100%(1)1 out of 1 people found this document helpful
This preview shows pages 1–3. Sign up to view the full content.
1Astro 102/1041Lecture #14: •Origin of the Moon• Observations•Classical models for theformation of the Moon•A relatively new idea: the Giant Impact theory• Reading:– Chapters 8.4, 9.3Astro 102/1042Moon Hoax?• Apollo conspiracy theories retain a limited following• “Conspiracy Theory: Did We Land on the Moon?” (Fox TV, 2001) – NASA faked Moon landings in Nevada desert (Area 51)ÎThoroughly discredited at:• Do youthink 400,000 people could keep a secret this long?Astro 102/1043The Main PointThere are four main hypotheses for the origin of the Moon. The most widely accepted among astronomers today is the giant impact hypothesis.Astro 102/1044Observations•Any successful theory for the origin of the Moon must account for everything we know about the Moon now.•Facts:–The Moon’s mantle composition is in some ways similar to Earth’s (oxygen isotopes), and in other ways different (volatile abundances)–The Moon is much less dense than Earth (no large iron core)–The Moon orbits in the same direction as the Earth rotates–The Moon is slowly drifting away from the Earth•The Moon was once much closer to the Earth
has intentionally blurred sections.
Sign up to view the full version.