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Uncommon galaxy 33 EP

NGC 3931

RA 177.8060° · Dec 52.0009° · openngc

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Score breakdown

· 5 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Galaxy +14
  • Outside our galaxy entirely +6
  • Lenticular galaxy (a disc with no arms) +6
  • Never sets (northern circumpolar) +4
  • Faint fuzzy (mag > 13) +3
Total score 33

1 more point to reach Rare.

Badges

  • Galaxy · +14
  • Outside our galaxy entirely · +6
  • Lenticular galaxy (a disc with no arms) · +6
  • Never sets (northern circumpolar) · +4
  • Faint fuzzy (mag > 13) · +3

Trivia

What it actually is

  • What it actually is. A galaxy: a gravitationally bound city of stars, gas and dark matter, turning so slowly that a single rotation takes hundreds of millions of years.
  • Lenticular. A lenticular galaxy: it has a disc like a spiral but has run out of the gas needed to make new stars, leaving the arms behind.

Sense of scale

  • In perspective. Further than Andromeda, the most distant thing the unaided human eye can see.
  • Scale. Home to hundreds of billions of stars — a universe unto itself, and every one of those points of light could have planets.

Find it in the sky

  • How to spot it. At magnitude 14.4 it is far too faint for the eye: this one belongs to cameras and long exposures, over in Ursa Major.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around March — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

constellation
UMa
dist ly
42045016.8405
dso type
G
hubble
E-S0
mag
14.42
name
NGC 3931
radial velocity kms
901
redshift
0.003
size arcmin
1.13
surface brightness
23.28

About NGC 3931

NGC 3931 is an uncommon galaxy. It lies about 42,045,016.8 light-years from Earth, sits in the constellation UMa and shines at apparent magnitude 14.42.

A galaxy: a gravitationally bound city of stars, gas and dark matter, turning so slowly that a single rotation takes hundreds of millions of years.

How to see it

Look for NGC 3931 in the constellation UMa. At apparent magnitude 14.42, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, NGC 3931 is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why NGC 3931 is an uncommon galaxy

NGC 3931 scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 5 science badges — Galaxy, Outside our galaxy entirely, Lenticular galaxy (a disc with no arms), Never sets (northern circumpolar) and Faint fuzzy (mag > 13) — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.