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Uncommon variable star 30 EP

HD 15450

RA 37.8314° · Dec 56.8978° · star

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Score breakdown

· 6 badges
30 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Giant star +6
  • Variable star +5
  • Gently variable +4
  • A named variable star +3
Total score 30

4 more points to reach Rare.

Badges

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

Trivia

What it actually is

  • Spectral class. Its spectrum reads B1IIIe — 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 a giant. It has already exhausted its core hydrogen and swollen up enormously in response.
  • 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 9 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
1.056
bv
0.34
constellation
Per
dist ly
1259.2896
luminosity
32.9306
mag
8.99
name
HD 15450
spect
B1IIIe
var amplitude
0.19
var designation
V555
var max
8.88
var min
9.07

About HD 15450

HD 15450 is an uncommon variable star. It lies about 1,259.3 light-years from Earth, sits in the constellation Per, shines at apparent magnitude 8.99 and has spectral type B1IIIe.

Its spectrum reads B1IIIe — 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 15450 in the constellation Per. At apparent magnitude 8.99, it is an easy target for binoculars.

Like any astronomical target, HD 15450 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 15450 is an uncommon variable star

HD 15450 scores 30 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 4 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, Giant 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.