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Kepler Spots "Perfectly Aligned" Alien Worlds
astroengine writes "When NASA's Kepler space telescope started finding planets at odd angles to their parent stars, scientists wondered if our solar system's tidy geometry, with the planets neatly orbiting around the sun's equator, was an exception to the rule. That idea can be laid to rest thanks to an innovative use of the Kepler data which aligned three planets circling the sun-like star Kepler-30 with a giant spot on the star's surface. 'The planets themselves are not all that remarkable — two giant Jupiters and one super-Earth — but what is remarkable is that they aligned so perfectly,' astronomer Drake Deming, with the University of Maryland, told Discovery News."
I'm a software engineer so my knowledge is rather limited, but I'd have assumed that the orbits of planets would tend to be in the same plane as the spinning of the galaxy, so if you look at a mostly flat galaxy, you'll find mostly aligned orbits, and if a galaxy was more... "chaotic", the orbits would be likewise less aligned in respect with each other.
Well, each solar system has an invariable plane perpendicular to its aggregate angular momentum vector. The rotation of the star and the orbits of the planets tend to be quite close to this plane. The exception is when the orbits have been perturbed by passage of an object of significant mass at an angle to the plane. Note that the invariable plane of any particular solar system in a galaxy is not necessarily similar to that of the galaxy as a whole, although aggregated over all solar systems in the galaxy they are the same.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
I'd have assumed that the orbits of planets would tend to be in the same plane as the spinning of the galaxy
If you consider that the Milky Way is not aligned with the ecliptic then you should see that the assumption is erroneous with respect to the only solar system we understand well.
I agree. Light speed is too slow. We must go straight to Ludicrous Speed!
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
Disclaimer: IAAAA (I am an amateur astronomer).
The moon orbits at a mean inclination of 5.something degrees to the ecliptic. If it were synchronised to the equatorial plane we wouldn't have nearly as many eclipses (lunar or solar) as we do. In fact, we'd have about 1/50 the number.
Operation Guillotine is in effect.
Universe is 2D.
The 3D stuff is just to milk more money!
HOWEVER, and here's the paradox: if not all stars have orbiting planets, then the number of stars with orbiting planets is less than infinite, ie, finite.
Bzzzt! Fail - thanks for playing.
Once you start playing with infinite numbers you have to be very careful with concepts like "less than" or "more than". Just because you can demonstrate that one set is in some way smaller than another infinite set does *not* demonstrate that the smaller one is finite.
Consider the set of natural numbers - 1,2,3,4 etc. This is infinite. Then consider the set of even natural numbers - 2,4,6,8 etc. Clearly there are members of the first set which are not members of the second set, and so one might be tempted to conclude that the second set is in some way smaller, and therefore by your argument, finite.
In fact one can set up a one-to-one mapping between the two sets:
12
24
36
etc. and thus both sets have precisely the same (infinite) number of members.
Actually, I can.
Even assuming that the orbital inclination of both planets were identical, those orbits undergo what's known as apsidal precession. This is the movement of apoapsis (the furthest point of the orbit) around the primary over time - the orbit orbits. For Earth this varies between 100,000-400,000 years, and is tidally dependent. Ergo, the relative angle of inclination between planets changes and while Earth is below the ecliptic, the orbit of Venus at that point, even if the planet was in the same orbital position (ie between Earth and Sol), may be above the ecliptic hence no transit occurs.
This also happens with the Moon. Fortunately the systems are stable enough that we can predict when transits and eclipses will occur by concentrating only on dates and times where ascending and descending nodes of their orbits intersect the ecliptic. The great thing about the Moon is that it crosses the ecliptic exactly twenty six times per year, so we can predict with reasonable certainty from the off that solar and lunar eclipse patterns will repeat with fair precision every 6585 days, or every 223 Lunar orbits. (approximately 18 years).
Operation Guillotine is in effect.
> those toy 2d simulators of gravity of stars and planets: start with a chaotic configuration, let it evolve for some time, and see how the stuff often evolves in one big central blob with possibly some circular orbits and short lived elliptical ones
The technical term is called N-Body simulation/problem and is impossible to solve an exact solution with our current mathematics and computers where N > 3.
http://en.wikipedia.org/wiki/N-body_simulation
http://en.wikipedia.org/wiki/N-body_problem
I found one demo here ...
http://michael.peopleofhonoronly.com/dev/nbody.html
In order for the simulator to work properly, every simulator has to use a hack: gravity has infinite speed, which contradicts the mainstream assumption that gravity is limited to the speed of light.
Another anomaly is that the the galaxy "seems" to rotate in lock-step.
http://en.wikipedia.org/wiki/Galaxy_rotation_curve
It "appears" the orbits of the planets also seem to be quantized.
Celestial Mechanics is not going to be "solved" anytime soon.