A New Earth and the Missions to Mars
I realize I’m privileged to have access to some of the world’s cutting edge science, but last week was particularly special with a visit to University College London to hear a mixture of astrophysicists and astrobiologists talk to journalists about their cutting edge work,organized by the ABSW, the Association of British Science Writers, of which I’m a member.
Now we all know scientists can sometimes waffle, but this brave half-dozen weren’t allowed that luxury. The format for the talks was a pecha kucha – born in Japan, you have 20 slides, each lasting for exactly 20 seconds, to get your point across. That’s 6 minutes, 40 seconds (and not a second more) to say who you are, what you do and pitch for a place in the science columns of Britain’s newspapers.
First up, Giovanna Tinetti asked what exoplanets are actually made of. For those out of the loop, exoplanets are those orbiting other stars, far beyond out own solar system. We weren’t sure such things even existed until the 1990s, but nowadays there are more than 700 confirmed cases, with hundreds more candidates awaiting confirmation. recently some astronomers have gone so far as to sayy that every star in our galaxy must have planets orbiting.The most productive way to search for these faraway worlds is by using the Kepler Space Telescope. Looking back along a populous spiral arm of the Milky Way, this other Hubble is a study in concentration, staring fixedly at a single window on the stars, watching for the most minute variation in their light. And by analying this light – the chemical clues hidden within the spectra, scientists like Giovanna can tell what planets hundreds of light years away are made from. She’s looking for those that are habitable. Soon, New Earth need not be a thing of science fiction stories, especially if Giovanna’s plans for ECHO, the Exoplanet Characterisation Observatory, are approved by ESA (the European Space Agency).
Ofer Lahav, Professor of Astronomy at UCL, chose to talk about dark energy, the mysterious entity that apparently makes up three quarters of out universe, but which we didn’t even know was there until 1998. For me the most incredible, unexpected discovery of the last fifty years has been that the rate of expansion of the universe is increasing. No one expected this. Everyone wants to know why, but Ofer was impressively agnostic in his views. Either an entity we call dark energy permeates space itself, acting as Einsteins cosmological constant, or the best theories we have are very wrong. Once upon a time our best theory was Newton’s, but it couldn’t explain why Mercury orbited the Sun the way it did. Along came Einstein, General Relativity and a revolution in science. With the dark energy anomaly, are we on the cusp of another such paradigm shift?
Next, how would you rate a snowball’s chances in hell? According to Geraint Jones they turn out to be a lot worse than a comet grazing the edge of the Sun. In December (2011) Comet Lovejoy’s trajectory sent it plunging into the Sun’s corona. Now comets are pretty much snowballs and our star is one of the hottest things around. Because of that, few astrophysicists expected to see anything reappear on the other side, but that’s exactly what the plucky comet did.
Astrophysics moved to astrobiology and Peter Grindrod talked about the Mars Science Laboratory, otherwise known as Curiosity. Given that NASA’s superprobe is currently en route to Mars with my name and also Johnny and Clara Mackintosh’s recorded on its microchips, I rather thought I knew all I needed it about this mracle of interplanetary engineering. Not so. it turned out I was very light on where Curiosity is going and exactly why. The Gale Crater reveals strata twice the height of the Grand Canyon, a timescope through which to observe millions of years of Martian geology. We even got to look at the view using 3D glasses.
I’m sure Claire Cousins would like to go to Mars, but she’s looking for analogues of the Red Planet here on Earth. If we can find local places that are similar we can test our robotic Martian explorers and see close up how they perform. So, despite being based at Birkbeck and UCL she’s a frequent visitor to glaciers and volcanoes in Svalbard and Iceland. it’s a tough job, but someone has to be an astrobiologist. Claire’s working on the joint ESA/NASA ExoMars mission – I’m hoping that in a few years’ time might also carry Johnny Mackintosh to our near neighbour, where it will proceed to drill into the red soil, searching for the elusive evidence of life on another world.
So is there life on Mars? It’s no small affair to most of us and Lewis Dartnell continued the theme, talking about extremeophiles, the super bacteria that survive on Earth in places almost every bit as hostile as the Martian dunes – places such as the dry valleys in Antartica. Become an astrobiologist and, even if you don’t get to the stars you’ll certainly see some very cool places on Earth. You don’t imagine drought on the Earth’s southernmost outpost, but these valleys have less rainfall than the Sahara Desert. For a long while we assumed nothing lived there, but now we know better. Step forward, Conan the Bacterium! If such lifeforms can survive freezing temperatures and minute quantites of water here, surely we will soon find similar examples on Mars.
My mind buzzing it got better as Geraint, Peter, Claire and Lewis joined me down the pub to continue our other-worldly discussions, freed from the limitations of 6 minutes, 40 seconds of PowerPoint presentations.