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Epic variable star 60 EP

Achird

RA 12.2739° · Dec 57.8152° · star

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Score breakdown

· 10 badges
60 pts · Epic
Epic 78 pts → Anomaly
  • Nearby (<25 ly) +12
  • Naked-eye visible +8
  • Has a proper name +8
  • Sun-like G-type star +8
  • Binary star +6
  • Variable star +5
  • Never sets (northern circumpolar) +4
  • Gently variable +4
  • A named variable star +3
  • Main-sequence star +2
Total score 60

18 more points to reach Anomaly.

Badges

  • Variable star · +5
  • Nearby (<25 ly) · +12
  • Naked-eye visible · +8
  • Binary star · +6
  • Has a proper name · +8
  • Never sets (northern circumpolar) · +4
  • Sun-like G-type star · +8
  • Main-sequence star · +2
  • Gently variable · +4
  • A named variable star · +3

Trivia

What makes it special

  • Not one star but two. It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

What it actually is

  • Spectral class. Its spectrum reads G0V SB — a G-type star: the very same spectral class as our own Sun.
  • Where it is in life. It is on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.
  • 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. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 3.5 you can see it with your own eyes from a dark site, over in Cassiopeia.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around October — that's when to go looking.

Properties

absmag
4.586
binary
yes
bv
0.587
constellation
Cas
dist ly
19.4164
luminosity
1.2753
mag
3.46
name
Achird
named
yes
spect
G0V SB
var amplitude
0.05
var designation
Eta
var max
3.457
var min
3.507

About Achird

Achird is an epic variable star. It lies about 19.4 light-years from Earth, sits in the constellation Cas, shines at apparent magnitude 3.46 and has spectral type G0V SB.

It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

How to see it

Look for Achird in the constellation Cas. At apparent magnitude 3.46, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, Achird 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 Achird is an epic variable star

Achird scores 60 points on Spacedle's rarity scale, which places it in the epic tier. Another 18 points would lift it into a rarer tier.

That score comes from 10 science badges — Variable star, Nearby (<25 ly), Naked-eye visible, Binary star, Has a proper name, Never sets (northern circumpolar), Sun-like G-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.