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Rare variable star 34 EP

HD 25725

RA 61.0783° · Dec -15.7251° · star

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Score breakdown

· 6 badges
34 pts · Rare
Rare 50 pts → Epic
  • Strongly variable +10
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • Cool red M-type star +5
  • Subgiant (leaving the main sequence) +5
  • A named variable star +3
Total score 34

16 more points to reach Epic.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Cool red M-type star · +5
  • Subgiant (leaving the main sequence) · +5
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M5/M6IV — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • 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 8.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Eridanus.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around November — 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. ≈ 25.1 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.35
bv
1.317
constellation
Eri
dist ly
1430.5088
luminosity
63.0957
mag
8.56
name
HD 25725
spect
M5/M6IV
var amplitude
0.57
var designation
V
var max
8.29
var min
8.86

About HD 25725

HD 25725 is a rare variable star. It lies about 1,430.5 light-years from Earth, sits in the constellation Eri, shines at apparent magnitude 8.56 and has spectral type M5/M6IV.

Its spectrum reads M5/M6IV — 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 25725 in the constellation Eri. At apparent magnitude 8.56, it is an easy target for binoculars.

Like any astronomical target, HD 25725 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 25725 is a rare variable star

HD 25725 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 — Variable star, Distant (over 1,000 light-years), Cool red M-type star, Subgiant (leaving the main sequence), Strongly 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.