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Epic variable star 59 EP

HR 1939

RA 85.1752° · Dec 31.9206° · star

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Score breakdown

· 8 badges
59 pts · Epic
Epic 78 pts → Anomaly
  • Supergiant +18
  • Intrinsically luminous (Mv < −2) +10
  • Deep red star +8
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • Cool red M-type star +5
  • Gently variable +4
  • A named variable star +3
Total score 59

19 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
  • Intrinsically luminous (Mv < −2) · +10
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M2SIab — 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. Drop it where the Sun is and its surface would engulf the inner planets.
  • 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 6.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Auriga.
  • 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.

Properties

absmag
-2.643
bv
2.088
constellation
Aur
dist ly
1941.4048
luminosity
993.5735
mag
6.23
name
HR 1939
spect
M2SIab
var amplitude
0.17
var designation
NO
var max
6.117
var min
6.287

About HR 1939

HR 1939 is an epic variable star. It lies about 1,941.4 light-years from Earth, sits in the constellation Aur, shines at apparent magnitude 6.23 and has spectral type M2SIab.

Its spectrum reads M2SIab — 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 HR 1939 in the constellation Aur. At apparent magnitude 6.23, it is an easy target for binoculars.

Like any astronomical target, HR 1939 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 HR 1939 is an epic variable star

HR 1939 scores 59 points on Spacedle's rarity scale, which places it in the epic tier. Another 19 points would lift it into a rarer tier.

That score comes from 8 science badges — Variable star, Distant (over 1,000 light-years), Cool red M-type star, Supergiant, Deep red star, Intrinsically luminous (Mv < −2), 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.