If The Andromeda Galaxy Were Visible To The Naked Eye, It Would Be Six Times Larger Than The Moon In The Night Sky.

If The Andromeda Galaxy Were Visible To The Naked Eye, It Would Be Six Times Larger Than The Moon In The Night Sky. 

-Crazy Facts Of Cosmology. 

Of course only the bright central core of Andromeda is visible to the naked eye, the full extent of the Andromeda galaxy in our sky is already about six times that of the Moon. Here is the composite picture that did the rounds on the internet a few years back:

The Moon is about 0.5 degrees across so Andromeda is about six times bigger shows in the picture. It's close enough, and certainly is an  amazing thing to consider. After all, Andromeda is 2.5 million light years away quintillion kilometers.

Andromeda is one of the very few galaxies you can  with your naked eye from a dark side. It's easy in binoculars, and if you use a small telescope,  the galaxy fills the eye piece.

Andromeda has vast spiral arms that extend well out from the core. from Earth, galaxy appears to be more than 3 degrees across.

There are 90 degrees in right angle, and 360 degrees in a circle; astronomers use angular size as a way to measure how big an object is on the sky.