Is there life on Mars?
Landing area for Mars Phoenix probe (courtesy of NASA)
Missions to Mars have proved one of the trickier tasks in space exploration. To date, only 45% of probes we’ve sent to the red planet have arrived in one piece. Remember Beagle 2 with its Blur-composed call sign and Damien Hirst colour scheme? What might future Martians make of it as they try to piece together those multicoloured dots presumably now scattered around the landing site?
Beagle 2 wasn’t alone. In 1999 the Americans lost the Climate Orbiter and then the Mars Polar Lander. In future Johnny Mackintosh books I expect to reveal the real reason why some of the probes haven’t made it. NASA were so concerned that their 2001 Mars Surveyor Lander was cancelled as a result of previous failures but, like its classical namesake rising from the flames, the spacecraft was eventually taken out of mothballs and reborn as the Phoenix probe.
After a 423 million mile journey, Phoenix should land just after midnight on Sunday 26 May (British Summer Time). Unlike Beagle 2, which tried to cushion its impact with airbags, Phoenix fires true sci-fi style retro rockets, the last stage in slowing its speed down to only 5 mph. Right now, relative to us, the probe has reached 74,000 mph, but will hit the Martian atmosphere at only 14,000 mph because, in space travel, all speeds are relative (except the speed of light).
Phoenix reminds me of the Viking probes, two of which landed on Mars in the 1970s. The excitement of seeing the photos of the surface of another world, being slowly built up, was dissipated somewhat by the frustration of not being able to move around. Following on from the success of little Pathfinder, the rovers Spirit and Opportunity have been traversing the Martian surface for more than four years. It’s a sign of how far we’ve come that we’ll communicate with Phoenix via several of our spaceships now in orbit around the red planet, but it seems a shame that this new probe stays where it happens to land, especially now the technology has been proven.
Phoenix’s mission is to continue the search for water and also organic chemicals. For the organics, it repeats Viking’s methodology of digging up samples and putting them into a mass spectrometer, though the tools are nowadays much improved. For the water it has a decent digger to excavate a trench – the mission team says it doesn’t need to move around as we know where the Martian permafrost is. Let’s hope they’re right and the Phoenix doesn’t end up getting stuck on a rock.
For centuries people have speculated about finding life on Mars. Many think that finding it would be one of the greatest discoveries ever. However, Nick Bostrom, the Oxford-based futurist, hopes for humanity’s sake that there is no evidence. His argument is all tied up with something called the Fermi Paradox and wondering why we haven’t yet met ET.
Although Phoenix will look indirectly for signs of past life, its main purpose is to test out whether the red planet would be habitable for humans. For that we will need accessible water – we know liquid water once ran over the Martian surface. Now we want to see if there’s enough locked up in the polar ice caps for us to be able to colonize our neighbour.