Putting the moon in Nairobi about 1 billion years ago. :chuckle:
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Scientists Question Darwinism
- Thread starter Jerry Shugart
- Start date
(Barbarian notes the moon receding over Billions of years)
If you assume the rate was uniform over that time, it would be . But as you learned, it's not. Read it again, and think about it carefully. I'm pretty sure you can figure out how you messed up.
Read the links, too. It can help.
If you assume the rate was uniform over that time, it would be . But as you learned, it's not. Read it again, and think about it carefully. I'm pretty sure you can figure out how you messed up.
Read the links, too. It can help.
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Barbarian asserts, sans evidence, that the moon has receded over billions of years.
You forgot how gravity works, right? The closer it is, the better it works. Think about it carefully. I'm pretty sure you can figure out how you messed up.
It isn't. The moon was receding faster in the past and the effect is wearing off as time goes on. :chuckle:
You forgot how gravity works, right? The closer it is, the better it works. Think about it carefully. I'm pretty sure you can figure out how you messed up.
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Watch, now Barbarian is going to say that the continents lined up carefully to slow the moon's departure. :chuckle:
It's like he totally forgets all the times we've explained all this to him. :chuckle:
Then he just gets flustered and angry before he starts lashing out. :chuckle:
It's like he totally forgets all the times we've explained all this to him. :chuckle:
Then he just gets flustered and angry before he starts lashing out. :chuckle:
Tidal rhytmites left a record of that. And yes, it has receded over that time. But it's not constant, because the tidal forces that transfer energy from the Earth to the Moon vary with the coastlines of continents.
This paleontological evidence comes in the form of tidal rhythmites, also known as tidally laminated sediments. Rhythmites have been subjected to intense scrutiny over the last decade or so, and have returned strong results. Williams (1990) reports that 650 million years ago, the lunar rate of retreat was 1.95±0.29 cm/year, and that over the period from 2.5 billion to 650 million years ago, the mean recession rate was 1.27 cm/year. Williams reanalyzed the same data set later (Williams, 1997), showing a mean recession rate of 2.16 cm/year in the period between now and 650 million years ago. That these kinds of data are reliable is demonstrated by Archer (1996). There is also a very good review of the earlier paleontological evidence by Lambeck (1980, chapter 11, paleorotation)
Slichter, Louis B.
Secular Effects of Tidal Friction upon the Earth's Rotation
Journal of Geophysical Research 68(14), July 15, 1963
Actually, as you see, it was usually slower, but it varied over time. Average rate was a little more than half the current rate. It isn't gravity pushing the moon outward. It's the tranfer of kinetic energy from the Earth's rotation, to the moon, as a result of the Moon's tidal drag on the oceans:
(best illustration, worst typo)
In fact, it's much faster than usual now, due to the fragmentation of continents, increasing area of coasts.
You forgot how gravity works; it doesn't push an orbiting body outward. It pulls it inward. The body orbits because the vector of gravity pulling it toward the planet precisely matches the vector moving it forward.
The added energy gained by the Moon (by tidal forces slowing the Earth's rotation) moves it away. The farther out the Moon goes, it gains potential energy (because it takes work to move it to a higher orbit).
BTW, the moon averages about 384,400 km from Earth. Which would be 38,440,000,000 centimeters. At 4 centimeters per year, that would mean 9,610,000,000 years to get to Nairobi, which would be before the solar system formed.
At the actual average, it would be much longer. The actual rate couldn't be much great, because the limiting factor is the amount of energy that can be obtained by tidal forces on the oceans. The mass of the oceans is much less than the mass of the Moon. So it's not going to be feasible to move it that far in a hundred million years as you supposed. By about 2 orders of magnitude.
Yes, please. With citations to the scientific literature
Tidal rhytmites left a record of that. And yes, it has receded over that time. But it's not constant, because the tidal forces that transfer energy from the Earth to the Moon vary with the coastlines of continents.
This paleontological evidence comes in the form of tidal rhythmites, also known as tidally laminated sediments. Rhythmites have been subjected to intense scrutiny over the last decade or so, and have returned strong results. Williams (1990) reports that 650 million years ago, the lunar rate of retreat was 1.95±0.29 cm/year, and that over the period from 2.5 billion to 650 million years ago, the mean recession rate was 1.27 cm/year. Williams reanalyzed the same data set later (Williams, 1997), showing a mean recession rate of 2.16 cm/year in the period between now and 650 million years ago. That these kinds of data are reliable is demonstrated by Archer (1996). There is also a very good review of the earlier paleontological evidence by Lambeck (1980, chapter 11, paleorotation)
Slichter, Louis B.
