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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.'"
You know, he has this thing about spinning planets the other way around...
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
British?
All the other planets keep pointing and saying "You're doing it wrong!"
Anybody want my mod points?
but wouldn't this type of retrograde orbit be possible if the planet had gone "rouge" from it's original system and was then captured in the gravity well of its current parent star?
"...you can do it by gradually perturbing the orbit through the influence of a second planet" claims the article.
But, if it were to happen slowly, doesn't that imply that at some point it has a minimal orbital speed (if that's the correct term), and would fall right in? Seems to me that if it reversed direction, it must have been a relatively quick event. Unless, perhaps, the planet ends up being sent away from the star, and is then recaptured in a retrograde orbit. But, that's still not a "gradual perturbation."
"National Security is the chief cause of national insecurity." - Celine's First Law
They're already working on that; I read something recently about a probe that they're testing on Earth right now (it's in space, looking at Earth as a control).
I think you mean the LCROSS Spacecraft
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.
planets with retrograde orbits were thought to be rare
Since this is the only one that's been found, I'd say that planets with retrograde orbits are still thought to be rare.
And the men who hold high places must be the ones who start
To mold a new reality... closer to the heart
You mean its an Australian planet, mate?
rewriting history since 2109
I would think that one side of the star would be blueshifted, the other side redshifted ever so slightly.
I also wonder if the planet suffers more collisions than it would otherwise.
However, we're still unable to detect Earth-size planets in other star systems, as most of the planets we've detected are Jupiter-sized or more, but they are detecting progressively smaller planets.
You're a bit behind on that. Planets that are well within one order of magnitude of the size of Earth have been discovered. This one may be less than twice the size of Earth.
How about a direct capture, from an near-encounter with another star? That is, similar to the explanation in TFA, except that the planet originally belonged to the other star.
Why does everything different have to be labeled 'wrong'?
Have gnu, will travel.
Instead of spinning the "wrong" way, couldn't the planet just have a 180 degree axial tilt, sort of like Uranus has a pretty steep 97 degree tilt. At 180 degrees, it would be right sight up by a different perspective, but spinning the opposite direction as the star.
Morphing Software
Not as apples to oranges as you think. Astronomical models are actually what inspired the model of the atom and some of the basic quantum theories.
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.
This evokes that scene from "Trains Planes and Automobiles"......
Tsukasa: All I really want, is to be left alone...
It already hasn't
Venus SPINS opposite of the rest of planets. It orbits in the same direction. Uranus' axis of rotation is rotated 90 degrees, so it lies nearly in the solar plane. But it orbits like the rest of the planets. Pluto has a retarded orbit (no, that's not a scientific term), but its still going in the same direction. You mixed up orbit and rotation.
It is probably not a planet. It is a Death Star. Lord Vader is near!
Nope. It would just take one swift hit normal to the plane of the ecliptic to cause the angle of inclination to steadily change until it was revolving backward. However, the inclination may still be changing for all I know.
Nope. Each swift hit (delta-momentum) results in a single orbit change. A hit normal to the ecliptic is the most efficient in terms of angle-of-inclination change, but it does not cause a continuing inclination change.
why do you slashfucks keep using this order of magnitude shit even when it doesn't apply? do you really think it makes you look smart? orders of magnitude are used in a very specific fashion that even a 2nd grader can understand but you guys keep throwing it out there like it's a generalization. it's fucking not.
What's wrong with what he said? He said planets within an order of magnitude have been found. That means planets up to ten times as massive as the earth or as small as on tenth of the earth. He then points to an example where the planet is estimated to be half the size of earth.
Maybe you should brush up on simple 2nd grade mathematics principles before taking a pitchfork out and lighting that flaming brand?
As for a generalization, it can very well be one. It compares like objects within a scale that doesn't require any other measurements. You can say that one object is 2 magnitudes bigger than another if it is 100 times the size. You don't need to measure either object in any units.
So either get used to us "slashfucks" using scientifically agreed to and mathematically correct statements even if you don't understand them, or well, feel free to go find a site more suited to your level. Perhaps something with lolcatz or photos and a rating system?
Moved to http://soylentnews.org/. You are invited to join us too!
Well, maybe you were amazed. The existence of extra-solar planets has never been in serious doubt; we went a long time without finding any for the simple reason that they are extremely hard to detect. There were many supposed observations that fizzled out in experimental error, and that resulted in a lot of skepticism being attached to further finds. Now that we have the proper measurement techniques, the discoveries are coming at a rate of a dozen or more per year.
Look at it this way. Suppose you and I are standing on two mountaintops a few miles apart on a dark moonless night. I have a five-cell flashlight and one of those war-surplus searchlights they use to advertise new furniture stores. If I point the flashlight at you and turn it on, you'll see it easily.
Now suppose I point the searchlight at you and turn it on. Then I turn the flashlight on again -- or maybe I don't. Can you tell whether it's on or not?
That is approximately the problem involved in finding an extrasolar planet.
rj
Another possibility is that the planet does not originate from the star it is orbiting. For example, the planet may have been in an unstable orbit around star 'A' and eventually escaped from star 'A' it traveled through space until it was caught in the gravitation of star 'B' and began to orbit. The orbit of the planet around star 'B' would be based more on the direction and angle it approached star 'B' as opposed to the spin of star 'B'
Just my theory.
it is only after a long journey that you know the strength of the horse.
No matter how much proof of intelligence and competence we send, the earthlings just don't get it.
In less than one day! http://www.newscientist.com/article/dn17613-second-backwards-planet-found-a-day-after-the-first.html
The purpose of writing is to inflate weak ideas, obscure poor reasoning, and inhibit clarity....Calvin