What is the motion btwn Milky Way & Andromeda relative to the motion btwn those two and the Great Attractor?

Submitted by Griegz t3_11ug41g in askscience

The Milky Way is moving toward the Great Attractor. Andromeda is moving toward the Great Attractor. Andromeda and the Milky Way are moving toward each other.

Is the Milky Way between Andromeda and the GA, and Andromeda is moving toward the GA faster? Andromeda between the Milky Way and the GA, Milky Way moving faster? Or is the collision vector of the two galaxies more perpendicular to their movement toward the GA?

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Ravenson420 t1_jco3vsb wrote

The Great Attractor is somewhere in the Vela/Norma/Centaurus region, which is pretty much opposite the Andromeda constellation. As such, the Milky Way is mostly in between Andromeda and the GA. Thus, the collision vectors of the two galaxies is mostly, "Andromeda is moving toward the GA faster".

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OneAndOnlyJoeseki t1_jcrsve8 wrote

That doesn’t sound right, if Andromeda and milky way are heading towards each other, and the great attractor is on the far side of Andromeda. Doesn’t that mean the milky way is headed toward the GA faster than andromeda is. It may be closer but the MW is narrowing that gap

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davesoverhere t1_jcsbqzb wrote

You have it backwards. The Vela region is opposite Andromeda from our reference point, so we’re in between the two.

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Ravenson420 t1_jcrywyq wrote

No because if the Milky Way were going faster than Andromeda they'd never collide.

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OneAndOnlyJoeseki t1_jctx3lh wrote

Your description of opposite has to be wrong then

MW — And— GA. Milky way is moving toward Ga Faster than And

MW - GA — And Something is very wrong with this scenario

And - MW - GA. And is moving faster than MwW

And - GA - MW. Again something very wrong with-physics in tuis scenario

Which is it?

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Ravenson420 t1_jcuh5qw wrote

It's the third. I said right in the post that the Milky Way is between Andromeda and the Attractor because those two things are in basically opposite parts of the sky.

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