Secular Effects of Tidal Friction upon the Earth's Rotation
Journal of Geophysical Research 68(14), July 15, 1963
Actually, as you see, it was usually slower, but it varied over time. Average rate was a little more than half the current rate. It isn't gravity pushing the moon outward. It's the tranfer of kinetic energy from the Earth's rotation, to the moon, as a result of the Moon's tidal drag on the oceans:
(best illustration, worst typo)
In fact, it's much faster than usual now, due to the fragmentation of continents, increasing area of coasts.
You forgot how gravity works; it doesn't push an orbiting body outward. It pulls it inward. The body orbits because the vector of gravity pulling it toward the planet precisely matches the vector moving it forward.
The added energy gained by the Moon (by tidal forces slowing the Earth's rotation) moves it away. The farther out the Moon goes, it gains potential energy (because it takes work to move it to a higher orbit).
BTW, the moon averages about 384,400 km from Earth. Which would be 38,440,000,000 centimeters. At 4 centimeters per year, that would mean 9,610,000,000 years to get to Nairobi, which would be before the solar system formed.
At the actual average, it would be much longer. The actual rate couldn't be much great, because the limiting factor is the amount of energy that can be obtained by tidal forces on the oceans. The mass of the oceans is much less than the mass of the Moon. So it's not going to be feasible to move it that far in a hundred million years as you supposed. By about 2 orders of magnitude.
Please dont confuse Stripey with numbers, especially those big ones. Once you get past 6, maybe 7 for his deity's restday, he has trouble.
Tidal friction, in astronomy, strain produced in a celestial body (such as the Earth or Moon) that undergoes cyclic variations in gravitational attraction as it orbits, or is orbited by, a second body. Friction occurs between water tides and sea bottoms, particularly where the sea is relatively shallow, or between parts of the solid crust of planet or satellite that move against each other. Tidal friction on the Earth prevents the tidal bulge, which is raised in Earth’s seas and crust by the Moon’s pull, from staying directly under the Moon. Instead, the bulge is carried out from directly under the Moon by the rotation of the Earth, which spins almost 30 times for every time the Moon revolves in its orbit. The mutual attraction between the Moon and the material in the bulge tends to accelerate the Moon in its orbit, thereby moving the Moon farther from Earth by about three centimetres (1.2 inches) per year, and to slow Earth’s daily rotation by a small fraction of a second per year.
https://www.britannica.com/science/tidal-friction
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I asked a question to you. I was not responding to him.
You have all kinds of understanding problems.
Arthur Brain
Well-known member
I've never seen Barb get flustered and angry about anything and he's certainly never lashed out at anyone. It's his very calmness and reasonable responses that really seem to wind up some of you fundamentalists which is a bit more than ironic. Did you have to chuckle at yourself three times in order to convince yourself?
I mean, you're just the poster bearer for never going off the deep end, eh Stripe?
:dizzy:
Arthur Brain
Well-known member
Apparently you don't cos AIG is an absolute joke. Well, at least it is to those who can think outside of fundamentalist tripe anyway...
ok doser
lifeguard at the cement pond
artie, maybe you'd be happier at a site that's not owned and run by Christian fundamentalists
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We put the FUN in FUNdamentalism!
Don't atheists know that they are fundamentalists of the worst kind?
Arthur Brain
Well-known member
Reminds me of a Simpsons episode...
Arthur Brain
Well-known member
All depends on who and why. Richard Dawkins is an expert on evolutionary biology and quite the humanitarian but his hardcore atheistic stance and fumbling forays into belief and addressing/criticizing that are amateurish and annoying for certain. Otherwise, there's plenty an atheist or "non believer" be it agnostic et al who are hardly hardline about it.
ok doser
lifeguard at the cement pond
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The Simpsons seems about your speed. Probably where you learn about science.
Arthur Brain
Well-known member
Hardly but I do appreciate some of the satire where it comes to religious fundamentalism.
Yes: "his hardcore atheistic stance and fumbling forays into belief and addressing/criticizing that are amateurish and annoying for certain"
He was the one who called Mother Theresa a fascist, right?