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A Planet That Orbits Its Star the Wrong Way
Smivs writes "BBC News is reporting that astronomers have discovered the first planet that orbits in the opposite direction to the spin of its star. Planets form out of the same swirling gas cloud that creates a star, so they are expected to orbit in the same direction that the star rotates. The new planet is thought to have been flung into its 'retrograde' orbit by a close encounter with either another planet or with a passing star. The work has been submitted to the Astrophysical Journal for publication. Co-author Coel Hellier, from Keele University in Staffordshire, UK, said planets with retrograde orbits were thought to be rare. 'With everything [in the star system] swirling around the same way and the star spinning the same way, you have to do quite a lot to it to make it go in the opposite direction.' Professor Hellier said a near-collision was probably responsible for this planet's unusual orbit. 'If you have a near-collision, then you'll have a large gravitational slingshot from that interaction,' he explained. 'This is the likeliest explanation. But it might be possible you can do it by gradually perturbing the orbit through the influence of a second planet. So far, we haven't found any evidence of a second planet there.'"
Maybe the sun reversed its spin.
Doesn't everything rotate backwards if its from down under?
The sun is the same in a relative way, but you are shorter of breath and one day closer to death
All the other planets keep pointing and saying "You're doing it wrong!"
Anybody want my mod points?
A rouge planet
What does Mars have to do with this?
Er, no. The idea is that the inclination of the orbit keeps getting larger until the planet is orbiting "backwards." The planet doesn't stop and reverse its orbit.
Cheers,
Dave
They that can give up essential liberty to obtain a little temporary safety deserve neither safety nor liberty.
Ben
No. Here's the ASCII art.
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The World Wide Web is dying. Soon, we shall have only the Internet.
Well, in our solar system at least one planet is spinning the other way around: http://wiki.answers.com/Q/Why_does_venus_spin_the_other_way It's not quite the same like orbiting into the opposite direction, but the Venus apparently received a nudge or two as well in order to spin the other way around. Such accidents appear to happen.
To put this in analogy form:
Picture someone making a pizza, when they spin it and throw it up in the air it lands spinning the same way. But if the pizza flips over in mid-air the rotation will be reversed when it lands but it didn't have to stop and reverse direction to do it.
Oh, and somehow a car is involved.
I was looking at the stars one evening and the thought occurred to me that every star harbors a hideous mess; an immense collection of orbiting debris ranging from bloated gas giants with dozens of exotic moons to mangled chunks of gold weighing billions of tons. Those nice neat little points of light are actually solar systems, every bit as rich and complex as our own. Life, at least in primitive forms, is probably a common afterthought.
Think about the planet you're on now. Everything beyond iron is the shrapnel of stellar detonations coalesced and melted into a ball of metal orbiting the sun. Staggering quantities of baryons mushed together in weird configurations, colliding, erupting and aging for billions of years. Somewhere there is a near perfect sphere of nickel weighing five Earths and orbiting a black hole. It will be destroyed next week when it collides with and vanishes forever into the guts of an 9 billion year old brown dwarf. It will have never been observed by anything more sentient than a dusty comet.
When you really think about it the universe is creepy.
Extrasolar astronomy requires extraordinary equipment. We need to build more of it and figure out what the universe looks like below cosmological scales because we haven't got the first clue what's really out there. Humans were simply not endowed by nature with sufficient imagination to anticipate more than a small fraction of all the crazy shit we're going to find.