This week’s #MessierMonday is the Milky Way’s nearest neighbour, Andromeda! Also known as M31 and NGC 224.
(1/5)

Photo Credit: J. Randall Owens ( @GhiaPix) aka MY HUSBAND! 😍
Before 1917 M31 was thought to be a nebula in OUR galaxy. It wasn’t until 1923 that it was proven to be another galaxy by Edwin Hubble establishing the intergalactic distance between Andromeda and the Milky Way.

So it’s been known to be a galaxy for less than 100 years!
(2/5)
You’ve probably heard about how the Milky Way and Andromeda are going to collide. This is true but #DontPanic.

Firstly, it isn’t going to happen for literally billions of years.

But more importantly . . .
. . . collisions of galaxies aren’t what you might be imagining💥. The chances of actual stars colliding are practically nil.
P(⭐️⭐️->💥 ) = 0

You see, in space things are REALLY far apart!
(4/5)
That doesn’t mean nothing interesting will happen!

Star systems could be ejected due to the collision — although as far as they’re concerned nothing will be different. Zoom out and speed up time to see the beautiful galactic dance that is a merger.

https://svs.gsfc.nasa.gov/30955 
(5/5)
You can follow @DrMathsPhysics.
Tip: mention @twtextapp on a Twitter thread with the keyword “unroll” to get a link to it.

Latest Threads Unrolled: