← Back to dex
Rare star 34 EP

HD 46966

RA 99.1079° · Dec 6.0832° · star

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

Computing the sky for your location…

Score breakdown

· 3 badges
34 pts · Rare
Rare 50 pts → Epic
  • Blazing O-type star +26
  • Blue-white star +5
  • Star +3
Total score 34

16 more points to reach Epic.

Badges

  • Star · +3
  • Blazing O-type star · +26
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads O8 — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.

Find it in the sky

  • How to spot it. At magnitude 6.9 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 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 11030 K, against the Sun's 5778 K.

What's in a name

  • Its catalogue. The HD number is from the Henry Draper Catalogue, in which Annie Jump Cannon personally classified the spectra of nearly 400,000 stars — still the largest such feat by one person.

Properties

absmag
-13.13
bv
-0.066
constellation
Mon
luminosity
15559656.3161
mag
6.87
name
HD 46966
spect
O8

About HD 46966

HD 46966 is a rare star. It sits in the constellation Mon, shines at apparent magnitude 6.87 and has spectral type O8.

Its spectrum reads O8 — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.

How to see it

Look for HD 46966 in the constellation Mon. At apparent magnitude 6.87, it is an easy target for binoculars.

Like any astronomical target, HD 46966 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 46966 is a rare star

HD 46966 scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, Blazing O-type 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.