science writing

Now wash your wheels!

Clandestine agents and heroic citizens of blockbuster sci-fi movies are often portrayed as defending the Earth from the alien miscreants of the Universe. Blasting slimy green extraterrestrials might be great cinema, but it doesn’t always represent the shrewdest of scientific moves. That’s because whilst the chances of ne’er-do-well space-faring aliens wandering around our towns and cities can be safely relegated to science-fiction, the reality is that it’s the Universe, not us, that needs defending from visitors from Earth.

So how do we clean our spacecraft when we send them out into space? To answer that question here’s the result of an interview I did with NASA’s Planetary Protection Officer a few months ago. This concern is particularly relevant given the current mission of NASA’s Phoenix Mars lander and that of the Mars Exploration Rovers, who are studying locales on the Red Planet that might be hospitable to life.

Ever since the first robotic missions to the planets we’ve also been inadvertently sending small amounts of microbes up there too. It wasn’t until the last few decades (when we began scouting for microbial life elsewhere in the Solar System) that this started to become a major headache for space agencies around the globe. The last thing we want to do in our search for life in the Solar System is discover the disastrously familiar sign of life which has piggybacked its way millions of kilometres from Earth.

Spirit & Opportunity were only allowed to take a certain level of spores with them. Courtesy: NASA/JPL/Caltech.

Today the responsibility for keeping NASA’s spacecraft clean (and in some ways protecting any alien life in the Solar System) falls on its Planetary Protection Officer Dr Catharine Conley. Her job is to see that NASA spacecraft are kept free from microbes from Earth that might be spread into space by our space-faring endeavours…well almost. It might surprise you that already we’ve let countless microbial ‘spores’ into the Cosmos. “There were probably viable spores on spacecraft that were launched over the past few decades, however we are quite careful to monitor the trajectories and subsequent disposition of the spacecraft, so that we know what has happened to them,” says Dr Conley.

The reason these microbes got out is that it’s not yet possible to completely sterilise a spacecraft before an interplanetary voyage. But all is not lost as Dr Conley explains. “From everything we have seen so far, it’s quite unlikely that any spores carried on those spacecraft have actually landed in a place where they might grow.”

So how exactly do you clean a spacecraft? If you’re now imagining a multi-million dollar probe being lathered in disinfectant by a group of fastidious sponge brandishing scientists, then you’re in for a shock. The reality is much more bizarre. “A variety of cleaning procedures are used, depending on the material requiring cleaning” explains Dr Conley. The aim is to make sure that the number of microbes on the spacecraft does not exceed pre-determined levels. Of all the methods used, the one that has thus far proved most effective is ‘dry heat’ sterilization. Put simply the spacecraft is baked in a giant oven at temperatures of several hundred degrees Celsius, killing most lurking micro-organisms.

Other methods such as swabbing exposed surface panels with alcohol are sometimes used and NASA is also developing other new methods to reduce the amount of potential microbial contaminants. One proposed method involves firing cold plasma at spacecraft, zapping any microbes. Another involves dousing any bacterial stowaways with hydrogen peroxide vapour. “The type of mission and the conditions we find at other planetary bodies are what dictates the level of protection,” explains Dr Conley. Yet, according to Dr Conley, in this article in NASA’s Astrobiology magazine these important protection regulations might generate complications when astronauts want to start exploring worlds like Mars; worlds which might harbour primitive life.

For the most part Mars’ surface is thought to be inhospitable to life, so astronauts will most likely be allowed to roam free over large areas of the barren ochre surface. But what if we actually want them to look at and explore the sites where living microbial life might be found?

That might not be so easy to do warns Dr Conley. “Humans will not be allowed to contaminate locations where Earth life might survive before we have a chance to study them sufficiently for signs of extraterrestrial life,” a proposition that is as reasonable as it is frustrating. If life is present on the red planet then it looks like it will be the electronic eyes of a rover, a wheeled robotic ambassador, which will glimpse the first signs of it. With the future of whole worlds at stake then, scientists can’t risk forgetting to wash their rovers’ wheels.

Book news (Part II)

Today I began work on the final chapter of the book. It’ll probably take about 4 weeks of writing to complete as I’ve also got to write the captions for the images too – but the point is that I am nearly finished! The chapter I’m currently working on isn’t actually the last chapter, it’s an earlier one. It’s also one of my favourite subjects so that should make this last bit quite fun to write. I’ll keep the blog updated with how it’s going but if I don’t post for a while you’ll know what I’m doing!

