Moons: their origin, age, & recession

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yet to produce a single observed example of a planet or a moon being formed?

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Try looking real carefully at a picture of our moon, or of Mercury. See those ring-things peppered all over them? Them's craters. These bodies have got lots and lots of them. That's because even though impacts are fairly rare events now, they were much more common just after the solar system formed, an era called the late heavy bombardment. How do we know that? A few reasons.1.) Crater counting. The older a body is, the more craters it will have, unless geological processes erase the evidence. We can also tell the relative ages of craters when they are superimposed:

This is on Mars.

Impacts aren't very common today, so where did all those craters come from? Once we have a starting point, such as radiometric ages for lunar rocks (hello, how many times has Onifre mentioned this?), then crater counting is a simple technique to use.2.) Observed protoplanetary discs, which are what the nebular hypothesis predicted we'd find, and how our own solar system is likely to have begun. There is evidence that as they age (and become plain ol' planetary disks), there are significant collisions within them: Source

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The Castor co-moving group of stars containing Vega and Fomalhaut has recently been isolated. Using data from the Hipparcos satellite telescope the Castor group was found to have an estimated age of 200 100 million years. This indicates that the infrared excesses seen around Vega and Fomalhaut are likely due to a disk of debris from colliding planetesimals rather than a protoplanetary disk. Successful imaging of Fomalhaut's disk by the Hubble Space Telescope confirms this.

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Thing is, the collisions (and moon captures) are more likely to happen when there is lots of stuff floating around. There are other possible contributing factors to this as well, in the case of our solar system, such as the migration or destruction of planets.If you look around though, the very things you're claiming to be a little bit funny (or whatever) are evidence of the tumultuous past of our solar system: retrograde moons in eccentric orbits, the extreme tilt of Uranus, possibly the very slow retrograde rotation of Venus, etc.The question to you is, when the evidence is so strong that this is how it happened, how can you show that Goddidit, and why? Would it be because . . . he likes to spend his time watching planets rotate backwards or something?Edited by LindaLou, : No reason given.Edited by LindaLou, : No reason given.Edited by LindaLou, : No reason given.

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if there were several such occurrences on the moon over the last several milleniums then the time frame of evolutionary cosmology concerning the moon is blown out of the water.

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Don't you wish. There's that niggly issue of the fact that crater counting is done in conjunction with radiometric dates for moon rocks. That uncomfortable fact you keep ignoring. Here, I'll help you with it: Radiometric Ages of Some Mare Basalts Dated by Two or More Methods

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I would suggest you read my posts on the volcanic activity that has been repeatedly sighted by credible witnesses over the centuries. My evidence is based on observation.

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People centuries ago who saw stuff and gave their interpretations of it? You realise how many people today see stuff and do the same thing, i.e. identifying aircraft and weather balloons as alien spacecraft?

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Yours is not.

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You didn't read my last post then. You couldn't have anyway, because you replied to it so quickly. I'll hazard a guess that you're not interested in what anyone else is saying here either, even though it's hilariously proving that you don't have a clue what you're talking about.

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and that this rate has been approximately constant since the late Precambrian."

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There is plenty of research out there on tidal rhythmites which are older than this too. For example: Geological Constraints on the Precambrian History of Earth's Rotation and the Moon's Orbit

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Paleotidal and paleorotational values provided by late Neoproterozoic (∼620 Ma) tidal rhythmites in South Australia are validated by these tests and indicate 13.1 0.1 synodic (lunar) months/yr, 400 7 solar days/yr, a length of day of 21.9 0.4 h, and a relative Earth-Moon distance a/a 0 of 0.965 0.005. The mean rate of lunar recession since that time is 2.17 0.31 cm/yr, which is little more than half the present rate of lunar recession of 3.82 0.07 cm/yr obtained by lunar laser ranging . . . The combined rhythmite data give a mean rate of lunar recession of 1.24 0.71 cm/yr during most of the Proterozoic (2450-620 Ma), suggesting that a close approach of the Moon did not occur during earlier time. Concentrated study of Precambrian tidal rhythmites promises to illuminate the evolving dynamics of the early Earth-Moon system and may permit the lunar orbit to be traced back to near the time of the Moon’s origin.

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So we're looking at over half of the earth's geological history and the evidence from sedimentary rock whose deposition rate was influenced by tides, shows us that the moon was nowhere near perilously close.I can't help but notice (as has been observed by at least one other person on this thread) that you will use one kind of evidence to try to support your argument, and reject that same kind of evidence when it doesn't suit your purposes. I don't recall you telling us how old you think the earth is but I assume you believe it to be 6,000 years. Rhythmites, particularly varves, are some of the best evidence that the earth is much, much older than this, though that's a topic for another thread.

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direct eyewitness testimony of the dozens of observers to volcanic activity on the lunar surface

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Problem is, these are accounts of people looking at the moon and seeing stuff. Some are hundreds of years old. We can't talk to any of these people today and we can't be certain about the reliability of such historical testaments (no doubt difficult for a Biblical literalist to understand but there you go). I've had a look at Herschel's claims and it's difficult to distinguish what he actually saw from what he assumed he saw, since the two are pretty well merged (i.e. he assumed that there were volcanoes on the moon so that's what he thought he was seeing). Nothing he described is incongruous with a meteor impact, so why by your reckoning is this not an acceptable possibility? By the way, you do know that people used to think they were seeing alien-sculpted canals and green vegetation on Mars? Using your brand of epistemology, we should believe this too. I guess the Martians got rid of all the evidence before we built better telescopes and then started sending probes and rovers out there. Clever.Actually, I think the biggest problem you have with your young moon idea is radiometric dates for moon rocks. You made the silliest of hand-waving gestures by saying that they're simply based on preconceived notions. You honestly don't seem to realise that saying, "not true" is not an acceptable attack on any kind of evidenced theory or process. Slevesque tried to tell you this. The fact that you maintain this attitude with Cavediver, a physicist and cosmologist, is an endless source of amusement.Thing is, the decay rates of radioactive isotopes have nothing to do with preconceived notions. This is like saying that we only have a 24-hour day because we programmed our watches with preconceived notions about how long a day ought to be. You need to explain, using evidence, your objections to radiometric dating of moon rocks, or else your whole idea flies out the window. In Message 92 I gave you some dates to look at. Notice that these are dates obtained by two or more methods, and notice that all the dates on the chart show consilience; that is, they agree. Different people, different labs, different methods. I await your detailed reply.Edited by LindaLou, : typo.