Okay, I have no idea how true this is, but I learned in middle/high school that with each orbit the moon gets further away from the earth and in a couple million years it might get so far away that the earth won’t even have a moon anymore. Which makes me wonder… how stable is Earth’s orbit? Like what’s keeping us from getting too far away and flying off into space? Or is there a possibility of that happening ever? I’m so curious
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As others have pointed out, as things stand the sun is expected to explode before the Earth has a chance to leave it’s natural orbit. That doesn’t mean it can’t leave it’s orbit before then. It would just take an outside force.
A large body like a planet, a star, or even a black hole could in theory pass by us so close that it’s gravity knocks us out of our current orbit. At which point the Earth could become a [rouge planet](https://en.wikipedia.org/wiki/Rogue_planet).
As unlikely as this is, this is believed to be how Uranus became a part of our solar system. When you rewind our planet’s current orbits knowing what we do about physics far back enough, they start to no longer make sense. When you allow the computer model to have Uranus show up later and become captured by the sun’s gravity, they make more sense. That combined with it’s unusual axis tilt, and it’s moon’s orbits, it seems likely it started off as a rouge planet.
As others have pointed out, as things stand the sun is expected to explode before the Earth has a chance to leave it’s natural orbit. That doesn’t mean it can’t leave it’s orbit before then. It would just take an outside force.
A large body like a planet, a star, or even a black hole could in theory pass by us so close that it’s gravity knocks us out of our current orbit. At which point the Earth could become a [rouge planet](https://en.wikipedia.org/wiki/Rogue_planet).
As unlikely as this is, this is believed to be how Uranus became a part of our solar system. When you rewind our planet’s current orbits knowing what we do about physics far back enough, they start to no longer make sense. When you allow the computer model to have Uranus show up later and become captured by the sun’s gravity, they make more sense. That combined with it’s unusual axis tilt, and it’s moon’s orbits, it seems likely it started off as a rouge planet.
As others have pointed out, as things stand the sun is expected to explode before the Earth has a chance to leave it’s natural orbit. That doesn’t mean it can’t leave it’s orbit before then. It would just take an outside force.
A large body like a planet, a star, or even a black hole could in theory pass by us so close that it’s gravity knocks us out of our current orbit. At which point the Earth could become a [rouge planet](https://en.wikipedia.org/wiki/Rogue_planet).
As unlikely as this is, this is believed to be how Uranus became a part of our solar system. When you rewind our planet’s current orbits knowing what we do about physics far back enough, they start to no longer make sense. When you allow the computer model to have Uranus show up later and become captured by the sun’s gravity, they make more sense. That combined with it’s unusual axis tilt, and it’s moon’s orbits, it seems likely it started off as a rouge planet.
The ELI5 answer that as the Moon pulls the tides on Earth, the Tides pushes the Moon away.
This section from a BBC article from 2011 gives a more in-depth explaination:
> Due to the rotation of the Earth, this tidal bulge actually sits slightly ahead of the Moon. Some of the energy of the spinning Earth gets transferred to the tidal bulge via friction.
>This drives the bulge forward, keeping it ahead of the Moon. The tidal bulge feeds a small amount of energy into the Moon, pushing it into a higher orbit like the faster, outside lanes of a test track.
>This phenomenon is similar to the experience one feels on a children’s roundabout. The faster the roundabout spins the stronger the feeling of being slung outwards.
>But the energy gained as the Moon is pushed higher is balanced by a reduction in the energy of its motion – so an acceleration provided by the Earth’s tides is actually slowing the Moon down.
The Moon actually keeps the Earth relatively stable, keeping seasonal variances down to a minimum.
The Earth is moving away from the Sun, just at an inconsequential rate over the lifetime of the Sun. Earth’s orbit might reach 1.01-1.03 AU before it’s engulfed by the Sun.
>with each orbit the moon gets further away from the earth
This is true. Because the Earth rotates faster than the Moon orbits the Earth, the Earth is slowly transferring its rotational energy to the Moon, causing the Earth to slow down and the Moon to orbit faster, very gradually boosting it to a higher and higher orbit.
>and in a couple million years it might get so far away that the earth won’t even have a moon anymore.
