Deep Sky · 3 of 5
Finding the Andromeda Galaxy
What is the farthest thing most people ever see with their own eyes?
Star-hop from the Great Square to a trillion-star galaxy 2.56 million light-years away — the most distant thing most eyes ever see.
You’ll be able to star-hop from the Great Square to the Andromeda Galaxy.
Before this: Dark Skies, Dark Eyes (6 min)
Where and which night
Working out when this is best placed from where you are…
Where
Kept for this guide only, until you change it here — your map settings, and every other guide, stay as they are.
Print, play outside or present
Scan with a phone's camera, or open
Sources
- HYG stellar database v4.2 — star positions, magnitudes and every separation quoted here
- NASA/IPAC Extragalactic Database — M31 at 785 kpc (2.56 Mly), M33 at 840 kpc (2.74 Mly)
- de Vaucouleurs, RC3 — M31 optical extent 190′ × 60′, i.e. just over three degrees long
- Bortle, "The Bortle Dark-Sky Scale", Sky & Telescope, February 2001
- Hubble, "A spiral nebula as a stellar system, Messier 31", ApJ 69, 103 (1929) — the Cepheid found on the plate of 5–6 October 1923, marked "VAR!"
- Walterbos & Kennicutt, A&A Suppl. 69, 311 (1987) — M31's disc inclined 77° to our line of sight
- van der Marel et al., ApJ 753, 8 (2012) — M31 approaching the Milky Way at 110 km/s
- Clark, Visual Astronomy of the Deep Sky (CUP 1990) — averted vision and the eye's contrast threshold
With a keyboard, focus the sky, aim it with the up and down arrow keys, and press Enter to drop the pin at the centre of the view; or press Show me.