Is The Earth - Moon System A Double Planet?
Posted: Sun Mar 31, 2019 4:37 pm
By some definitions one can argue that the Moon is actually the smaller
planet in a two - planet system, rather than a satellite. But since the
center of gravity of the Moon’s orbit is within the Earth, most define
it as a satellite. The center of mass (Barycentric coordinates [astronomy])
is within the Earth and about 4670 km from the center of the Earth.
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Proportionally, the Moon is much larger in comparison to its
primary than virtually every other satellite in the solar system,
except maybe Pluto’s moon Charon. This is one reason some define
it as part of a double planet system instead of a satellite.
Pluto - Charon might count as a double planet, or rather double
dwarf planet, since the Barycentre lies above the center of Pluto.
The definitions are still unclear.
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planet in a two - planet system, rather than a satellite. But since the
center of gravity of the Moon’s orbit is within the Earth, most define
it as a satellite. The center of mass (Barycentric coordinates [astronomy])
is within the Earth and about 4670 km from the center of the Earth.
60667
- 60667.jpg (79.74 KiB) Viewed 1513 times
primary than virtually every other satellite in the solar system,
except maybe Pluto’s moon Charon. This is one reason some define
it as part of a double planet system instead of a satellite.
Pluto - Charon might count as a double planet, or rather double
dwarf planet, since the Barycentre lies above the center of Pluto.
The definitions are still unclear.
60666
- 60666.jpg (53.83 KiB) Viewed 1513 times