :
“Wow, @MarsPhoenix must be really bored. He posts, like, all the time!”
This month’s Guide to the Night Sky is up over at the Times. I found myself getting increasingly interested in the topic of noctilucent (‘night shining’ clouds), so here’s the image of one made by the exhaust of the rocket that carried Phoenix to Mars.
It seems macabre to be thinking about the end of Phoenix‘s mission when it’s only just landed, but the odds are that the lander will fail to survive the Martian winter. In the Martian Arctic circle, Phoenix will not see the sun set until it’s September here on Earth, but the nights will get longer and longer until the lander eventually endures a hundred or so sols (Martian days) of consecutive darkness. It’s not expected to come out of the other end of this ordeal, but if it does it’s been programmed with a ‘Lazarus’ mode, calling home to Earth to let us know it’s back from the dead.
I was reminded of this when reviewing the UK newspaper coverage of the landing today. Top marks go to the Independent which splashed images from Phoenix across its front page and included a supportive leading article, but I was amused by a slip in the coverage by the Mail, the only other paper to include the news of Phoenix‘s safe landing on the cover.
They include a quote from Carl Sagan on the Planetary Society’s program to send a DVD with names to the surface. The Scotsman goes further, including Sagan referring to the landing taking place in 2008. As Sagan sadly died in 1996, this seems a bit of a stretch unless the Lazarus mode can bring more than Phoenix back from the dead.
Someone whose political prospects probably need resurrecting, the prime minister Gordon Brown, is probably already sick of Phoenix. The cartoonist in every paper I opened had had the same idea, depicting Phoenix discovering no trace of life in Brown’s prospects; here’s the Times’ variation on the theme.