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All the prevailing, [[atheistic]] theories of the origin of the [[Moon]] were completely disproven by the lunar landings and studies of the lunar rocks afterwards.  The material lacked [[iron]] that permeates the [[Earth]]'s crust.

All the prevailing, [[atheistic]] theories of the origin of the [[Moon]] were completely disproved by the lunar landings and studies of the lunar rocks afterwards.  The material lacked [[iron]] that permeates the [[Earth]]'s crust.

Specifically, each of these prevailing scientific theories were disproven by the lunar landings:<ref name="PSI">Planetary Science Institute: [http://www.psi.edu/projects/moon/moon.html The Origin of the Moon]</ref>

Specifically, each of these prevailing scientific theories were disproved by the lunar landings:<ref name="PSI">Planetary Science Institute: [http://www.psi.edu/projects/moon/moon.html The Origin of the Moon]</ref>

*The [[Moon]] formed in an orbit around Earth at the same time that Earth formed.

*The [[Moon]] formed in an orbit around [[Earth]] at the same time that Earth formed.

**This theory was disproven upon learning that the Moon has proportionally far less iron in it than the [[Earth]].

**This theory was disproved upon learning that the [[Moon]] has proportionally far less iron in it than the [[Earth]].

*The [[Moon]] formed in a part of the solar system that was low in iron, and was later captured into an orbit arount the Earth.

*The [[Moon]] formed in a part of the solar system that was low in iron, and was later captured into an orbit around the Earth.

**This was also disproven by examination of lunar rocks, which exhibit the same oxygen isotope composition as the Earth, unlike rocks known to come from other sources in the solar system, e.g. [[Mars]].

**This was also disproved by examination of lunar rocks, which exhibit the same oxygen isotope composition as the Earth, unlike rocks known to come from other sources in the solar system, e.g. [[Mars]].

*The [[Earth]] was originally spinning so fast that it spun off a fragment of lower density (iron-poor) material which became the [[Moon]].

*The [[Earth]] was originally spinning so fast that it spun off a fragment of lower density (iron-poor) material which became the [[Moon]].

== Giant-Impact Model ==

== Giant-Impact Model ==

For ten years after the lunar landings, non-creationist scientists lacked any accepted theory about the Moon's origin.  In 1984, an international meeting was convened in Kona, Hawaii, for the purpose of agreeing on a new theory for the origin of the Moon.<ref>''Id.''</ref>  The attendees at the meeting agreed upon the following "giant-impact model," which was first proposed in 1975 but which had not yet been generally accepted.<ref>''Id.''</ref>

For ten years after the lunar landings, atheistic scientists lacked any accepted theory about the [[Moon]]'s origin.  In 1984, an international meeting was convened in Kona, [[Hawaii]], for the purpose of agreeing on a new theory for the origin of the [[Moon]].<ref>''Id.''</ref>  The attendees at the meeting agreed upon the following "giant-impact model," which was first proposed in 1975 but which had not yet been generally accepted.<ref>''Id.''</ref>

This theory proposes an impact with a large planetesimal (asteroid-like body) released a great quantity of debris into orbit, a portion of which collected under the influence of gravity. There is no direct evidence for this theory.  It is supported by non-creationist scientists, however, because only it might explain the following:

This theory proposes an impact with a large planetesimal (asteroid-like body) released a great quantity of debris into orbit, a portion of which collected under the influence of gravity. There is no direct evidence for this theory.  It is supported by atheistic scientists, however, because only it might explain the following:

**The lack of iron, provided the impact of the planetesimal happened relatively late in the earth's formation and after the Earth's iron had sunk towards its core.  In that manner the Moon could pick up mantle from the Earth that has less iron.  Most of the planetesimal itself would have sunk into the earth's core.

**The lack of [[iron]], provided the impact of the planetesimal happened relatively late in the earth's formation and after the [[Earth]]'s [[iron]] had sunk towards its core.  In that manner the [[Moon]] might have picked up mantle from the Earth that has less [[iron]].  Most of the planetesimal itself would have sunk into the earth's core.

**The similar oxygen isotope composition between the Moon and Earth could be explained by such a collision, provided the Moon were then formed from debris dislodged from the Earth by the collision.

**The similar oxygen isotope composition between the [[Moon]] and [[Earth]] could be explained by such a collision, provided the Moon were then formed from debris dislodged from the [[Earth]] by the collision.

**A high-velocity collision might be sufficient to release enough energy to place a substantial mass of the Earth's crust into orbit.

**A high-velocity collision might be sufficient to release enough energy to place a substantial mass of the Earth's crust into orbit.

:Unfortunately, researchers have had trouble getting the giant-impact model to work without the contrivances that scuttled earlier theories.

:Unfortunately, researchers have had trouble getting the giant-impact model to work without the contrivances that scuttled earlier theories.

:Four facts and three parameters is a recipe for contradiction. To explain the moon's low iron content, you need to avoid a grazing collision (corresponding to a large impact angle), lest too much of the impactor's iron spill into orbit. Then, to explain the angular momentum, you need to compensate for the smallish angle with a hefty impactor. Then, to explain the moon's mass, you need to adjust the proto-Earth's mass. In the end, you might find that the total mass is incorrect.

:Four facts and three parameters is a recipe for contradiction. To explain the moon's low iron content, you need to avoid a grazing collision (corresponding to a large impact angle), lest too much of the impactor's iron spill into orbit. Then, to explain the angular momentum, you need to compensate for the smallish angle with a hefty impactor. Then, to explain the moon's mass, you need to adjust the proto-[[Earth]]'s mass. In the end, you might find that the total mass is incorrect.

''Scientific American'' concluded:<ref>''Id.''</ref>

''Scientific American'' concluded:<ref>''Id.''</ref>