This is an picture of the Lunar Prospector spacecraft, which was used to
determine the size of the Moon's core.
Click on image for full size
Image courtesy of NASA
Earth's Moon--A Chip Off The Old Block?
News story originally written on March 19, 1999
Scientists have used data from the Lunar
spacecraft to determine that the Moon
has a small core. This
finding supports the formation theory
the Moon was once part of Earth
ejected following a large impact
"This impact occurred after the Earth's iron core had formed, ejecting
rocky, iron-poor material from the outer shell into orbit," explained Dr.
Alan Binder, principal investigator for Lunar Prospector. "It was this
material that collected to form the Moon."
Lunar Prospector used gravity measurements to determine the size of the Moon's core
. It contains less than
four percent of the Moon's mass. The Earth's core
other hand contains 30 percent of our planet's mass.
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