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# If the moon's orbit was far more elliptical

#### Fort Fun Indiana

##### Diamond Member
except the environment we live in is extremely hospitable to the potential for life to evolve and fine-tune itself.
Except for when it isn't, such as during the early Bombardment, or when the asteroid that killed the dinosaurs set the sky on fire. Another large impact could end the age of land mammals.

#### james bond

##### Gold Member
That's absurd.
Only to a foolish astronomer who can't do math. We know the moon is moving away about 1 1/2" or 3.8 cm every year from NASA data. If we start with the moon touching the Earth, then it would take about 1.5 billion years to get to where it is now. Thus, you got about 3 billion years difference from the current age of the moon which means your calculation of the age of the moon is wrong..

#### james bond

##### Gold Member
That rate isn't, nor has it ever has been, constant. When the moon first formed, it was much closer to the earth. As the earth and moon cooled and solidified, the orbits became more stable.
See post #42. It has been constant. Even if it wasn't, how do you get a difference of 3 billion years?

Here's what I read, "The Moon's orbit (its circular path around the Earth) is indeed getting larger, at a rate of about 3.8 centimeters per year. (The Moon's orbit has a radius of 384,000 km.) I wouldn't say that the Moon is getting closer to the Sun, specifically, though--it is getting farther from the Earth, so, when it's in the part of its orbit closest to the Sun, it's closer, but when it's in the part of its orbit farthest from the Sun, it's farther away.

The reason for the increase is that the Moon raises tides on the Earth. Because the side of the Earth that faces the Moon is closer, it feels a stronger pull of gravity than the center of the Earth. Similarly, the part of the Earth facing away from the Moon feels less gravity than the center of the Earth. This effect stretches the Earth a bit, making it a little bit oblong. We call the parts that stick out "tidal bulges." The actual solid body of the Earth is distorted a few centimeters, but the most noticable effect is the tides raised on the ocean.

Now, all mass exerts a gravitational force, and the tidal bulges on the Earth exert a gravitational pull on the Moon. Because the Earth rotates faster (once every 24 hours) than the Moon orbits (once every 27.3 days) the bulge tries to "speed up" the Moon, and pull it ahead in its orbit. The Moon is also pulling back on the tidal bulge of the Earth, slowing the Earth's rotation. Tidal friction, caused by the movement of the tidal bulge around the Earth, takes energy out of the Earth and puts it into the Moon's orbit, making the Moon's orbit bigger (but, a bit pardoxically, the Moon actually moves slower!).

The Earth's rotation is slowing down because of this. One hundred years from now, the day will be 2 milliseconds longer than it is now.

This same process took place billions of years ago--but the Moon was slowed down by the tides raised on it by the Earth. That's why the Moon always keeps the same face pointed toward the Earth. Because the Earth is so much larger than the Moon, this process, called tidal locking, took place very quickly, in a few tens of millions of years.

#### james bond

##### Gold Member
We are "fine tuned" to the environment in which we evolved. That environment is on Earth's surface.
Lol, you're the one trolling. That's not what fine tuning is. It's the Earth that is fine tuned as an environment hospitable to life. We know from the fine tuning parameters. I'll bet you \$100 that we can't survive anywhere else by 2025. NASA thinks we'll be on Mars by then.

#### daveman

##### Diamond Member
If the moon orbited the earth more like this, with the moon at times getting within perhaps 1,500 miles from the earth and at times getting several million miles away, could we survive? A full moon would be a sight to look forward to.

Couldn't happen. The moon would be destroyed by tidal forces if it comes within the Roche Limit, which for the Earth-moon pair is 9,484 kilometers or 5,983 miles.

Then the Earth would have a ring...which would be way, WAY cooler.

#### Fort Fun Indiana

##### Diamond Member
We know the moon is moving away about 1 1/2" or 3.8 cm every year from NASA data. If we start with the moon touching the Earth, then it would take about 1.5 billion years to get to where it is now. Thus, you got about 3 billion years
Which tells us the rate of retreat was not constant

Are you saying dumb shit on purpose, or are these honest, stupid mistakes you are making?

#### Fort Fun Indiana

##### Diamond Member
That's not what fine tuning is. It's the Earth that is fine tuned as an environment hospitable to life.
False. The life that evolved on earth is fune tuned to it. Obviously.

OP

#### RandomPoster

##### Gold Member
That's absurd.
Only to a foolish astronomer who can't do math. We know the moon is moving away about 1 1/2" or 3.8 cm every year from NASA data. If we start with the moon touching the Earth, then it would take about 1.5 billion years to get to where it is now. Thus, you got about 3 billion years difference from the current age of the moon which means your calculation of the age of the moon is wrong..
Unless the rate is not constant. I honestly don't know, I'm only guessing that as the distance between the earth and the moon increases, the gravitational pull preventing the moon from drifting away from the earth may diminish and result in the rate increasing slowly over time. Perhaps someone more knowledgeable might be able to clarify, except I wasn't able to find anything on the internet to verify this one way or the other.

#### james bond

##### Gold Member
If the moon orbited the earth more like this, with the moon at times getting within perhaps 1,500 miles from the earth and at times getting several million miles away, could we survive? A full moon would be a sight to look forward to.

