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Uncommon variable star 29 EP

HD 72878

RA 128.1714° · Dec -55.4699° · star

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Score breakdown

· 6 badges
29 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Variable star +5
  • Subgiant (leaving the main sequence) +5
  • Gently variable +4
  • A named variable star +3
Total score 29

5 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9IV — 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 subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.
  • 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.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 7.5 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Carina.
  • 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.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

absmag
-0.676
bv
0.048
constellation
Car
dist ly
1376.1856
luminosity
162.3305
mag
7.45
name
HD 72878
spect
B9IV
var amplitude
0.15
var designation
V470
var max
7.414
var min
7.564

About HD 72878

HD 72878 is an uncommon variable star. It lies about 1,376.2 light-years from Earth, sits in the constellation Car, shines at apparent magnitude 7.45 and has spectral type B9IV.

Its spectrum reads B9IV — 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 72878 in the constellation Car. At apparent magnitude 7.45, it is an easy target for binoculars.

Like any astronomical target, HD 72878 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 72878 is an uncommon variable star

HD 72878 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, Distant (over 1,000 light-years), Hot blue B-type star, Subgiant (leaving the main sequence), 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.