Jump to content

DRAGONMOUNT

A WHEEL OF TIME COMMUNITY

If the planets were as close to the Earth as the Moon is (was?)


Elgee

Recommended Posts

I think we'd be squished but ya pretty

 

 If the centers of these planets were as close as the moon's center is, yes we would be.

 

 

If the surface was as close as the moon's surface is, then we'd be fine (but for half of the planets we would become the moon :P and for Mars we'd possibly become a dual planet in which case we'd no longer be a planet because a planet by definition has cleared everything of like size out of our orbit <--this is the real reason pluto is no longer a planet. One of its moons is almost as big as it is and they actually orbit each other as they orbit the sun. Ok, science lesson over--Once an astronomy instructor, always an astronomy instructor! ;P )

Link to comment
Share on other sites

If it were a sudden change it would probably set us into a round of havoc. If it had always been that way, things would be different but it's possible we'd still be more or less what we are now. I can't say that with enough certainty, but I can ask a higher authority on the subject if you are interested? :P 

Link to comment
Share on other sites

Gosh, astronomy is my favorite subject. Thank you for the lesson, actually, those things are the best~!

 

Wouldn't that make Pluto and its moon both planets, then, if they are just two planets orbiting one another? Or, dual planet, as you say?

Link to comment
Share on other sites

I asked him about Jupiter in particular since that would be the most extreme example. In that instance, there is the automatic change that we would be a moon of Jupiter because that's just war would be the case in that situation. Here was his answer:

"If we were a close moon of Jupiter, what would happen?"

 

 

I can't think of anything dramatic. Except if there are multiple moons. For instance the three-way tug of war between Jupiter and the other moons keep Europa and Io hot in their interior. But the Earth is already hot in the interior, so I imagine if we orbited Jupiter then that would be even worse and we would have world wide volcanoes. Jupiters magnetosphere would make electronics interesting, but we would have developed that technology within that context so who knows. Tides would definitely be larger. Oh! And the Earth would be tidally locked, so a "day" on the Earth would be the orbital period of the earth around Jupiter. For reference, io and Europa are on about 3 and 7 day orbits around Jupiter.

 

So there's that answer :)

 

Fun story--Saturn's rings are actually the rubble of what should have been its moons. If memory serves, the reason they never fully formed is because of Jupiter's pull on them, so Saturn and Jupiter basically had a tug of war and it ended up in the rings. A similar tug of war between Jupiter and the sun is what caused the Asteroid belt--that "should" have been another planet, though we do have the dwarf planet Ceres in there.

 

Which leads me to Aniere's question

 

Wouldn't that make Pluto and its moon both planets, then, if they are just two planets orbiting one another? Or, dual planet, as you say?

 

Here are the three laws that classify something as a full fledged planet:

1. They are large enough that their own gravity causes them to be round

2. Orbits the sun/is not a moon (some of Jupiter's moons would be planets if only they orbited the sun instead)

3. Has cleared anything of like size in its orbit.

 

Dwarf planets are items that were close to planet-hood but did not fulfill all three criteria.

So, in the case of Pluto:

1. It is large enough that gravity makes it round.

2. The second law is arguable both ways. It is the bigger object, and it primarily orbits the sun.

However, its biggest moon, Charon, is big enough that it causes Pluto to "wobble" significantly; it's the difference between you spinning around a small child (where the child is basically spinning around you but you still lean back a bit to account for the weight) and you spinning around with someone who is nearly your size (where you're both spinning around a point in between you). Earth actually wobbles because of the moon, but it's like the spinning a child situation, where Pluto and Charon are two like sized objects. So arguably it's orbiting Charon in addition to orbiting the sun.

3. The third law is the one that definitely makes Pluto a dwarf planet, and it is also because of Charon. Because Charon is big enough that it greatly affects how Pluto orbits and causes it to wobble, it is considered to be a "like sized" object even though it's about half of Pluto's size. 

Link to comment
Share on other sites

Very interesting… I'm wondering if these classifications would be changed if there were planets the size of the gas giants locked in that sort of plutonian struggle.  I know that's probably very unlikely, but it seems like it could have happened under the right circumstances. 

Link to comment
Share on other sites

I asked him about Jupiter in particular since that would be the most extreme example. In that instance, there is the automatic change that we would be a moon of Jupiter because that's just war would be the case in that situation. Here was his answer:

"If we were a close moon of Jupiter, what would happen?"

