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Common variable star 21 EP

HD 109118

RA 188.0415° · Dec 20.9192° · star

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Score breakdown

· 5 badges
21 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • Gently variable +4
  • Orange K-type star +3
  • A named variable star +3
Total score 21

1 more point to reach Uncommon.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Orange K-type star · +3
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads K2 — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.
  • 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 8.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Coma Berenices.
  • 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 March — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 23.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.469
bv
1.27
constellation
Com
dist ly
1347.7519
luminosity
56.5458
mag
8.55
name
HD 109118
spect
K2
var amplitude
0.14
var designation
IZ
var max
8.5
var min
8.64

Nearby objects

About HD 109118

HD 109118 is a common variable star. It lies about 1,347.8 light-years from Earth, sits in the constellation Com, shines at apparent magnitude 8.55 and has spectral type K2.

Its spectrum reads K2 — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.

How to see it

Look for HD 109118 in the constellation Com. At apparent magnitude 8.55, it is an easy target for binoculars.

Like any astronomical target, HD 109118 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 109118 is a common variable star

HD 109118 scores 21 points on Spacedle's rarity scale, which places it in the common tier. Another 1 point would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Distant (over 1,000 light-years), Orange K-type 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.