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Rare star 35 EP

HD 109550

RA 189.0314° · Dec -62.8441° · star

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Score breakdown

· 5 badges
35 pts · Rare
Rare 50 pts → Epic
  • Bright giant +12
  • Under the Southern Cross +8
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Star +3
Total score 35

15 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Under the Southern Cross · +8
  • Hot blue B-type star · +6
  • Bright giant · +12

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9II — 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 bright giant, well on its way to the largest stars there are.

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 8.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Crux.
  • 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 March — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 36.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.234
bv
0.069
constellation
Cru
dist ly
2090.7435
luminosity
108.0438
mag
8.8
name
HD 109550
spect
B9II

About HD 109550

HD 109550 is a rare star. It lies about 2,090.7 light-years from Earth, sits in the constellation Cru, shines at apparent magnitude 8.8 and has spectral type B9II.

Its spectrum reads B9II — 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 109550 in the constellation Cru. At apparent magnitude 8.8, it is an easy target for binoculars.

Like any astronomical target, HD 109550 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 109550 is a rare star

HD 109550 scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Distant (over 1,000 light-years), Under the Southern Cross, Hot blue B-type star and Bright giant — 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.