The Carnival of Space no. 49

Hello and welcome to the 49th Carnival of Space. I’m really pleased to be hosting the carnival this week as we have some brilliant stories for you, thanks to some great writers and bloggers. This is where after a week of hard work you can now sit back and get your full dose of astronomy related news and views, finding out what the blogosphere has had to say about the Universe, in the last week. Don’t forget to check back soon and subscribe to the RSS feed on the right to keep up-to-date with the site. So, without further delay let’s begin…

The start of this week’s carnival takes on a distinctly stellar theme. Fraser at Universe Today responds to a superb astronomical question from his young daughter that I am sure we have all wondered about at one point or another.

Towards the end of March a massive Gamma Ray Burst (or GRB) was seen in the night sky. It was the brightest most distant GRB to date and one that was so bright it was visible to the naked eye! Dr. Ian O’Neill on Astroengine asks whether a peculiar type of star called a ‘Wolf-Rayet star’ could be responsible.

Complementing this nicely, Ethan at Starts With A Bang! poses the question “Do all stars eventually explode?”. The Hubble Space Telescope has certainly found a star that will eventually explode. In fact, as Phil on the Bad Astronomy blog says, Hubble astronomers have caught a supernova in a galaxy right at the point it is beginning to ‘go off’.
If a star is big enough when it dies it can form a black hole. Alan Boyle, of Cosmic Log, explores how new simulations of black hole interactions are showing the disparity between Newton’s and Einstein’s gravitational theories.

With the release of the new Indiana Jones film a matter of months away, Rob carries out his own astronomy related archaeological investigation of a prehistoric site in Alabama in the USA, over at Orbiting Frog. Though as far as I can tell didn’t find any rats, sacred relics or hidden treasure!

Meanwhile Chris Lintott reports from the Royal Astronomical Society’s National Astronomy Meeting (on the NAM blog) on the discussion held in Belfast on the current funding situation of UK astronomy and particle physics.

One of the big tasks for those returning to the Moon and then looking forward to Mars is how we are going to carry out day-to-day tasks, like exercise and growing plants for food etc. Ken Murphy at Out of the Cradle explores how we might be able to grow plants in the lunar soil in part one of his post ‘Of a garden on the Moon’. Let’s hope when we get to the Moon or Mars they also have Internet access.

For those of you that can’t get enough of Mars though the Martian Chronicles team have another update on the Opportunity Mars Exploration Rover, including a stunning panorama of the martian ‘Cape Verde’ rocky outcrop. When we do get to Mars maybe we will move our bases around with giant robots, Colony Worlds investigates what that might involve. And if you are new to the excitement of martian exploration then Stuart has some tips on how to survive your first Mars landing. Meanwhile, Bill Dunford at ridingwithrobots.org has an incredible animation of Victoria crater taken at different times (and illuminations) during a martian day.

Centauri Dreams skeptically ponders whether the SETI program should search for extraterrestrial constructions known as Dyson Spheres, and asks if any other potential civilizations around other stars think like we do. Clearly when we humans want to venture out into space we are going to have to develop new technologies. Next Big Future has an article on how carbon nanotubes may be used in future space power and propulsion system whilst Henry Cate reports from Space Access 2008.

Music of the Spheres blogs about the 2008 Space Expo at the New England Air Museum. Even though the Space Shuttle simulated flights made by visitors to his stand might not have had the smoothest landings that NASA has seen, their educational value was worth it all.

A Mars Odyssey also brings us up-to-date on the launch of the Soyuz from Baikonur on the latest ISS Expedition 17.

Well that’s about it for this week’s Carnival of Space, remember that you can find a list of all previous carnivals on the Universe Today website.

Top: Artist’s impression of a GRB. Credit: NASA
Middle: Hubble has spied an exploding star in this galaxy (NGC 2397). Credit: NASA, ESA & Stephen Smartt (Queen’s University Belfast, UK)
Lower middle: Artist’s impression of a MER. Credit: NASA/JPL
Bottom: Touchdown for the Shuttle. Credit: NASA

Exoplanet NAM post

I’ve written up a new post about today’s NAM announcement of the discovery of an embryonic exoplanet. The first paragraph is below:

“Astronomers here in Belfast have just announced that they have discovered what they believe to be the youngest ever planet observed. So young that it may have not completely formed yet. They used radio telescopes in the UK (the MERLIN network) and in the US (the VLA) to study the star system of HL Tau, a star in Taurus about 520 light years from Earth”

You can read the full article and see the pictures here.

NAM day two

Well today is day two of the National Astronomy Meeting. I’m going to be posting any future NAM news I have on the NAMblog so be sure to check there for the latest NAM news. Today has kicked off with some great plenary session lectures on the acceleration of the Universe and the dynamic nature of the magnetic fields on the surface of the Sun. Chris and I have posted two takes on Dr Brian Schmidt’s ‘Measuring cosmic acceleration’ talk, why not take a look.

