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Uncommon variable star 26 EP

HD 187851

RA 297.7697° · Dec 27.7169° · star

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Score breakdown

· 6 badges
26 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Variable star +5
  • Gently variable +4
  • A named variable star +3
  • Main-sequence star +2
Total score 26

8 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2V:nn — 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 7.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Vulpecula.
  • 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
-0.107
bv
0.079
constellation
Vul
dist ly
1221.5579
luminosity
96.117
mag
7.76
name
HD 187851
spect
B2V:nn
var amplitude
0.08
var designation
V396
var max
7.724
var min
7.804

About HD 187851

HD 187851 is an uncommon variable star. It lies about 1,221.6 light-years from Earth, sits in the constellation Vul, shines at apparent magnitude 7.76 and has spectral type B2V:nn.

Its spectrum reads B2V:nn — 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 HD 187851 in the constellation Vul. At apparent magnitude 7.76, it is an easy target for binoculars.

Like any astronomical target, HD 187851 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 187851 is an uncommon variable star

HD 187851 scores 26 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 8 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Distant (over 1,000 light-years), Hot blue B-type star, Main-sequence star, 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.