it has cleared its orbit of other objects
Dragon Star wrote:Yep, in fact it will just crush you're entire body when it collides to earth. :P
Enzo wrote:A few days ago the CBS morning news announced that scientists would be deciding to increase the number of planets "in the Milky Way" to 12 from the current 9. Looks like we must be alone after all.
Dragon Star wrote:Yea, they changed their criteria the next day I think. That's what you get from the media before a actual decision is made.
teri tait wrote:Well that's just typical, an antichrist named "John Doe". The only thing worse would be "Joe Sixpack"
Dragon Star wrote:That's what you get from the media before a actual decision is made.
Lonewulf wrote:Hey, I support Pluto not being considered a "real" planet. It was just a large asteroid anyways, with a wonky revolution.
Besides, who REALLY cares about Pluto? Really? The only "good" mark about it that makes it memborable (besides the small amount of planets in the first place) is that it's farthest away from the Sun. Wow... it's memorable because it really sucks so much.
It's small, it's far away, and it really doesn't matter.
Heid the Ba' wrote:umop: was there some interminable argument on BABB/BAUT about the Moon and whether it actually orbited the Sun or Earth? I never got my head round that one, the same as I never quite got sidereal days.
umop ap!sdn wrote:A sidereal day is the time it takes for a given fixed star to appear to return to the same position in the sky (ignoring precession and nutation). On Earth it's about 23 hours 56 minutes. During that time the Earth advances in its orbit so that the Sun appears to have moved with respect to the background stars. It takes an extra 4 minutes to catch up with the Sun's new apparent position, thus making a 24 hour day.
umop ap!sdn wrote:Basically, some argue that the Earth and Moon are 2 different planets orbiting the Sun at roughly the same distance and mean anomaly, perturbing each other's orbit so that they remain in close proximity. One point in favor of this arguement is that the Moon's trajectory appears concave even when seen from the Sun. One point against it is the fact that the Earth-Moon barycenter is beneath the Earth's surface, thus the Moon is actually orbiting the Earth.
Lonewulf wrote:Er, and how about the fact that the moon revolves around the earth in a predictable fashion, to the point where we set our clocks by it? I can't imagine the moon moving around the Earth by revolving around the sun... it would take a bit of astronomical acrobatics.
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