If instead of earth and moon, we had two earths same size could it work?

[RandomPoster]

If there were two earths about the same size far enough away to prevent gravity from rapidly pulling them into each other, and they were orbiting the sun at the same speed in unison, could they support life? How would it affect the tides if both planets were the same size? Would it matter if they were spinning at different speeds, not orbitting at different speeds, simply spinning differently?

 

[Moonglow]

It would not matter cause humans on both planets would have destroyed each other already..

 

[MarathonMike]

If you replace the moon with something 80 times as massive and put it in the same orbit as the Earth instead of a Lunar orbit, yes the tides would change drastically along with lots of other things.

 

[Old Rocks]

Two bodies are in orbit around each other. The earth is moved by the gravity of the moon, but because the Earth so much more massive, it is not apparent to us. Two earth sized objects would be in orbit around each other, a common center of gravity. That common center of gravity lies within the Earth, in the Earth-Moon system. In an Earth-Earth system, it would be outside of both. The distance between them would be the critical factor in how much affect there would be on each.

 

[TheOldSchool]

It would not matter cause humans on both planets would have destroyed each other already..

If Earth 2 avoided a comet, had dinosaurs, and we could go hunt them, that would be badazz

 

[WinterBorn]

The two earths would orbit around the point at which they both exert the same force. As an example, the earth orbits the sun. But not the center of the sun. The balance point between the two is the center of the orbit. But since the sun is so much more massive than the eart, that point is within the boundaries of the sun.

 

[Fort Fun Indiana]

If there were two earths about the same size far enough away to prevent gravity from rapidly pulling them into each other, and they were orbiting the sun at the same speed in unison, could they support life? How would it affect the tides if both planets were the same size? Would it matter if they were spinning at different speeds, not orbitting at different speeds, simply spinning differently?

Two such bodies would become tidally locked with one another. There would no longer be "tides" on either planet, just perpetual high tide on two sides of each planet and low tide on the other two sides of each planet. And weather would change drastically, as there would be no Coriolis Effect on either planet.

Also, should the center of gravity be close to the ecliptic plane, and their mutual orbit near parallel to it, the Sun would be blocked out much of the time during the day on the sides of the planets facing each other. That being the case, much less energy from the Sun would reach either planet than reaches them now, and they would likely both be very cold, compared to our Earth.

 

[WillMunny]

The mutual gravity between them would be strong enough it would probably provoke plenty of volcanic activity on both planets.

 

[Old Rocks]

If there were two earths about the same size far enough away to prevent gravity from rapidly pulling them into each other, and they were orbiting the sun at the same speed in unison, could they support life? How would it affect the tides if both planets were the same size? Would it matter if they were spinning at different speeds, not orbitting at different speeds, simply spinning differently?

Two such bodies would become tidally locked with one another. There would no longer be "tides" on either planet, just perpetual high tide on two sides of each planet and low tide on the other two sides of each planet. And weather would change drastically, as there would be no Coriolis Effect on either planet.

Also, should the center of gravity be close to the ecliptic plane, and their mutual orbit near parallel to it, the Sun would be blocked out much of the time during the day on the sides of the planets facing each other. That being the case, much less energy from the Sun would reach either planet than reaches them now, and they would likely both be very cold, compared to our Earth.

That depends entirely on their distance from each other.

 

[Old Rocks]

The mutual gravity between them would be strong enough it would probably provoke plenty of volcanic activity on both planets.

Again, distance is the critical factor.

 

[Fort Fun Indiana]

If there were two earths about the same size far enough away to prevent gravity from rapidly pulling them into each other, and they were orbiting the sun at the same speed in unison, could they support life? How would it affect the tides if both planets were the same size? Would it matter if they were spinning at different speeds, not orbitting at different speeds, simply spinning differently?

Two such bodies would become tidally locked with one another. There would no longer be "tides" on either planet, just perpetual high tide on two sides of each planet and low tide on the other two sides of each planet. And weather would change drastically, as there would be no Coriolis Effect on either planet.

Also, should the center of gravity be close to the ecliptic plane, and their mutual orbit near parallel to it, the Sun would be blocked out much of the time during the day on the sides of the planets facing each other. That being the case, much less energy from the Sun would reach either planet than reaches them now, and they would likely both be very cold, compared to our Earth.

That depends entirely on their distance from each other.

True. I suppose there is an upper limit to this distance, because of the gravity of the Sun.

 

[WillMunny]

The mutual gravity between them would be strong enough it would probably provoke plenty of volcanic activity on both planets.

Again, distance is the critical factor.

Yes, I know. I was thinking of Jupiter causing Io's volcanic violence by gravity-raping its core.

 

[CrusaderFrank]

It would all come down to which planet had a better handle on their manmade CO2