Andromeda (M31)
Our galactic twin, closing in
The nearest major spiral galaxy, 2.5 million light-years away. It's heading toward us at 110 km/s and will eventually merge with the Milky Way.
Image: Adam Evans
Vital statistics
Type
Barred Spiral
Distance
2.537 million light-years
Diameter
~220,000 light-years
Stars
~1 trillion
Approach speed
110 km/s
Did you know
Visible to the naked eye as a faint smudge.
Fact 01
The merger will form a new galaxy nicknamed 'Milkomeda'.
Fact 02
Has at least 14 satellite galaxies.
Fact 03
Research & publications
Jump straight into peer-reviewed papers, preprints and authoritative references for Andromeda (M31).
arXiv (preprints)
Open-access preprints in physics & astrophysics.
NASA ADS
The definitive bibliographic database for astronomy.
Google Scholar
Cross-publisher academic search.
Nature
Peer-reviewed articles in Nature & sister journals.
Wikipedia
Encyclopedic overview & onward references.
Tip: ask the Research AI for a curated reading list → /research
