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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.'"
The way I read it is that the GP is not saying that the star CAUSED the retrograde orbit -- he's asking why everyone's asking how the PLANET's orbit changed rather than asking why the star's spin changed. For a car analogy.. it's like asking why the car pissed off the dog that's chasing it rather than why the dog is chasing the car.
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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
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
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.
Depends on what gets perturbed, I guess.
Try not to think just in two dimensions. Imagine the orbit as a very large ring. Instead of thinking of it shrinking, imagine the ring pivoting out of the usual orbital plane. Imagine this ring slowly rotating. Eventually, it'll settle back to the plane yet the planet will be orbiting backwards relative the the original and the star's rotation.
You have little understanding of how science works and how scientists actually think. If you want to talk about cherished theories that can't be changed talk to creationists and theologians. If you want to talk about theories that explain and simulate the universe that are regularly changed, usually but not always gradually, learn the scientific method and about science.
I have been trained as a physicist and a scientist and the first lessons they begin teaching(besides calculus and the other basic courses) are that science is the process of curiosity, reason and doubt. It is a collaborative effort that is larger than any single person and it is a slow struggle where answering one question means opening up many many more. It is the process of expanding the universe by exploring the world around us and seeing how big, vast and wonderful our lives and this world really are.
Religion too often gives us the like of seven days, 6000 years and a wet ball of mud to live on, with harps and clouds if you've been good afterward. Its comforting but it is small.
The "dust cloud" theory only states that the majority of planets should rotate with their sun. There are a number of known mechanisms, some discusses in TFA, which can produce retrograde motion. We have several moons in the solar system showing retrograde motion. So this does absolutely nothing to disturb current theories of planet formation - you would have to find dozens of these to do that. It just appears that, in this case, one of several interesting events must have happened, and it might be worth looking for evidence of such an event. For example, if it were a near collision, it would be worth backtracking the paths of nearby stars to see if they were candidates for this decision.
This is not a "the current rules are broken" announcement, but a "hey, something interesting" announcement.
Consciousness is an illusion caused by an excess of self consciousness.