Astronomy Picture of the Day 10-21-02

NASA ^ | 10-21-02 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2002 October 21

M31: The Andromeda Galaxy
Credit & Copyright: Robert Gendler

Explanation: Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two million years for light to reach us from there. Although visible without aide, the above image of M31 is a digital mosaic of 20 frames taken with a small telescope. Much about M31 remains unknown, including how the center acquired two nuclei.

[petuniasevan]

Astronomy Fun Fact:

M31, the Andromeda Galaxy, is the nearest spiral to our own. It is the most distant object visible to the naked eye.
(Very dark skies required!) Distance: 2.2 Mega (million) light years.

Southwest part of M31 from Subaru Telescope

Hubble image of M31's double nucleus

M31 and Comet Ikeya-Zhang 4-5-02

[petuniasevan]

[Savage Beast]

Those photographs are beautiful, PS.

[RightWhale]

M31 is close, and getting closer. It will be here soon enough, and if we are still stuck on this mudball, we could be in deep trouble.

[Joan912]

Gorgeous!