Coplanarity of the Solar System & Milky Way
Name: robert t kinner
Date: 1993 - 1999
Is the disk of our solar system coplanar with the disk of the Milky Way?
It's tilted! Something like 30-50 degrees. Somebody else probably
knows better than me though.
It's actually more like 90 degrees!
The plane of the Solar System is called the ecliptic. The plane that
stars _appear_ to rotate in, as seen from a point on the Earth, is
called the Celestial equator. The angle between the ecliptic and the
Celestial equator is, of course, equal to the angle between the Earth's
rotation axis and the Solar System's axis, 23.5 degrees. The Galactic
Equator is tilted about 63.5 degrees from the Celestial equator,
in the opposite direction of the ecliptic. So why aren't all these
rotations coplanar? like one might expect from Conservation of Angular
Momentum? We think that when the Solar System was just a rotating,
collapsing cloud of gas and dust, a passing star came close enough
to change its axis of rotation.
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Update: June 2012