2007-04-02 12:28:14 · 6 answers · asked by Alfonso G 1 in Science & Mathematics ➔ Astronomy & Space
The sun, actually; in one of Isaac Asimov's collections of science essays he calculated that the moon's orbit is everywhere concave toward the sun, meaning that the moon isn't orbiting the earth, but is in a solar orbit that it shares with the earth. If it were orbiting the earth then its orbit would be convex relative to the sun at some points.
2007-04-02 13:17:03 · answer #1 · answered by Isaac Laquedem 4 · 0⤊ 0⤋
Any two bodies orbit around their common center of mass. In the case of the Earth-Moon system, the Earth is so much more massive than the Moon (81 times as heavy), that the focus of the orbit is inside the Earth. So it is more or less correct to say that the Moon orbots around the Earth, but it is even more accurate to say that they both orbit around a point that is 1/81 of the way between the center of the Earth and the center of the Moon. That point is about 3/4 of the way between the center of the Earth and the surface. That is the focus of the orbit.
2007-04-02 13:06:51 · answer #2 · answered by Astronomer1980 3 · 0⤊ 0⤋
I suspect the two focal points of the eliptical orbit are between the earth and the moon. The orbit isn't eccentric enough to have the earth as a focus.
2007-04-02 12:34:55 · answer #3 · answered by Gene 7 · 0⤊ 0⤋
the earth.
the moon's orbit is almost completely circular
so there probably isn't another focus.
the moon goes around the earth.
2007-04-02 12:35:53 · answer #4 · answered by BonesofaTeacher 7 · 0⤊ 0⤋
If it isn't the Earth, we are in deep trouble.
2007-04-02 13:38:55 · answer #5 · answered by Mike1942f 7 · 0⤊ 0⤋
a planet called EARTH
2007-04-02 12:31:24 · answer #6 · answered by Firestar 2 · 1⤊ 0⤋