2837
2838

/r/allAustralia vs Pluto (i.imgur.com)

tfburns が 投稿

並べ替え:
ベスト
トップ新着論争中古い順Q&A
あなたは単独のコメントのスレッドを見ています。

残りのコメントをみる →

[–]Xet [スコア非表示]  (20子コメント)

Incidentally, if Pluto were to just suddenly 'appear' resting on the planet's surface like this, with an initial velocity of 0, what would happen?

I can't imagine it would remain chilling there as a sphere for very long. Would it just instantly collapse, or would it start sinking into the earth? Perhaps a bit of both?

[–]Zophir___ [スコア非表示]  (1子コメント)

You should submit this to Randall Munroe (of XKCD fame) for his What if series.

whatif@xkcd.com

https://what-if.xkcd.com/

[–]Vatnos [スコア非表示]  (2子コメント)

I think it would sink into earth, but due to its sheer mass the first half of the sinking would happen quickly as if it were falling from space at terminal velocity, with the rock+ice being crushed nearly instantly and converted into heat. That explosion would convert Earth's entire crust into magma, boil the oceans into the atmosphere, and destroy 99.999% of all life on Earth.

The power from the explosion would be strong enough to fling some material from the earth's crust into space that would accrete to form a second, smaller moon.

A tiny percentage of bacteria would still survive and evolution would start over on the planet from there. It wouldn't even take that long in geological terms for the planet to cool off and resume as if nothing had happened.

[–]Squid4Hire [スコア非表示]  (0子コメント)

Would it melt enough to be harmless? How long would it take to melt that much? Assuming its as close to the sun as earth is

[–]FamBot [スコア非表示]  (1子コメント)

I don't know for sure but I imagine it would involve a lot of sinking, crushing, crumbling and melting.

I imagine that amount of mass added to earth in one spot would cause some severe instability with the earth's rotation causing a wobble affect which might cause the earth orbit to change significantly. Either throwing us further in to space and thusly to a freezing death or cause us to get even closer to the sun.

The change in orbit could be so abrupt that it causes the moon's orbit to change drastically. Either completely flinging the moon away or causing the moon to whip outward only to be drawn back to earth much more violently possibly colliding with the earth (again) or creating a very oblong orbit in which the moon gets closer and further away as it orbits.

But again I don't know. These are just my guesses.

[–]Hosni__Mubarak [スコア非表示]  (0子コメント)

Or more likely, the combined gravity of the two planets would pull the moon towards earth which would cause the moon to collide with the earth, causing even more chaos.

[–]tfburns[S] [スコア非表示]  (5子コメント)

You'd have to compare the density of Pluto with that of the average surface of Earth's (if we assume it is hovering over a surface like Australia). As there's a lot of ice on Pluto, its density would likely be much less than Earth's surface, and so I'd imagine the impact of it on Australia (for example) would be less catastrophic than if its whole mass was rocky.

Assuming you just magicked Pluto above Australia like in the picture, I'd predict that the ice would crack and crumble down over the hot continent, with the fine ice particles melting and the large shards wreaking havoc. The rocky core might form a new Uluru, but I don't think many people would be able to see it in a great hurry as there would be earthquakes and volcano eruptions (caused by the impact) and flooding (caused by the melting ice), not to mention the crushing and destruction of a large part (or all?) of Australia. Gee ... I really wish this image was of another continent now as I'm Australian!

P.S. All of this is mere speculation, I'm not a physicist.

[–]dittbub [スコア非表示]  (2子コメント)

If Pluto was gently set onto Australia... would you end up with a giant mountain? Or would the destruction be so volatile it would spread matter all over the Earth?

[–]tfburns[S] [スコア非表示]  (1子コメント)

I would imagine it like two balls of that plastic putty stuff kids play with, only with a crustier outside and a more liquid inside. You would end up with extra mass where Australia is, certainly, but the sheer impact would, I think, crack the Australian tectonic plate and probably this would ricochet to other plates which would also crack. I can imagine the modelling to figure out what it would all look like afterwards would be rather intensive/specialised. Perhaps a new plate - the Plutonic tectonic plate - would form at the site of impact, after all the lower layers settle.

[–]MrJAPoe [スコア非表示]  (0子コメント)

"Ice" doesn't inherently mean H2O in this case. A large percentage of Pluto's mass is frozen nitrogen and hydro carbons (methane, I believe)

[–]sprucenoose [スコア非表示]  (3子コメント)

It would crash into Earth at a relatively low velocity, but would certainly distort the very composition of the planet, eject a lot of matter into space, almost instantly wipe out all life on Earth and possibly for all time.

[–]Jahkral [スコア非表示]  (2子コメント)

What, no it wouldn't. It can't crash into earth if its already sitting on the surface! It would sink to a degree and there would be a buttload of volcanism and then a lot of stuff would slowly die over time. It would probably take thousands of years if not longer for pluto to really fuse with earth.

I think the more notable effects would be the sudden change in center of gravity, rotational dynamics etc. New wind patterns and day lengths will probably kill a lot more life than the incredibly slow fusion of the planets.

[–]sprucenoose [スコア非表示]  (1子コメント)

It would not be "sitting" on the surface. What keeps the planets together is their gravity. Here, there would be two massive gravitational points pulling towards each other, and the enter of gravity would be somewhere in between, towards which they would both be pulled. Both bodies would be torn apart as they accelerated toward it, but Pluto, being the smaller body, even more so. It would just, essentially, fall apart and crash into the distorted Earth to create one large planet.

[–]Jahkral [スコア非表示]  (0子コメント)

It would START on the surface. Obviously there is a pull of the centers to eachother, but it would not just suddenly start hurtling. We're talking about thousands of kilometer of extremely dense rock. The compression would be slow (there would be a notable immediate compression as the weaker overlying layers crush, but I don't want to speculate on the global impact of that) by human standards.

[–]hamboi [スコア非表示]  (0子コメント)

Gonna submit this to askscience later, if no one else does

[–]Sylvester_Scott [スコア非表示]  (0子コメント)

Zaphod Beeblebrox would have a lot of explaining to do.

[–]architta [スコア非表示]  (0子コメント)

Velocity of 0 relative to the earth or space? If its 0 relative to the earths velocity impact will be less. If it is relative to space... Its a collision