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Trash star 14 EP

HD 121810

RA 210.0722° · Dec -67.5057° · star

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Score breakdown

· 3 badges
14 pts · Trash
Trash 15 pts → Common
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Star +3
Total score 14

1 more point to reach Common.

Badges

  • Star · +3
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9IV — 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.

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 7.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Circinus.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • Best time of year. It stands highest in the middle of the night around April — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 14.9 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.482
bv
0.032
constellation
Cir
dist ly
849.3647
luminosity
55.8727
mag
7.56
name
HD 121810
spect
B9IV

About HD 121810

HD 121810 is a trash star. It lies about 849.4 light-years from Earth, sits in the constellation Cir, shines at apparent magnitude 7.56 and has spectral type B9IV.

Its spectrum reads B9IV — 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 121810 in the constellation Cir. At apparent magnitude 7.56, it is an easy target for binoculars.

Like any astronomical target, HD 121810 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 121810 is a trash star

HD 121810 scores 14 points on Spacedle's rarity scale, which places it in the trash tier. Another 1 point would lift it into a rarer tier.

That score comes from 3 science badges — Star, Hot blue B-type star and Subgiant (leaving the main sequence) — 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.