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Rare star 34 EP

HD 40931

RA 90.6388° · Dec 13.0254° · star

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Score breakdown

· 6 badges
34 pts · Rare
Rare 50 pts → Epic
  • Deep red star +8
  • Distant (over 1,000 light-years) +6
  • In Orion's hunting ground +6
  • Giant star +6
  • Cool red M-type star +5
  • Star +3
Total score 34

16 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • In Orion's hunting ground · +6
  • Cool red M-type star · +5
  • Giant star · +6
  • Deep red star · +8

Trivia

What it actually is

  • Spectral class. Its spectrum reads M0III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • Where it is in life. It is a giant. It has already exhausted its core hydrogen and swollen up enormously in response.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Orion.
  • 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 December — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 30.6 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.681
bv
1.644
constellation
Ori
dist ly
1744.1499
luminosity
409.6378
mag
6.96
name
HD 40931
spect
M0III

About HD 40931

HD 40931 is a rare star. It lies about 1,744.1 light-years from Earth, sits in the constellation Ori, shines at apparent magnitude 6.96 and has spectral type M0III.

Its spectrum reads M0III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.

How to see it

Look for HD 40931 in the constellation Ori. At apparent magnitude 6.96, it is an easy target for binoculars.

Like any astronomical target, HD 40931 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 HD 40931 is a rare star

HD 40931 scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 6 science badges — Star, Distant (over 1,000 light-years), In Orion's hunting ground, Cool red M-type star, Giant star and Deep red star — 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.