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Rare variable star 49 EP

28 Cyg

RA 302.3567° · Dec 36.8396° · star

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Score breakdown

· 9 badges
49 pts · Rare
Rare 50 pts → Epic
  • Intrinsically luminous (Mv < −2) +10
  • Naked-eye visible +8
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Variable star +5
  • Blue-white star +5
  • Gently variable +4
  • A named variable star +3
  • Main-sequence star +2
Total score 49

1 more point to reach Epic.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5
  • Intrinsically luminous (Mv < −2) · +10
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2.5V — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
  • Where it is in life. It is on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.
  • 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 4.9 you can see it with your own eyes from a dark site, over in Cygnus.
  • 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 July — that's when to go looking.

Could we get there?

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

Properties

absmag
-2.578
bv
-0.139
constellation
Cyg
dist ly
1035.4158
luminosity
935.8365
mag
4.93
name
28 Cyg
spect
B2.5V
var amplitude
0.1
var designation
V1624
var max
4.866
var min
4.966

About 28 Cyg

28 Cyg is a rare variable star. It lies about 1,035.4 light-years from Earth, sits in the constellation Cyg, shines at apparent magnitude 4.93 and has spectral type B2.5V.

Its spectrum reads B2.5V — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for 28 Cyg in the constellation Cyg. At apparent magnitude 4.93, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 28 Cyg 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 28 Cyg is a rare variable star

28 Cyg scores 49 points on Spacedle's rarity scale, which places it in the rare tier. Another 1 point would lift it into a rarer tier.

That score comes from 9 science badges — Variable star, Distant (over 1,000 light-years), Naked-eye visible, Hot blue B-type star, Main-sequence star, Blue-white star, Intrinsically luminous (Mv < −2) and Gently variable — 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.