Spacecraft returns from Mars (not quite)

Hi,

Comet bound probe Rosetta returns for a gravity slingshot on Tuesday.
So an almost Mars to Earth return (give or take a few thousand km)!

Time for another teaser. Could you name all the solar system bodies used to give a gravitational slingshot (for any mission)?

No prizes for the first correct answer (not even Sky-High 2008), except the sastisfaction of getting it right!

John

Well, off the top of my head, the Voyagers got Earth, Venus, Jupiter, Saturn, Uranus, and (slightly) Neptune.
Did some of the Mariners get Venus?
Galileo got Venus and Earth.
Moon for Apollos (and more).

The Sun in one of the Star Trek movies and I think a Stargate episode or two

Ok, I'm not sure if it's technically a gravity assist, but New Horizons will be directed on to a couple of Edgeworth-Kuiper Belt objects after the Pluto encounter in 2015.

Hope the Open University exam went well John!

John

Hi. Not wanting to sound like comic book guy but.....

There was no gravity assist for Neptune. When voyager two approached neptune the aim was to change its course so that it could fly past its giant moon Triton 5 hours later after closest approach and take pictures of it.

As Neptune's moon Triton orbits inclined to the ecliptic the only way for this to happen was to fly really close to the planet over its north pole and thus the trajectory of the craft was bent downwards enough to effect the flyby of Triton.

Thus Voyager picked up no extra speed from neptune. It just changed trajectory. (Worst gravity assist.......ever!!!!!)

DB

Thus Voyager picked up no extra speed from neptune. It just changed trajectory. (Worst gravity assist.......ever!!!!!)

I think it still counts. The velocity (speed in a given direction remember!) changed due to the mass of the planet.