Couldn't happen. The moon would be destroyed by tidal forces if it comes within the Roche Limit, which for the Earth-moon pair is 9,484 kilometers or 5,983 miles.

Then the Earth would have a ring...which would be way, WAY cooler.
That's right. I forgot about that. It also explains why we wouldn't be pulled apart as the Roche limit only applies to gravitationally bound objects.

#### james bond

##### Gold Member
Which tells us the rate of retreat was not constant

The life that evolved on earth is fune tuned to it. Obviously.
What parameters do we have to make us fine tuned to Earth? Does that make us not be able to live elsewhere? Just what are you claiming with this fine tuning? NASA thinks we can live on Mars even though we cannot colonize it. We cannot colonize the moon.

#### Fort Fun Indiana

##### Diamond Member
Which tells us the rate of retreat was not constant

The life that evolved on earth is fune tuned to it. Obviously.
What parameters do we have to make us fine tuned to Earth? Does that make us not be able to live elsewhere? Just what are you claiming with this fine tuning? NASA thinks we can live on Mars even though we cannot colonize it. We cannot colonize the moon.
I dont have to prove the rate is not contact. We know how old the earth and moon are. You are saying that is false. The burden of proof lies with you.

What parameters do we have to make us fine tuned to Earth?
Every trait we possess, of course. In a difgerent environment, under different selective pressures, we would have evolved differently.

This is obvious to everyone, except for people who reject evolution due to religion. And I have zero interest in being an audience for your idiotic evolution denial diatribe.

#### daveman

##### Diamond Member
If the moon orbited the earth more like this, with the moon at times getting within perhaps 1,500 miles from the earth and at times getting several million miles away, could we survive? A full moon would be a sight to look forward to.

Couldn't happen. The moon would be destroyed by tidal forces if it comes within the Roche Limit, which for the Earth-moon pair is 9,484 kilometers or 5,983 miles.

Then the Earth would have a ring...which would be way, WAY cooler.
That's right. I forgot about that. It also explains why we wouldn't be pulled apart as the Roche limit only applies to gravitationally bound objects.
Ron Miller shows what an Earth ring would look like.

#### daveman

##### Diamond Member
We cannot colonize the moon.
We can, but it'll take a shitload of engineering.

#### james bond

##### Gold Member
Unless the rate is not constant. I honestly don't know, I'm only guessing that as the distance between the earth and the moon increases, the gravitational pull preventing the moon from drifting away from the earth may diminish and result in the rate increasing slowly over time. Perhaps someone more knowledgeable might be able to clarify, except I wasn't able to find anything on the internet to verify this one way or the other.
I was using three links -- Is the Moon moving away from the Earth? When was this discovered? (Intermediate) - Curious About Astronomy? Ask an Astronomer, The moon's recession and age - creation.com, and https://www.quora.com/What-is-Roche-limit. NASA has changed since Trump took over and got rid of Obama's head of NASA who wanted to go to Mars to show life.

#### james bond

##### Gold Member
We cannot colonize the moon.
We can, but it'll take a shitload of engineering.
I used to think that, but to colonize any planet or moon, I've heard the secular scientists think we have to send 50,000 people there.

#### daveman

##### Diamond Member
We cannot colonize the moon.
We can, but it'll take a shitload of engineering.
I used to think that, but to colonize any planet or moon, I've heard the secular scientists think we have to send 50,000 people there.
Somebody's gotta go to build the place, right?

We have to get off this one single rock.

#### ReinyDays

##### Silver Member
Couldn't happen. The moon would be destroyed by tidal forces if it comes within the Roche Limit, which for the Earth-moon pair is 9,484 kilometers or 5,983 miles.
Then the Earth would have a ring...which would be way, WAY cooler.
I'm curious if the Moon would remain in such a high elliptical orbit ... or would there be circularization forces? ... the Moon swinging out to periapsis is one thing, swinging the Earth out to her periapsis is another ... both objects would be much further distant from the barycenter for most of the time ... perhaps there exists some mysterious "momentum" exchange that causes the orbits to become more circular? ...

The Moon shattered in Cowboy Bebop rendering life on Earth quite hazardous ... maybe not so cool? ...

#### james bond

##### Gold Member
He's not an astronmer, but a space artist lol. The Earth could've had a ring before, but I rather have the moon. Once the Roche limit breaks a satellite up, then it can't be put back together again.

#### james bond

##### Gold Member
I dont have to prove the rate is not contact. We know how old the earth and moon are. You are saying that is false. The burden of proof lies with you.
I've proved the Earth is 6K years old from creation.com which you claimed I used. It's a nice source, but biased so I used other sites. Per the Roche limit, you have to start there and with the lunar recession, the estimate of the moon being 4.5 B yrs old cannot be right. AFAIK the recession has been constant -- Is the Moon moving away from the Earth? When was this discovered? (Intermediate) - Curious About Astronomy? Ask an Astronomer. You should know this since you're the guy with a telescope and camera setup lol.

Every trait we possess, of course. In a difgerent environment, under different selective pressures, we would have evolved differently.
Lol, lol, lol. These are just your assertions. Nothing I can use here.

If this is it, then you need to take your telescope and camera and run along kiddie.

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