Earth ex -- moon ?

[JHAQ]

Has any entity theorised about what Earth would be like now IF the moon had never become detached ? I know the moon is essential for how life originated & survived on earth but would the added gravitational field of Earth changed much on its own

[insane_alien]

the earth was lighter before the formation of the moon(assuming the impactor theory is correct) so the gravitational field would have been less not more.

 

but the difference is small enough that it wouldn't have made much difference. if the gravitational field was stronger, atmospheric pressure would be slightly greater and mountains wouldn't be quite as tall and the opposite would be true if the gravitational field was less.

 

thats about it.

[SH3RL0CK]

The moon is about 1/81 the mass of the earth, or 1.23%. ( See http://en.wikipedia.org/wiki/The_moon )

 

As such how much would this tiny bit more mass change things? My guess is that it wouldn't change much at all.

[Sisyphus]

Has any entity theorised about what Earth would be like now IF the moon had never become detached ? I know the moon is essential for how life originated & survived on earth but would the added gravitational field of Earth changed much on its own

 

I don't know if it's really accurate to say the Moon "detached." It is probably the collected debris thrown clear when a roughly Mars-sized (much bigger than the Moon, but quite a bit smaller than the Earth) crashed into the young Earth.

 

Anyway, if you were to add the Moon's mass to the Earth's, gravity here wouldn't increase much. The Moon's mass is only a little more than 1% of the Earth's, and gravity would increase by even less than that proportion, because the Earth's radius would also be larger.

[granpa]

the earth would probably get smaller if more mass was added.

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Has any entity theorised about what Earth would be like now IF the moon had never become detached ? I know the moon is essential for how life originated & survived on earth but would the added gravitational field of Earth changed much on its own

I presume it would be spinning much faster.

[Kyrisch]

This is what I found with a few seconds of google searching. Seems pretty solid, geology-wise, and rather in-depth without going too far (it's a three-page paper).

[insane_alien]

the earth would probably get smaller if more mass was added.

 

only if enough mass was added to turn the earth into degenerate matter.

 

unless you're adding a neutron star or blackhole your not going to make the earth smaller.

[D H]

This is what I found with a few seconds of google searching.

There are many other web articles on the same subject. To the OP: Do a little homework before you ask questions, and ask questions about what you found. Doing so tends to increase the quality of the discourse.

 

Seems pretty solid, geology-wise, and rather in-depth without going too far (it's a three-page paper).

The part about the Earth rotating once per eight hours is not that solid. The Moon has slowed the Earth's rotation rate considerably since the formation of the Moon. The dominant theory is that the Moon formed as a result of the collision of the Earth with some other body. That collision would almost certainly have changed the Earth's angular momentum by a considerable amount. What the Earth's rotation rate was prior to this collision, we do not know.

[Airbrush]

A few years ago the Discovery Channel had a special "If We Had No Moon" or something like that. They speculated that if the massive collision that probably created the Moon had not occurred, the Earth's oceans would be much deeper and there would be little, if any, land above sea level. Had anyone heard that one?

 

Recently I heard on Michio Kaku's radio program "Explorations" that the fact the Moon stabilizes Earth's rotational axis is not as big a factor as previously supposed. If we had no Moon, the Earth's axis would wonder, up to 90 degrees, but major movement would take tens of millions of years and would not be so disasterous to life on Earth.

[VedekPako]

A few years ago the Discovery Channel had a special "If We Had No Moon" or something like that. They speculated that if the massive collision that probably created the Moon had not occurred, the Earth's oceans would be much deeper and there would be little, if any, land above sea level. Had anyone heard that one?

 

 

Yeah, I saw that one. Though, I disagree with it. The early Earth that got hit with the Moon probably had a molten surface. All the water would have been in the atmosphere.

 

I'm just speculating, but the Earth-Moon impact did throw out some of the early atmosphere and water, but some of it would fall back into Earth and it probably had little effect.

 

The accreted solar system probably suffered many impacts that blew of their atmospheres and water.

 

Mars had water. In fact, Mars had more water per ratio than Earth, which could mean that the same number of comets carrying water impacted Mars as they did Earth, since Mars is smaller, it would have more water.

[Blue Fire]

[snip]

Mars had water. In fact, Mars had more water per ratio than Earth, which could mean that the same number of comets carrying water impacted Mars as they did Earth, since Mars is smaller, it would have more water.

Indeed we know Mars had water, and we know it still does have water at least in ice form and probably water vapor (as ice sublimates to vapor), but I'm wondering where you got your information that Mars had More water per ratio than Earth? I did a quick search on this and came up with only vague guestimates and speculation with no definite claim to how much water Mars had in the past. I'd be interested in any further info you could point me to. Edited July 19, 2009 by Blue Fire
typos

[CDizzle]

Now the moon creates waves and light at night. If we had no moon then the ocean, I think, would be very deep and there would be almost no land to live upon. Did God strategically put it there? Or did an asteroid actually hit the earth? Who knows!

[Sisyphus]

Now the moon creates waves and light at night. If we had no moon then the ocean, I think, would be very deep and there would be almost no land to live upon. Did God strategically put it there? Or did an asteroid actually hit the earth? Who knows!

 

So why does God hate Mars?

[VedekPako]

Indeed we know Mars had water, and we know it still does have water at least in ice form and probably water vapor (as ice sublimates to vapor), but I'm wondering where you got your information that Mars had More water per ratio than Earth? I did a quick search on this and came up with only vague guestimates and speculation with no definite claim to how much water Mars had in the past. I'd be interested in any further info you could point me to.

 

It was a book I got from the local library called, Traveler's Guide to Mars or something along that line. It was about Martian geology. It was divided up into three eras and it talked about various geologic formations on Mars.

 

Also, I saw a show on one of the science channels that took all the water off of Earth and put it into a ball and compared it with the size of the Earth. Although water makes a big difference on the surface, it's rather small in comparison with the mass of the Earth. The water was so small, in comparison, that it could have been brought in by cometary impacts and or carried in small amounts in asteroids.

 

I just thought about the Late Heavy Bombardment and how that effected water on Earth and Mars. The movements of Uranus and Neptune that disrupted an Oort cloud would have sent many cometary fragments, mostly water into the Inner Solar System. This could have increased the amount of water on all four worlds and Moon. I supposed we could calculate the amount of impacts on the Moon and estimate the numbers that would have struck Earth and Mars to get an idea how much water was delivered by then.