NAM news 2: Massive starburst in the early Universe

Dr. Scott Chapman from the Institute of Astronomy in Cambridge has just presented the latest results from a collaboration between the MERLIN UK radio telescope array, Keck (at optical wavelengths), the VLA in the US and the Plateau de Bure submillimetre observatory in France. The results show that there was a group of galaxies in the early Universe that experienced an incredible burst of star formation about 2 billion years after the Big Bang. This phenomenal burst of activity was observed in galaxies that were shining a mere 3 billion years after the Big Bang and is thought to have been vastly more dramatic than any star formation we see nowadays.

Remarkably it was only until relatively recently that astronomers detected a similar gathering of sub-mm galaxies in the early Universe. These galaxies are particularly faint in optical wavelengths but very bright in the radio wavelengths. Instruments like SCUBA mounted on the James Clerk Maxwell Telescope (JCMT), on Mauna Kea in Hawaii could see the sky in sub-mm wavelengths and so could detect them; allowing astronomers to investigate their nature. Yet astronomers believed that these galaxies were only part of what was going on (star-forming wise) in the early Universe, because SCUBA was good at looking at relatively cooler sub-mm galaxies.

Now, these new results from the collaboration of many telescopes do indeed show a gathering of slightly warmer galaxies, not altogether different from those spied by SCUBA, undergoing dramatic star formation. The observations indicate that these galaxies are surrounded by vast clouds of gas. That gas, the astronomers argue, will keep the star formation going at a tremendous rate for “hundreds of millions of years”.

You can see images from the results and a very cool video here.

NAM news 1: SuperWASP strikes (10x)

swasp_3.jpgOne of the results that has just been released from the National Astronomy Meeting is that the SuperWASP exoplanet hunting project has discovered an incredible 10 new exoplanets. SuperWASP is an ingenious project which uses eight sensitive CCDs on eight wide field telescopes to monitor a huge number of stars in the night sky. It can record an incredible 100,000 stars in one image! What they are looking for is the tell-tale blink (more of a temporary and gradual dimming) of a star’s light which indicates a planet passing in front of the star.

This method of looking for the dimming of a star is known as the ‘transit method’ of exoplanet hunting. There have been around 270 exoplanets discovered so far and 45 of those found have been via the transit method. What’s even more impressive is that of those 45, 15 were detected by the SuperWASP instruments. The new planets that the robotic telescope has discovered range in masses of between half and just over eight Jupiter masses.

If you haven’t heard of the SuperWASP project or want to find out more then have a read of their pages here.

Above: The SuperWASP-South instrument array
Credit: SuperWASP

Hubble finds methane on an exoplanet

The Hubble Space Telescope has recently found the organic molecule methane on the extrasolar planet HD 189733b. Here’s a section of the ESA press release below.

“Under the right circumstances methane can play a key role in prebiotic chemistry – the chemical reactions considered necessary to form life as we know it. Although methane has been detected on most of the planets in our Solar System, this is the first time any organic molecule has been detected on a world orbiting another star”

With an atmospheric temperature of around 900 degrees there certainly isn’t going to be life (at least as we know it) on HD 189733b. The importance of this observation is more that it is “proof that spectroscopy can eventually be done on a cooler and potentially habitable Earth-sized planet orbiting a dimmer red dwarf-type star” says Mark Swain who led the team that made the discovery at NASA’s Jet Propulsion Laboratory (JPL).

I saw this exciting news come in when I was working with the Hubble group in Germany and I began scripting a Hubblecast to cover the result. To see the finished piece visit the ESA Hubblecast no.14 page here.

Above: An artist’s impression of HD 189733b around its parent star.
Credit: Credit: ESA, NASA and G. Tinetti (University College London, UK & ESA)

Britain’s Moon shot

I have a new feature article (my first cover feature!) in April’s issue of BBC Sky At Night magazine, which is in the shops on Tuesday 18th March.

fc_large.jpgThe article covers the proposed MoonLITE probe, a UK mission to send a small spacecraft to the Moon deploying four missiles to study the lunar surface. The missiles (or ‘penetrators’ as they are actually called) will impact the surface and remain there working for about a year. They will create a seismometer network as well as carry out geological and chemical analyses of the lunar surface. It’s a fascinating proposal. You can get the full story and read several expert interviews in the article.

You shouldn’t fail to miss the cover in the shops, the graphic designers and illustrators who worked on this article have really brought the story to life. So if you do spot the magazine grab a copy and find out how the UK may soon be joining the return to the Moon!

N.b. If you are in south-east England on Wednesday (19th March), at 10:30am, tune into BBC Radio Kent as I will be speaking live with Dominic King about MoonLITE. If you are in or around Cumbria I will be talking live to Ian Timms about the mission on BBC Radio Cumbria at 12:40pm the same day.