I'm not entirely sure - but I think - that what it is is that first, Rosetta was moving too fast to be gravitationally bound around the comet. So it has to lose speed relative to the comet to get into a lower orbit. So at first at least was not gravitationally bound to the comet, but using the rocket thrusts at each corner to keep it close to the comet as well as slowing its transverse velocity relative to the comet.
So, it could have done that by doing a steady very low level of thrust. But it worked better to do these triangular orbits that let it go close to the comet in the middle of each leg of the triangle.
Then the triangular orbit with thrusts also lets you have a different orbital period from a circular orbit. And the thrusts are low so don't use a lot of fuel.
But I'm just basing that on internet discussions such as
Is this really Rosetta's orbit around 67P?
for now. So don't rely on this too much and look forward to a more detailed and answer from someone. Also will see if I can find anything published.
Presumably there are research papers and such like somewhere that go into the techy details for this orbit.
See also: How does Rosetta stay in orbit around 67P if there is so little gravity?
So, it could have done that by doing a steady very low level of thrust. But it worked better to do these triangular orbits that let it go close to the comet in the middle of each leg of the triangle.
Then the triangular orbit with thrusts also lets you have a different orbital period from a circular orbit. And the thrusts are low so don't use a lot of fuel.
But I'm just basing that on internet discussions such as
Is this really Rosetta's orbit around 67P?
for now. So don't rely on this too much and look forward to a more detailed and answer from someone. Also will see if I can find anything published.
Presumably there are research papers and such like somewhere that go into the techy details for this orbit.
See also: How does Rosetta stay in orbit around 67P if there is so little gravity?
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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