This is not true. The Earth does not have enough rotational energy to eject the Moon from orbit. As the Moon gets farther away and the Earth slows down, the rate of energy transfer will slow. Once the Earth is spinning so slowly that it matches the speed of the Moon’s orbit, the energy transfer will stop completely and the Moon will stop moving away. This process will take around fifty *billion* years, ten times longer than the Earth and Moon have existed.
The Earth and Moon have such a large “tidal” interaction because of their relative size and proximity: the Moon has about 1% of the Earth’s mass and is only about thirty Earth-diameters away. On the other hand, the Earth only has 0.0003% of the Sun’s mass and is 107 solar diameters away. The tidal forces accelerating the Earth are negligibly small, and the Sun will kill the Earth in other ways long, *long* before it has a chance to accelerate the Earth’s orbit by any significant amount.
>with each orbit the moon gets further away from the earth
This is true. Because the Earth rotates faster than the Moon orbits the Earth, the Earth is slowly transferring its rotational energy to the Moon, causing the Earth to slow down and the Moon to orbit faster, very gradually boosting it to a higher and higher orbit.
>and in a couple million years it might get so far away that the earth won’t even have a moon anymore.
This is not true. The Earth does not have enough rotational energy to eject the Moon from orbit. As the Moon gets farther away and the Earth slows down, the rate of energy transfer will slow. Once the Earth is spinning so slowly that it matches the speed of the Moon’s orbit, the energy transfer will stop completely and the Moon will stop moving away. This process will take around fifty *billion* years, ten times longer than the Earth and Moon have existed.
The Earth and Moon have such a large “tidal” interaction because of their relative size and proximity: the Moon has about 1% of the Earth’s mass and is only about thirty Earth-diameters away. On the other hand, the Earth only has 0.0003% of the Sun’s mass and is 107 solar diameters away. The tidal forces accelerating the Earth are negligibly small, and the Sun will kill the Earth in other ways long, *long* before it has a chance to accelerate the Earth’s orbit by any significant amount.
The ELI5 answer that as the Moon pulls the tides on Earth, the Tides pushes the Moon away.
This section from a BBC article from 2011 gives a more in-depth explaination:
> Due to the rotation of the Earth, this tidal bulge actually sits slightly ahead of the Moon. Some of the energy of the spinning Earth gets transferred to the tidal bulge via friction.
>This drives the bulge forward, keeping it ahead of the Moon. The tidal bulge feeds a small amount of energy into the Moon, pushing it into a higher orbit like the faster, outside lanes of a test track.
>This phenomenon is similar to the experience one feels on a children’s roundabout. The faster the roundabout spins the stronger the feeling of being slung outwards.
>But the energy gained as the Moon is pushed higher is balanced by a reduction in the energy of its motion – so an acceleration provided by the Earth’s tides is actually slowing the Moon down.
The Moon actually keeps the Earth relatively stable, keeping seasonal variances down to a minimum.
The Earth is moving away from the Sun, just at an inconsequential rate over the lifetime of the Sun. Earth’s orbit might reach 1.01-1.03 AU before it’s engulfed by the Sun.
The ELI5 answer that as the Moon pulls the tides on Earth, the Tides pushes the Moon away.
This section from a BBC article from 2011 gives a more in-depth explaination:
> Due to the rotation of the Earth, this tidal bulge actually sits slightly ahead of the Moon. Some of the energy of the spinning Earth gets transferred to the tidal bulge via friction.
>This drives the bulge forward, keeping it ahead of the Moon. The tidal bulge feeds a small amount of energy into the Moon, pushing it into a higher orbit like the faster, outside lanes of a test track.
>This phenomenon is similar to the experience one feels on a children’s roundabout. The faster the roundabout spins the stronger the feeling of being slung outwards.
>But the energy gained as the Moon is pushed higher is balanced by a reduction in the energy of its motion – so an acceleration provided by the Earth’s tides is actually slowing the Moon down.
The Moon actually keeps the Earth relatively stable, keeping seasonal variances down to a minimum.
The Earth is moving away from the Sun, just at an inconsequential rate over the lifetime of the Sun. Earth’s orbit might reach 1.01-1.03 AU before it’s engulfed by the Sun.
Here’s a great video explainer describing the most likely process by which the earth could be knocked out of orbit:
Here’s a great video explainer describing the most likely process by which the earth could be knocked out of orbit:
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