Planet Orbit—Lunar Orbit Resonances and the History of the Earth-Moon System

Abstract

After reviewing a number of geology and astronomy textbooks, a reader gets the feeling that the Moon is not all that important in the development of our habitable planet. The Moon raises ocean tides on the planet and it serves as a “night lantern” and these features of the Moon have been important for some human endeavors (e.g., in production of food crops in coastal areas and, in some special circumstances, in military campaigns at specific times in human history). But the question posed here is: HAS THE MOON BEEN IMPORTANT IN THE DEVELOPMENT OF PLANET EARTH INTO THE ONLY PLANET THAT WE KNOW OF THAT IS HABITABLE TODAY, AFTER NEARLY 4.6 BILLION YEARS OF GEOLOGICAL EVOLUTION?

“Another resonance of the above type is also stable. This keeps the perigee in step with jupiter’s orbital motion at a/a _earth  = 53.4. However, variations in the Earth’s orbital eccentricity seem to make capture into this latter resonance unlikely (Yoder, private communication, 1977). Should capture have occurred, however, the effects on orbital history would be profound and significant heating of the Moon would occur if the eccentricity were driven to sufficiently large values.”

From Peale and Cassen (1978, p. 260).

“If we choose starting positions of Venus and the earth that correspond to an inferior conjunction of Venus with the sun as observed from the earth, eight years later there would be a similar conjunction at which the sun and Venus would occupy positions in the sky very close to their starting positions. Consequently, conjunctions of the type discussed in the previous section should recur at eight-year intervals. In the same way, other phenomena of Venus such as superior conjunctions, eastern elongations, and western elongations should exhibit eight year cycles.”

“After five conjunctions or eight years, they end up where they started.”

From Chapman (1986, pp. 340–341).

Appendix

Fig. 8.40

Summary diagrams for some orbit and tidal parameters for the Cool Early Earth era and for Early Archean time (4.6–3.6 Ga). a Set 1 parameters. b Set 2 parameters

Fig. 8.41

Composite diagram for some orbit and tidal parameters for the Cool Early Earth era and for Early Archean time (4.6–3.6 Ga)

Fig. 8.42

Summary diagrams for some orbit and tidal parameters for part of the Archean Eon (3.6–2.6 Ga). a Set 1 parameters. b Set 2 parameters

Fig. 8.43

Composite diagram for some orbit and tidal parameters for part of the Archean Eon (3.6–2.6 Ga)

Fig. 8.44

Summary diagrams for some orbit and tidal parameters for the Early Proterozoic to Late Proterozoic eras (2.6–1.1 Ga). a Set 1 parameters. b Set 2 parameters

Fig. 8.45

Composite diagram for some orbit and tidal parameters for the Early Proterozoic to Late Proterozoic eras (2.6–1.1 Ga)

Fig. 8.46

Summary diagrams for some orbit and tidal parameters for the Late Proterozoic and Early Paleozoic eras (1.1 Ga to Present). a Set 1 parameters. b Set 2 parameters

Fig. 8.47

Composite summary diagram for some orbit and tidal parameters for the Late Proterozoic and Early Paleozoic eras (1.1 Ga to Present)