
#1
Aug1209, 11:34 PM

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P: 25,928

I was speaking with a friend about this today, I don't see a thread on it.




#3
Aug1309, 12:16 AM

P: 105

That's nothing. Kapteyn's Star orbits the galaxy retrograde.




#4
Aug1309, 07:32 AM

P: 606

Newfound planet orbits backward
What happens when they flush their toilets?




#5
Aug1309, 07:40 AM

P: 75





#7
Aug1309, 12:08 PM

P: 502

How does one measure the axis of rotation of a distant star?




#8
Aug1309, 07:34 PM

P: 943





#9
Aug1309, 09:05 PM

P: 1,070





#10
Aug1309, 10:38 PM

P: 15,325





#11
Aug1409, 12:04 AM

P: 3,408

What is the chance that a planetsized object may be captured exclusively by a star's gravitation, to orbit against the rotation of a the star? Perhaps smaller planetoids (like Pluto), difficult to see outside out own solar system, would be much more likely to be captured in the first place.
Can a planet in a binary system have a oscillating trajectory? My guess is that it would be more likely ripped apart or fall into a star. 



#12
Aug1409, 01:04 AM

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P: 39,615

I deleted a 2012 doom post by a regular member and the responses. Please check your references before posting obvious stupid stuff. Snopes.com is a good place to start for obvious stuff. Thanks.




#13
Aug1409, 09:06 AM

P: 943





#14
Aug1409, 11:30 AM

P: 15,325

It orbits the sun (definition of a year) every 224 days, but it rotates on its own axis (definition of a day) every 243 days. The fact that the axial rotation is slower than the orbit is tantamount to a retrograde rotation. 



#15
Aug1409, 11:56 AM

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P: 2,352





#16
Aug1409, 08:36 PM

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#17
Aug1409, 10:22 PM

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P: 1,327

I read about this too on Wednesday, It was listed on BBC Science News. So the planet's name WASP17 has to do with the 'Wide Area Search for Planets' consortium of UK universities
Very interesting that we are able to deduce this kind of information for planets orbiting other stars. 



#18
Aug1409, 10:46 PM

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We don't know yet if there is a cause for a particular resonance between the Earth and Venus or whether it is just a coincidence. Venus' rotation and orbit are such that whenever Earth and Venus are in inferior conjunction (when they are at their closest to each other) Venus always presents the same side to the Earth. There is a formula to calculate tidal locking times. it is [tex]t= \frac{\omega a^6 I Q}{3GM^2 K_2 R^5}[/tex] [itex]\omega[/itex] is the initial spin rate (radians/sec) a is the semimajor axis of the orbit I is the moment of inertia of the planet Q is the dissipation factor G is the gravitational constant M is the mass of the sun [itex]K_2[/itex] is the Love number R is the radius of the planet. However, Q and K2 are not well known except for the case of the Earth and moon. 


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