Coplanarity of solar system & Milky Way
Name: Robert T Kinner
Is the disk of our solar system coplanar with the disk of the Milky
Way (or is it tilted)?
It is tilted! Something like 30-50 degrees. Somebody else probably knows
better than me though.
It is 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 are
not 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