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Uncommon variable star 29 EP

HD 48424

RA 100.5969° · Dec -22.3607° · star

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Score breakdown

· 6 badges
29 pts · Uncommon
Uncommon 34 pts → Rare
  • Hot blue B-type star +6
  • Giant star +6
  • Variable star +5
  • Blue-white star +5
  • Gently variable +4
  • A named variable star +3
Total score 29

5 more points to reach Rare.

Badges

  • Variable star · +5
  • Hot blue B-type star · +6
  • Giant star · +6
  • Blue-white star · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

Hard to believe

  • True brightness. It pours out about 2.4 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 B9.5III — 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 a giant. It has already exhausted its core hydrogen and swollen up enormously in response.
  • It changes. This star does not hold still: its brightness rises and falls on a rhythm of hours, days or years, either pulsing in size or being eclipsed by a companion.

Find it in the sky

  • How to spot it. At magnitude 8.9 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 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.

Properties

absmag
-11.1
bv
-0.119
constellation
CMa
luminosity
2398832.919
mag
8.9
name
HD 48424
spect
B9.5III
var amplitude
0.08
var designation
NZ
var max
8.861
var min
8.941

About HD 48424

HD 48424 is an uncommon variable star. It sits in the constellation CMa, shines at apparent magnitude 8.9 and has spectral type B9.5III.

Its spectrum reads B9.5III — 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 48424 in the constellation CMa. At apparent magnitude 8.9, it is an easy target for binoculars.

Like any astronomical target, HD 48424 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 48424 is an uncommon variable star

HD 48424 scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Hot blue B-type star, Giant star, Blue-white star, Gently variable and A named variable 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.