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Rare variable star 37 EP

GL Gl 669A

RA 259.9759° · Dec 26.5008° · star

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Score breakdown

· 7 badges
37 pts · Rare
Rare 50 pts → Epic
  • Deep red star +8
  • Binary star +6
  • Red dwarf +6
  • Variable star +5
  • Cool red M-type star +5
  • Gently variable +4
  • A named variable star +3
Total score 37

13 more points to reach Epic.

Badges

  • Variable star · +5
  • Binary star · +6
  • Cool red M-type star · +5
  • Deep red star · +8
  • Red dwarf · +6
  • Gently variable · +4
  • A named variable star · +3

Trivia

What makes it special

  • Not one star but two. It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

What it actually is

  • Spectral class. Its spectrum reads M4 — 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. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 11.3 you'll want a small backyard telescope, over in Hercules.
  • 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 June — that's when to go looking.

Could we get there?

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

Properties

absmag
10.939
binary
yes
bv
1.628
constellation
Her
dist ly
37.8064
luminosity
0.0037
mag
11.26
name
GL Gl 669A
spect
M4
var amplitude
0.25
var designation
V647
var max
11.147
var min
11.397

About GL Gl 669A

GL Gl 669A is a rare variable star. It lies about 37.8 light-years from Earth, sits in the constellation Her, shines at apparent magnitude 11.26 and has spectral type M4.

It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

How to see it

Look for GL Gl 669A in the constellation Her. At apparent magnitude 11.26, a small backyard telescope will bring it into view.

Like any astronomical target, GL Gl 669A 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 GL Gl 669A is a rare variable star

GL Gl 669A scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Binary star, Cool red M-type star, Deep red star, Red dwarf, 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.