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Trash star 8 EP

HD 45258

RA 96.5816° · Dec -3.5849° · star

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Score breakdown

· 2 badges
8 pts · Trash
Trash 15 pts → Common
  • White A-type star +5
  • Star +3
Total score 8

7 more points to reach Common.

Badges

  • Star · +3
  • White A-type star · +5

Trivia

Hard to believe

  • True brightness. It pours out about 2.7 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 A2 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

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 Monoceros.
  • 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 December — 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 0.3) — 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 7560 K, against the Sun's 5778 K.

Properties

absmag
-11.24
bv
0.285
constellation
Mon
luminosity
2728977.7828
mag
8.76
name
HD 45258
spect
A2

About HD 45258

HD 45258 is a trash star. It sits in the constellation Mon, shines at apparent magnitude 8.76 and has spectral type A2.

Its spectrum reads A2 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

How to see it

Look for HD 45258 in the constellation Mon. At apparent magnitude 8.76, it is an easy target for binoculars.

Like any astronomical target, HD 45258 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 45258 is a trash star

HD 45258 scores 8 points on Spacedle's rarity scale, which places it in the trash tier. Another 7 points would lift it into a rarer tier.

That score comes from 2 science badges — Star and White A-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.