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The Moon’s Eastern Seas. Part 1: Formation & Evolution of the Moon Part 2: Lunar Libration Part 3: The Eastern Seas. Geologic timeline of Earth. 4570 Earth Formation. 1800 First Complex single-cell life. 380 First Vertebrate Land Animals. 230-65 Dinosaurs.
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The Moon’s Eastern Seas • Part 1: Formation & Evolution of the Moon • Part 2: Lunar Libration • Part 3: The Eastern Seas
Geologic timeline of Earth 4570 Earth Formation 1800 First Complex single-cell life 380 First Vertebrate Land Animals 230-65 Dinosaurs 80-55 Rocky Mts. Uplift 0.0117 Glaciers Retreat
Geologic timeline of Moon & Earth 4570 Earth Forms 4533 Moon Forms from Giant Impact
Formation & Evolution of the Moon Nectarian Nectaris, Humboldtianum, Humorum, Crisium, Serenitatis Pre-Nectarian NECTARIS Procellarum Insularum Marginis Fecunditatis Australe Tranquillitatis Nubium Smythii Grimaldi IMBRIUM Copernican Eratosthenian Imbrian ERATOSTHENES COPERNICUS NOW Pythagoras, Theophilus, Langrenus, Hercules Tycho, Aristarchus, Kepler Lava Flows ORIENTALE Surface Hardens Late Heavy Bombardment
Timeline for Lunar Lava Flows IMBRIUM NECTARIS COPERNICUS Nectarian ERATOSTHENES Pre-Nectarian ORIENTALE 50 NOW 40 Lunar Volcanic Activity Basalt Units 30 20 10
Beginning of the Late Imbrian Period Drawing by Don Davis
End of the Late Imbrian Period Drawing by Don Davis
Present Day Moon Drawing by Don Davis
Lunar Directions N W E S
The Eastern Seas N E In early February the 6-day-old Moon was Librated so that more of the eastern area was visible than usual.
Mare Humboldtianum Located in the Moon’s NE Corner Outer Basin is 600 Km in Diameter Formed during the Nectarian Period Inner Basin & Mare are 300 Km in Diameter The Basin formed during the Nectarian Period, and filled with lava during the Late Imbrian Named for Alexander von Humboldt by Johann H. Mädler Lunar Periods Late Heavy Bombardment
Johann Heinrich von Mädler Alexander von Humboldt • (September 14, 1769 – May 6, 1859) was a Prussian geographer, naturalist and explorer. Humboldt's quantitative work on botanical geography laid the foundation for the field of biogeography. (May 29, 1794 – March 14, 1874)one of the great and eminent astronomers of the 19th century. Has a crater on the Moon and one on Mars named for him.
Mare Smythii • One of the lowest Maria, 4 – 4.5 Km below the avg. Lunar Surface • Impact basin is Pre Nectarin, 350 - 400 Km in diameter • Southern floor is late Imbrian basalt. Northern floor is from the Eratosthenian period & may be only 1 – 2 billion years old. Named for Admiral William Henry Smyth (21 Jan. 1788 – 8 Sep.1865),English naval officer & astronomer. President Royal Astronomical Society. Published Bedford Catalogue with observations of 1604 double stars and nebulae (with a 5.9-inch refractor).
Mare Marginis (The Sea of the Edge) • Thought to be one of the oldest Maria on the Moon. About 200 Km north-to-south. • Apparently not area with a major impact basin. Appears to be a low-lying area where lava filled several cratered areas where the lunar crust was relatively thin. The lava flows are also thin, being only an estimated 1000 to 1700 feet thick. • The highland area is Pre-Nectarian and lava flows are probably Late - Imbrian
Mare Undarum Mare Spumans Mare Anguis • All three Maria are of Nectarin origin, with lava filling them during the Late Imbrian Period. (Serpent Sea) (150 Km long) (Sea of Waves) (240 Km dia.) (Foaming Sea) (140 Km dia.)
Mare Australe (The Southern Sea) • This 600 Km heavily-cratered basin was formed during the pre-Nectarin period, and filled with lava during the late Imbrian period. • The basin is located in the Southeast area of the moon, and half of the basin is on the far side, but can be seen (barely) during favorable librations.
References • The Modern Moon – a personal view • By Charles A. Wood • The Geologic History of the Moon (US Geological Survey Professional Paper 1348) –By Don E. Wilhelms • Wikipedia • “Eastern Seas” photo taken with 6” f/8 Refractor at prime focus, Canon Rebel DSLR, ISO 100, 1/250th second • http://www.lpod.org/cwm/DataStuff/pronounce/Introduction.htm
The End! Questions?