← Back to dex
Uncommon variable star 26 EP

HD 90912

RA 157.0702° · Dec -59.3502° · star

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

Computing the sky for your location…

Score breakdown

· 4 badges
26 pts · Uncommon
Uncommon 34 pts → Rare
  • Strongly variable +10
  • Sun-like G-type star +8
  • Variable star +5
  • A named variable star +3
Total score 26

8 more points to reach Rare.

Badges

  • Variable star · +5
  • Sun-like G-type star · +8
  • Strongly variable · +10
  • A named variable star · +3

Trivia

Hard to believe

  • True brightness. It pours out about 3 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 G5 — a G-type star: the very same spectral class as our own Sun.
  • 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 8.6 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 February — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out orange (B−V 1) — cooler than the Sun, and the kind of star that burns steadily for tens of billions of years.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 4660 K, against the Sun's 5778 K.

Properties

absmag
-11.36
bv
1.035
constellation
Car
luminosity
3047894.9896
mag
8.64
name
HD 90912
spect
G5
var amplitude
0.72
var designation
YZ
var max
8.302
var min
9.022

About HD 90912

HD 90912 is an uncommon variable star. It sits in the constellation Car, shines at apparent magnitude 8.64 and has spectral type G5.

Its spectrum reads G5 — a G-type star: the very same spectral class as our own Sun.

How to see it

Look for HD 90912 in the constellation Car. At apparent magnitude 8.64, it is an easy target for binoculars.

Like any astronomical target, HD 90912 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 90912 is an uncommon variable star

HD 90912 scores 26 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 8 points would lift it into a rarer tier.

That score comes from 4 science badges — Variable star, Sun-like G-type star, Strongly 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.