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.
Shop Windows to the Universe Science Store!
Learn about Earth and space science, and have fun while doing it! The games
section of our online store
includes a climate change card game
and the Traveling Nitrogen game
You might also be interested in:
The construction of NASA's Lunar Prospector has been completed. This spacecraft will travel to the Moon in September 1997 to make the first complete compositional and gravity maps of the Moon. The Lunar...more
You may wonder how it is that scientists know what the inside of a planet is like. The interior of a moon or planet can be closely determined from spacecraft navigation data when a spacecraft passes by...more
It was another exciting and frustrating year for the space science program. It seemed that every step forward led to one backwards. Either way, NASA led the way to a great century of discovery. Unfortunately,...more
The Space Shuttle Discovery lifted off from Kennedy Space Center at 2:19 p.m. EST, October 29th. The sky was clear and the weather was great as Discovery took 8 1/2 minutes to reach orbit for the Unitied...more
A moon was discovered orbiting the asteroid, Eugenia. This is only the second time in history that a satellite has been seen circling an asteroid. A special mirror allowed scientists to find the moon...more
Will Russia ever put the service module for the International Space Station in space? NASA officials are demanding an answer from the Russian government. The necessary service module is currently waiting...more
During a period of about two days in early May, 1998, the ACE spacecraft was immersed in plasma associated with a coronal mass ejection (CME). The SWICS instrument on ACE, which determines unambiguously...more