RE: Full Sun - Half Moon?
September 26, 2013 at 11:33 am
(This post was last modified: September 26, 2013 at 11:38 am by pocaracas.)
(September 26, 2013 at 10:14 am)Doubting Thomas Wrote:(September 26, 2013 at 9:39 am)pocaracas Wrote: 3 points always make a plane
I thought two wings, a fuselage, and a tail make a plane?
It's a plane! Not a plane!
(September 26, 2013 at 10:07 am)Stimbo Wrote: Granted, but the Sun-Earth Moon triangle isn't static. Things get complicated when one of those points is orbiting another in such a way as to cause its apparent position as seen from the third point to be above or below the second.
If the system formed a stable planar triangle, we would get solar and lunar eclipses every alternate fortnight.
The "How many Earths?" piece has an excellent illustration of this, in the slide about Kepler only being able to detect planets via the luminosity method when the planet passes in front of its star. If its orbit is outside the plane of this line of sight, this method won't see the planet.
There you go talking about orbital planes... I know the two orbits are not co-planar, but at any moment, the system sun - earth (surface, where the person can see something) - moon always forms a triangle (always changing) on a non-static plane.
