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Uncommon variable star 33 EP

HD 1810

RA 5.7222° · Dec 62.2414° · star

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Score breakdown

· 7 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Variable star +5
  • Subgiant (leaving the main sequence) +5
  • Never sets (northern circumpolar) +4
  • Gently variable +4
  • A named variable star +3
Total score 33

1 more point to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Never sets (northern circumpolar) · +4
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B0IV — 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 subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.
  • 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 8.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cassiopeia.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around September — that's when to go looking.

Could we get there?

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

Properties

absmag
0.294
bv
0.06
constellation
Cas
dist ly
1226.1502
luminosity
66.4355
mag
8.17
name
HD 1810
spect
B0IV
var amplitude
0.13
var designation
V745
var max
8.109
var min
8.239

About HD 1810

HD 1810 is an uncommon variable star. It lies about 1,226.2 light-years from Earth, sits in the constellation Cas, shines at apparent magnitude 8.17 and has spectral type B0IV.

Its spectrum reads B0IV — 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 1810 in the constellation Cas. At apparent magnitude 8.17, it is an easy target for binoculars.

Like any astronomical target, HD 1810 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 1810 is an uncommon variable star

HD 1810 scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Distant (over 1,000 light-years), Never sets (northern circumpolar), Hot blue B-type star, Subgiant (leaving the main sequence), 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.