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Common variable star 19 EP

HD 31908

RA 71.8944° · Dec -79.8072° · star

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Score breakdown

· 5 badges
19 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • Yellow-white F-type star +3
  • A named variable star +3
  • Barely variable (under 0.05 mag) +2
Total score 19

3 more points to reach Uncommon.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Yellow-white F-type star · +3
  • Barely variable (under 0.05 mag) · +2
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads Fm... — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • 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 7.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Mensa.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • 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. ≈ 25.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.408
bv
0.362
constellation
Men
dist ly
1462.583
luminosity
126.8236
mag
7.85
name
HD 31908
spect
Fm...
var amplitude
0.04
var designation
XZ
var max
7.827
var min
7.867

About HD 31908

HD 31908 is a common variable star. It lies about 1,462.6 light-years from Earth, sits in the constellation Men, shines at apparent magnitude 7.85 and has spectral type Fm....

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

How to see it

Look for HD 31908 in the constellation Men. At apparent magnitude 7.85, it is an easy target for binoculars.

Like any astronomical target, HD 31908 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 31908 is a common variable star

HD 31908 scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 3 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Distant (over 1,000 light-years), Yellow-white F-type star, Barely variable (under 0.05 mag) 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.