← Back to dex
Uncommon variable star 31 EP

HD 158890

RA 263.5487° · Dec -48.4686° · star

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

Computing the sky for your location…

Score breakdown

· 6 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Deep red star +8
  • Giant star +6
  • Variable star +5
  • Cool red M-type star +5
  • Gently variable +4
  • A named variable star +3
Total score 31

3 more points to reach Rare.

Badges

  • Variable star · +5
  • Cool red M-type star · +5
  • Giant star · +6
  • Deep red star · +8
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M3/M4III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • 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 7.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Ara.
  • 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 June — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 12.2 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.95
bv
1.634
constellation
Ara
dist ly
693.9491
luminosity
36.3078
mag
7.59
name
HD 158890
spect
M3/M4III
var amplitude
0.14
var designation
V865
var max
7.528
var min
7.668

About HD 158890

HD 158890 is an uncommon variable star. It lies about 693.9 light-years from Earth, sits in the constellation Ara, shines at apparent magnitude 7.59 and has spectral type M3/M4III.

Its spectrum reads M3/M4III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.

How to see it

Look for HD 158890 in the constellation Ara. At apparent magnitude 7.59, it is an easy target for binoculars.

Like any astronomical target, HD 158890 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 158890 is an uncommon variable star

HD 158890 scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Cool red M-type star, Giant star, Deep red 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.