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Uncommon star 26 EP

HD 168121

RA 274.8510° · Dec -28.9996° · star

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Score breakdown

· 5 badges
26 pts · Uncommon
Uncommon 34 pts → Rare
  • Toward the galactic centre +8
  • Hot blue B-type star +6
  • Giant star +6
  • Star +3
  • On the zodiac +3
Total score 26

8 more points to reach Rare.

Badges

  • Star · +3
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • Hot blue B-type star · +6
  • Giant star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads B8/B9III — 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.

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 8.3 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Sagittarius.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around June — 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. ≈ 12.4 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.1 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
1.623
bv
0.046
constellation
Sgr
dist ly
702.9223
luminosity
19.5344
mag
8.29
name
HD 168121
spect
B8/B9III

About HD 168121

HD 168121 is an uncommon star. It lies about 702.9 light-years from Earth, sits in the constellation Sgr, shines at apparent magnitude 8.29 and has spectral type B8/B9III.

Its spectrum reads B8/B9III — 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 168121 in the constellation Sgr. At apparent magnitude 8.29, it is an easy target for binoculars.

Like any astronomical target, HD 168121 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 168121 is an uncommon star

HD 168121 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 5 science badges — Star, Toward the galactic centre, On the zodiac, Hot blue B-type star and Giant 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.