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Trash star 9 EP

HIP 4004

RA 12.8525° · Dec -72.3829° · 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

Hard to believe

  • True brightness. It pours out about 218.8 thousand 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 B5 — 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.

Find it in the sky

  • How to spot it. At magnitude 11.5 you'll want a small backyard telescope, over in Tucana.
  • 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 October — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out brilliant white (B−V 0.1) — hotter and whiter than the Sun, the colour of Sirius or Vega.
  • 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.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 9340 K, against the Sun's 5778 K.

Properties

absmag
-8.52
bv
0.069
constellation
Tuc
luminosity
222843.5149
mag
11.48
name
HIP 4004
spect
B5

About HIP 4004

HIP 4004 is a trash star. It sits in the constellation Tuc, shines at apparent magnitude 11.48 and has spectral type B5.

Its spectrum reads B5 — 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 HIP 4004 in the constellation Tuc. At apparent magnitude 11.48, a small backyard telescope will bring it into view.

Like any astronomical target, HIP 4004 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 HIP 4004 is a trash star

HIP 4004 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.