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As I understand it, the fact that the moon is tectonically active implies that there still is enough heat in the moon's core to cause tectonic activity. (To an

As I understand it, the fact that the moon is tectonically active implies that there still is enough heat in the moon's core to cause tectonic activity. (To anyone who's wondered as well)

simonh 7y ago
The article talks about these movements occurring close to apogee (the point in the Moon's orbit when it's furthest from the earth), so it looks like this activity is driven by gravitational tidal forces rather than internal heat.
acqq 7y ago
The tidal forces are known topic: https://www.teachastronomy.com/textbook/The-Earth-Moon-System/Effects-of-Tidal-Forces/ https://www.teachastronomy.com/textbook/The-Earth-Moon-Syste... "Even when there's no water to respond to tidal forces, the solid mass of a planet feels the stress caused by these forces. In fact, tidal forces can heat the interior of a satellite in an elliptical orbit. In that case, the satellite comes closer to the planet during one part of its orbit and there it's subjected to strong stretching forces. As it moves away from the planet the stress is partly released and the body relaxes back toward a more spherical shape. This continual flexing of the satellite creates heat through internal friction, in the same way, that if you flex a tennis ball enough times it becomes warm. This effect is called tidal heating. The more elliptical the orbit, the stronger the tidal heating. Jupiter's large Galilean satellites experience this kind of heating — enough to produce extensive volcanism on Io and possibly create liquid-water oceans beneath the surface of Europa." The question is how the Moon could be more precisely modeled, and if some refinements to our models used on Earth too could be done, and for all that more measurements would be needed. The paper uses only those made from 1969 to 1977 from the seismometers placed by four Apollo missions, and tries to interpret the data with newer methods than what was done before with the existing measurements, but since 1977 there were no new measurements. Also: https://physicsworld.com/a/radioactive-decay-accounts-for-half-of-earths-heat/ https://physicsworld.com/a/radioactive-decay-accounts-for-ha... "About 50% of the heat given off by the Earth is generated by the radioactive decay of elements such as uranium and thorium, and their decay products. That is the conclusion of an international team of physicists that has used the KamLAND detector in Japan to measure the flux of antineutrinos emanating from deep within the Earth."
ramijames 7y ago
Does this mean the moon likely has a magnetosphere?

As I understand it, the fact that the moon is tectonically active implies that there still is enough heat in the moon's core to cause tectonic activity. (To anyone who's wondered as well)

simonh 7y ago

The article talks about these movements occurring close to apogee (the point in the Moon's orbit when it's furthest from the earth), so it looks like this activity is driven by gravitational tidal forces rather than internal heat.

acqq 7y ago

The tidal forces are known topic: https://www.teachastronomy.com/textbook/The-Earth-Moon-System/Effects-of-Tidal-Forces/ https://www.teachastronomy.com/textbook/The-Earth-Moon-Syste... "Even when there's no water to respond to tidal forces, the solid mass of a planet feels the stress caused by these forces. In fact, tidal forces can heat the interior of a satellite in an elliptical orbit. In that case, the satellite comes closer to the planet during one part of its orbit and there it's subjected to strong stretching forces. As it moves away from the planet the stress is partly released and the body relaxes back toward a more spherical shape. This continual flexing of the satellite creates heat through internal friction, in the same way, that if you flex a tennis ball enough times it becomes warm. This effect is called tidal heating. The more elliptical the orbit, the stronger the tidal heating. Jupiter's large Galilean satellites experience this kind of heating — enough to produce extensive volcanism on Io and possibly create liquid-water oceans beneath the surface of Europa." The question is how the Moon could be more precisely modeled, and if some refinements to our models used on Earth too could be done, and for all that more measurements would be needed. The paper uses only those made from 1969 to 1977 from the seismometers placed by four Apollo missions, and tries to interpret the data with newer methods than what was done before with the existing measurements, but since 1977 there were no new measurements. Also: https://physicsworld.com/a/radioactive-decay-accounts-for-half-of-earths-heat/ https://physicsworld.com/a/radioactive-decay-accounts-for-ha... "About 50% of the heat given off by the Earth is generated by the radioactive decay of elements such as uranium and thorium, and their decay products. That is the conclusion of an international team of physicists that has used the KamLAND detector in Japan to measure the flux of antineutrinos emanating from deep within the Earth."

ramijames 7y ago

Does this mean the moon likely has a magnetosphere?