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Trash star 11 EP

HD 171305

RA 278.5660° · Dec -4.8136° · star

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Score breakdown

· 3 badges
11 pts · Trash
Trash 15 pts → Common
  • Hot blue B-type star +6
  • Star +3
  • Main-sequence star +2
Total score 11

4 more points to reach Common.

Badges

  • Star · +3
  • Hot blue B-type star · +6
  • Main-sequence star · +2

Trivia

Hard to believe

  • True brightness. It pours out about 2.8 million times as much light as the Sun. It only looks ordinary because it is so far away.

What it actually is

  • Spectral class. Its spectrum reads B1V — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

Find it in the sky

  • How to spot it. At magnitude 8.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Scutum.
  • 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 June — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out yellow-white (B−V 0.4) — a shade brighter and crisper than our own Sun.
  • Why no green stars. No star ever looks green: a surface hot enough to peak in green also floods out plenty of red and blue, and your eye blends the mixture back to white.

Properties

absmag
-11.29
bv
0.449
constellation
Sct
luminosity
2857590.5434
mag
8.71
name
HD 171305
spect
B1V

Nearby objects

About HD 171305

HD 171305 is a trash star. It sits in the constellation Sct, shines at apparent magnitude 8.71 and has spectral type B1V.

Its spectrum reads B1V — 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 171305 in the constellation Sct. At apparent magnitude 8.71, it is an easy target for binoculars.

Like any astronomical target, HD 171305 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 171305 is a trash star

HD 171305 scores 11 points on Spacedle's rarity scale, which places it in the trash tier. Another 4 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, Hot blue B-type star and Main-sequence 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.