← Back to dex
Uncommon star 22 EP

HD 42597

RA 92.9947° · Dec 7.3913° · star

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 5 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • In Orion's hunting ground +6
  • Hot blue B-type star +6
  • Blue-white star +5
  • Star +3
  • Main-sequence star +2
Total score 22

12 more points to reach Rare.

Badges

  • Star · +3
  • In Orion's hunting ground · +6
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5

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 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Orion.
  • 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 blue-white (B−V -0.1) — the hallmark of a surface far hotter than the Sun's.
  • 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 11590 K, against the Sun's 5778 K.

Properties

absmag
-12.96
bv
-0.101
constellation
Ori
luminosity
13304544.1798
mag
7.04
name
HD 42597
spect
B1V

About HD 42597

HD 42597 is an uncommon star. It sits in the constellation Ori, shines at apparent magnitude 7.04 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 42597 in the constellation Ori. At apparent magnitude 7.04, it is an easy target for binoculars.

Like any astronomical target, HD 42597 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 42597 is an uncommon star

HD 42597 scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, In Orion's hunting ground, Hot blue B-type star, Main-sequence star and Blue-white 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.