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Trash star 9 EP

HD 172850

RA 280.6246° · Dec -1.3059° · star

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Score breakdown

· 2 badges
9 pts · Trash
Trash 15 pts → Common
  • Hot blue B-type star +6
  • Star +3
Total score 9

6 more points to reach Common.

Badges

  • Star · +3
  • Hot blue B-type star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9 — 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 7.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Aquila.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around July — 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. ≈ 11.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
1.239
bv
0.033
constellation
Aql
dist ly
660.2347
luminosity
27.8227
mag
7.77
name
HD 172850
spect
B9

About HD 172850

HD 172850 is a trash star. It lies about 660.2 light-years from Earth, sits in the constellation Aql, shines at apparent magnitude 7.77 and has spectral type B9.

Its spectrum reads B9 — 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 172850 in the constellation Aql. At apparent magnitude 7.77, it is an easy target for binoculars.

Like any astronomical target, HD 172850 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 172850 is a trash star

HD 172850 scores 9 points on Spacedle's rarity scale, which places it in the trash tier. Another 6 points would lift it into a rarer tier.

That score comes from 2 science badges — Star and Hot blue B-type 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.