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Trash star 14 EP

HD 41690

RA 91.9121° · Dec 21.8732° · star

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Score breakdown

· 4 badges
14 pts · Trash
Trash 15 pts → Common
  • Hot blue B-type star +6
  • Star +3
  • On the zodiac +3
  • Main-sequence star +2
Total score 14

1 more point to reach Common.

Badges

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

Trivia

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 7.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Gemini.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • 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 0.2) — 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 8150 K, against the Sun's 5778 K.

Properties

absmag
-12.27
bv
0.202
constellation
Gem
luminosity
7046930.6897
mag
7.73
name
HD 41690
spect
B1V

About HD 41690

HD 41690 is a trash star. It sits in the constellation Gem, shines at apparent magnitude 7.73 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 41690 in the constellation Gem. At apparent magnitude 7.73, it is an easy target for binoculars.

Like any astronomical target, HD 41690 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 41690 is a trash star

HD 41690 scores 14 points on Spacedle's rarity scale, which places it in the trash tier. Another 1 point would lift it into a rarer tier.

That score comes from 4 science badges — Star, On the zodiac, 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.