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Epic variable star 55 EP

HD 12401

RA 30.7890° · Dec 55.2324° · star

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Score breakdown

· 7 badges
55 pts · Epic
Epic 78 pts → Anomaly
  • Supergiant +18
  • Strongly variable +10
  • Deep red star +8
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • Cool red M-type star +5
  • A named variable star +3
Total score 55

23 more points to reach Anomaly.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Cool red M-type star · +5
  • Supergiant · +18
  • Deep red star · +8
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M4Ib+... — 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 supergiant, hundreds of times wider 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 8.1 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Perseus.
  • 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 October — that's when to go looking.

Could we get there?

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

Properties

absmag
-1.605
bv
1.5
constellation
Per
dist ly
2861.0176
luminosity
381.9443
mag
8.11
name
HD 12401
spect
M4Ib+...
var amplitude
0.64
var designation
XX
var max
7.916
var min
8.556

About HD 12401

HD 12401 is an epic variable star. It lies about 2,861 light-years from Earth, sits in the constellation Per, shines at apparent magnitude 8.11 and has spectral type M4Ib+....

Its spectrum reads M4Ib+... — 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 12401 in the constellation Per. At apparent magnitude 8.11, it is an easy target for binoculars.

Like any astronomical target, HD 12401 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 12401 is an epic variable star

HD 12401 scores 55 points on Spacedle's rarity scale, which places it in the epic tier. Another 23 points would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Distant (over 1,000 light-years), Cool red M-type star, Supergiant, Deep red star, 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.