Opinion: The Mystery of Triton's Origin
"Space scientists want to send a mission to Neptune and beyond. But they need a better plan than the one they've come up with"
Technology Review Feed - arXiv blog Download time: Jun 6 2011 8:47 AM ET
One of the puzzles over Neptune's moon Triton is its retrograde orbit: it moves in the opposite direction to the mother planet's rotation.
Many of the small outer moons of Jupiter, Saturn and Uranus also have retrograde orbits, almost certainly because they are captured objects.
But Triton is different. It is the seventh largest moon in the Solar System, bigger even than Pluto. So explaining its origin is not as simple as saying it must be a rock that flew too close. And yet that's what many planetary geologists believe.…