 

 

 

I can't think of anything dramatic. Except if there are multiple moons. For instance the three-way tug of war between Jupiter and the other moons keep Europa and Io hot in their interior. But the Earth is already hot in the interior, so I imagine if we orbited Jupiter then that would be even worse and we would have world wide volcanoes. Jupiters magnetosphere would make electronics interesting, but we would have developed that technology within that context so who knows. Tides would definitely be larger. Oh! And the Earth would be tidally locked, so a "day" on the Earth would be the orbital period of the earth around Jupiter. For reference, io and Europa are on about 3 and 7 day orbits around Jupiter.

So there's that answer :)

 

Fun story--Saturn's rings are actually the rubble of what should have been its moons. If memory serves, the reason they never fully formed is because of Jupiter's pull on them, so Saturn and Jupiter basically had a tug of war and it ended up in the rings. A similar tug of war between Jupiter and the sun is what caused the Asteroid belt--that "should" have been another planet, though we do have the dwarf planet Ceres in there.

 

Which leads me to Aniere's question

 

Wouldn't that make Pluto and its moon both planets, then, if they are just two planets orbiting one another? Or, dual planet, as you say?

 

Here are the three laws that classify something as a full fledged planet:

1. They are large enough that their own gravity causes them to be round

2. Orbits the sun/is not a moon (some of Jupiter's moons would be planets if only they orbited the sun instead)

3. Has cleared anything of like size in its orbit.

 

Dwarf planets are items that were close to planet-hood but did not fulfill all three criteria.

So, in the case of Pluto:

1. It is large enough that gravity makes it round.

2. The second law is arguable both ways. It is the bigger object, and it primarily orbits the sun.

However, its biggest moon, Charon, is big enough that it causes Pluto to "wobble" significantly; it's the difference between you spinning around a small child (where the child is basically spinning around you but you still lean back a bit to account for the weight) and you spinning around with someone who is nearly your size (where you're both spinning around a point in between you). Earth actually wobbles because of the moon, but it's like the spinning a child situation, where Pluto and Charon are two like sized objects. So arguably it's orbiting Charon in addition to orbiting the sun.

3. The third law is the one that definitely makes Pluto a dwarf planet, and it is also because of Charon. Because Charon is big enough that it greatly affects how Pluto orbits and causes it to wobble, it is considered to be a "like sized" object even though it's about half of Pluto's size.

 

Not sure who your source is (*edit* just noticed he mentions a lot of the same points I do so I guess I only disagree with his conclusion not his theory of events, sorry for not reading more carefully) and don't mean to sound rude but I don't think the earth would survive being 240,000 miles from a planet the size of Jupiter. Gravity is affected by mass, meaning the larger the planet, the stronger it's gravity field, hence Jupiter has the strongest gravitational pull of any planet in our solar system by far. Being so close to it would wreck our tidal systems and not just that but even affect the geo-tectonic plates of the earths crust, causing earthquakes and volcanos with much greater consistency and force than we currently see.

 

Of course, we would also become a moon of Jupiter- not the other way around. And we would have to maintain an incredibly fast orbit to of such a large entity to keep an even telemetry within its gravitational field and not eventually be pulled into the planet itself.

 

On top of that we have to consider that Jupiter has four moons of its own (I know this because I was looking at it with a 1000x telescope last night, was very pretty! you could even see the banding going across it) so there would possibly be issues with overlapping orbits etc. Also consider the radiation Jupiter throws out, remember only earth is a habitable planet in our solar system.

 

Last but not least, for this to happen- would Jupiter come to us or would we go to it? Because that would have a vast effect in terms of the temperature hitting either planet as opposed to now, or the level of light that the earth would get from the sun should we go there... Not to mention (possibly?) the effect of the gravitational pull of the sun on a much larger object such as Jupiter being much closer to it. I'm just guessing at this point.

 

In fact all of that is off the top of my head and could be looked into further and possibly I could be corrected. But all the elements of the solar system are placed exactly where they ought to be for earth to be able to sustain life as we know it.

 

Here's a bonus photo of our moon I took last night with the telescope I mentioned above.

 

aa8c948248bfbbd361b2f7d8cc597f31_zps346b

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...