[domdugg (OP)]

Philae and Rosetta are travelling with Comet 67P

Where will they go to? The Ort Cloud?
Will they ever come back? When?
How fast are they moving?
Will they go further and faster than Pioneer and Voyager?
Could we hitch a ride on comets for deepspace exploration?

[chris]

They'll go where the comet goes, although Rosetta won't look quite like it does at the moment, because it will be crash-landed into 67P later this year:

http://www.thenakedscientists.com/HTML/interviews/interview/1001662/

Chris

[evan_au]

Philae and Rosetta are travelling with Comet 67P

This comet does not approach the Sun quite as closely as the Earth.
* Perihelion = 1.2 Astronomical Units (AU). ie 20% farther out than the Earth

This comet travels a lot farther from the Sun than the Earth:
* Aphelion = 5.7  Astronomical Units (AU). ie nearly 6 times farther out than the Earth
* The Oort Cloud starts at about 1,000 AU, so the comet goes nowhere near this.

The orbit is 6.4 years, so they follow the same elliptical orbit every 6.4 years.

The velocity of the spacecraft is much lower than Voyager and Pioneer (or New Horizons), because it does not need to get out of the Solar System.

See: http://en.wikipedia.org/wiki/67P/Churyumov%E2%80%93Gerasimenko

Philae has been given up "for dead". Rosetta could continue observing the comet while the scientists think it is still bringing back useful data, but its solar panels produce much less power when the comet is far from the Sun.