Uncommon star 31 EP

HD 57236

RA 109.8754° · Dec -22.0048° · star

Loading sky survey…

🌌 View in 3D star map

Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 3 badges

31 pts · Uncommon

Uncommon 34 pts → Rare

Blazing O-type star +26
Star +3
Main-sequence star +2

Total score 31

3 more points to reach Rare.

Badges

Star · +3
Blazing O-type star · +26
Main-sequence star · +2

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 O9V — 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.
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 8.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Canis Major.
Southern sky. It rides the southern half of the sky — an easier target the further south you are.
Best time of year. It stands highest in the middle of the night around January — 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.

Properties

absmag: -11.25
bv: 0.192
constellation: CMa
luminosity: 2754228.7033
mag: 8.75
name: HD 57236
spect: O9V

Nearby objects

About HD 57236

HD 57236 is an uncommon star. It sits in the constellation CMa, shines at apparent magnitude 8.75 and has spectral type O9V.

Its spectrum reads O9V — 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 57236 in the constellation CMa. At apparent magnitude 8.75, it is an easy target for binoculars.

Like any astronomical target, HD 57236 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 57236 is an uncommon star

HD 57236 scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

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