Two weeks ago an amazing feat of space exploration took place. Comet 67P/Churyumar-Gerasimenko received its first visitor from earth, 514 million km away, in the shape of a washing
machine sized lander called Philae.
The European Space Agency seemed to deliver the impossible; getting a spacecraft to a comet 4km wide and travelling at a staggering 60,000km per hour, and then landing a tiny vessel on it. You can therefore appreciate the screams coming from those who have worked on the project when confirmation of Philae’s touchdown was received.
For some this represents decades of dedicated work to achieve this. After approval for the project in 1993, Rosetta launched on 2nd March 2004. Ten years later in August 2014 the spacecraft finally made its rendezvous with the comet.
Tension mounted until finally on 12th November the world watched as the go was given to launch Phillae from Rosetta, enabling it to make its last journey to the comet surface.
The livestream of the event lasted all day, although to be honest watching people watching computer screens made for pretty boring viewing. But it was impossible not to stay hooked. After all the closest we’ve come to landing on a comet up until now was watching Bruce Willis in the film Armageddon don a spacesuit, Liv Tyler crying a lot and singing ‘I don’t want to miss a thing’ at top of our voices.
In the end, the landing wasn’t perfect, but after all neither was the landing in Armageddon and that was a movie. But the important thing is that Philae did land. Well actually it landed three times, with the first seeing the lander bounce 1km off the surface before landing two hours later with a smaller bounce. Philae finally found itself on the side of a rocky cliff face, a kilometre away from the spot where it was designed to land.
So why all the fuss? Well you only have to look towards the meanings of Rosetta and Philae, named after the stone and the obelisk, which were used to decipher Egyptian hieroglyphics. The spacecraft and the lander are subsequently set to decipher the language of the solar system.
Phillae managed to perform its science and transfer its data to Rosetta before it batteries ran out of power. This data is still being analysed but we do have some early results. Scientists were surprised that hard ice lies only 10-20cm below the dust on the surface of the comet, whilst Philae bouncing actually helped with measurements of 67P’s magnetic field, which will help model planet formation.
But the biggest finding was that the surface of the comet contains organic molecules. This has raised the question of whether a comet was responsible for life on earth, delivering molecules such as amino acids and water. Hopefully further results will be able to reveal if this is true and move us one step closer to discovering the mysteries of the universe.
New comet missions are already in planning with this project due to finish in December 2015, although Rosetta could still transit data after this. The biggest question at the moment is whether Philae will gain enough solar energy during this time to wake up and perform more science. Only time will tell as 67P moves closer to the sun.
It is hard not to think of philae as having human qualities. This is helped by it having its own twitter feed @Philae2014, with its last tweet being “My #lifeonacomet has just begun @ESA_Rosetta. I’ll tell you more about my new home, comet #67P soon…zzzzz”.. Sleep well little lander, we hope to see you soon.