For those who have not heard the news already, or who have forgotten, today is the day when the Rosette probe will make contact with comet 67P/Churyumov-Gerasimenko after a ten year journey, and begin collecting data and transmitting it back to Earth.

Rosetta was built by the European Space Agency, and launched back in 2004 aboard the Ariane 5 rocket as part of the ESA Horizon program. It is composed of both an orbiter and a lander, with a combined total of 21 sensors and probes which will be used on the comet. If successful, it will be the first detailed study of a comet, and should provide astronomers and astrophysicists with a wealth of new information.

But Rosetta has already done far more than its intended comet studies. In February 2007 it did a flyby of Mars and returned some interesting images of the red planet. Then in 2008 and 2010 it did flybys of two asteroids, returning data on them as well, before being placed into a near three year long hibernation while it traveled past Jupiter and out to comet 67P.

Back in January it was woken up again, and since then it has maneuvered close to the comet. Sometime tonight or tomorrow it will enter orbit around the nucleus of the comet, and once a suitable landing site has been found it will deploy the Philae lander to the surface (this is expected to happen sometime around November). The lander is expected to harpoon the surface and then drill itself in so that it can ride the comet nucleus for the next few months.

If both processes work as expected, then the Rosetta orbiter and the Philae lander will stay with the comet for the following year as it travels into the inner solar system and loops around the Sun. It will be interesting to see how the comet nucleus and tail will act in the solar winds as the heat from the Sun melts the surface of the comet. It has been a long journey for the probe, but it has already accomplished a lot. And with any luck, the next eighteen months of its adventure will be even more amazing!

More details as well as video of the landing can be viewed here.