Galaxies
Galaxies#
In 1929, Edwin Hubble discovered another galaxy. Until then it was though this galaxy was the sole galaxy.
A light year - the distance light travels in a year - 9.5 trillion kms.
earth is 25_000 light years away from the centre of the galaxy.
The milky way is 100_000 light years across.
Andromeda, out closest neighbour, is 200_000 lightyears across.
M87, larger elliptical galaxy.
IC-10-11 is 6_000_000 light years across.
Gravity makes stars.
The first stars formed 200 million years after the big bang.
Then gravity pulled them together forming galaxies.
The Hubble space telescope can see the earliest galaxies of all, formed 1 billion years after the formation of the universe. THat is the max the Hubble can see.
Super massive black holes are at the centre of many galaxies.
quasar - when black holes devour too quickly - what they are consuming is discharged back into space as energy.
In astronomy, an aeon is defined as a billion years AE.
In Buddhism, an “aeon” or mahakalpa (Sanskrit: महाकल्प) is often said to be 1_334_240_000 years, the life cycle of the world.
Dark matter is apparently keeping the galaxy from expanding out.
In a computer simulation the gravity was not strong enough to keep the galaxy together. Adding virtual dark matter gravity held the galaxy together.
Clumpings of dark matter created galaxies.