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Common variable star 21 EP

HD 80731

RA 141.0136° · Dec 61.7730° · star

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Score breakdown

· 6 badges
21 pts · Common
Common 22 pts → Uncommon
  • Variable star +5
  • Never sets (northern circumpolar) +4
  • Gently variable +4
  • Yellow-white F-type star +3
  • A named variable star +3
  • Main-sequence star +2
Total score 21

1 more point to reach Uncommon.

Badges

  • Variable star · +5
  • Never sets (northern circumpolar) · +4
  • Yellow-white F-type star · +3
  • Main-sequence star · +2
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads F0V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • Where it is in life. It is on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.
  • It changes. This star does not hold still: its brightness rises and falls on a rhythm of hours, days or years, either pulsing in size or being eclipsed by a companion.

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 8.5 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Ursa Major.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around February — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Properties

absmag
2.501
bv
0.345
constellation
UMa
dist ly
507.2411
luminosity
8.7016
mag
8.46
name
HD 80731
spect
F0V
var amplitude
0.12
var designation
LU
var max
8.389
var min
8.509

About HD 80731

HD 80731 is a common variable star. It lies about 507.2 light-years from Earth, sits in the constellation UMa, shines at apparent magnitude 8.46 and has spectral type F0V.

Its spectrum reads F0V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 80731 in the constellation UMa. At apparent magnitude 8.46, it is an easy target for binoculars.

Like any astronomical target, HD 80731 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 80731 is a common variable star

HD 80731 scores 21 points on Spacedle's rarity scale, which places it in the common tier. Another 1 point would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Never sets (northern circumpolar), Yellow-white F-type star, Main-sequence star, Gently variable and A named variable 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.