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Rare variable star 35 EP

HD 166329

RA 275.0681° · Dec -77.6719° · star

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Score breakdown

· 6 badges
35 pts · Rare
Rare 50 pts → Epic
  • Strongly variable +10
  • Distant (over 1,000 light-years) +6
  • Red dwarf +6
  • Variable star +5
  • Cool red M-type star +5
  • A named variable star +3
Total score 35

15 more points to reach Epic.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Cool red M-type star · +5
  • Red dwarf · +6
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M5 — 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 8.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Octans.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • 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. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 28.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.434
bv
1.352
constellation
Oct
dist ly
1638.975
luminosity
58.3983
mag
8.94
name
HD 166329
spect
M5
var amplitude
0.54
var designation
BR
var max
8.666
var min
9.206

About HD 166329

HD 166329 is a rare variable star. It lies about 1,639 light-years from Earth, sits in the constellation Oct, shines at apparent magnitude 8.94 and has spectral type M5.

Its spectrum reads M5 — 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 166329 in the constellation Oct. At apparent magnitude 8.94, it is an easy target for binoculars.

Like any astronomical target, HD 166329 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 166329 is a rare variable star

HD 166329 scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Distant (over 1,000 light-years), Cool red M-type star, Red dwarf, 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.