After a seven year voyage, the joint NASA/ESA/ISA Cassini spacecraft is nearing the point of releasing the European Space Agency’s Huygens probe to land on Titan, one of the moons of Saturn. Amongst other instruments, Huygens is carrying the Open University’s Surface Science Package (SSP), to investigate Titan. Whilst the Open University’s SSP team are busy preparing for the moment of touch down, they’ve still found time to run a team competition on exactly when Huygens will touch down, and open2.net  offered you the chance to take part too!

The question is – what time will Huygens land on Titan?
The competition has now closed; watch Stardate on Friday night to see how close your estimate was.

The Surface Science Package team is playing for a bottle of whisky, but we’ve managed to come up with something better! The open2.net winner will receive a fantastic amateur astronomical telescope with which you'll be able to observe Saturn, and to help you get the most from your telescope we’ll even throw in a year's subscription to an astronomy magazine.

You might wonder why the scientists don’t know when the probe will touch down – in fact they do, to a degree. The problem for them, and for you, is that there are a number of factors that can affect the time of touch down. So if you fancy winning this stellar prize you’ll need to get your thinking caps on! Click the "next" link to read an outline of the sequence of events, and the key factors that could affect the time of touch down.