← Back to dex
Uncommon star 33 EP

HD 186320

RA 296.2353° · Dec -33.2546° · star

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

Computing the sky for your location…

Score breakdown

· 6 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Toward the galactic centre +8
  • Deep red star +8
  • Giant star +6
  • Cool red M-type star +5
  • Star +3
  • On the zodiac +3
Total score 33

1 more point to reach Rare.

Badges

  • Star · +3
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • Cool red M-type star · +5
  • Giant star · +6
  • Deep red star · +8

Trivia

Hard to believe

  • True brightness. It pours out about 2.1 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 M2III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • Where it is in life. It is a giant. It has already exhausted its core hydrogen and swollen up enormously in response.

Find it in the sky

  • How to spot it. At magnitude 9 you'll want a small backyard telescope, over in Sagittarius.
  • 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 July — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out deep orange-red (B−V 1.9) — one of the coolest surfaces a star can have while still fusing.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 3310 K, against the Sun's 5778 K.

Properties

absmag
-11
bv
1.874
constellation
Sgr
luminosity
2187761.6239
mag
9
name
HD 186320
spect
M2III

About HD 186320

HD 186320 is an uncommon star. It sits in the constellation Sgr, shines at apparent magnitude 9 and has spectral type M2III.

Its spectrum reads M2III — 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 186320 in the constellation Sgr. At apparent magnitude 9, it is an easy target for binoculars.

Like any astronomical target, HD 186320 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 186320 is an uncommon star

HD 186320 scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 6 science badges — Star, Toward the galactic centre, On the zodiac, Cool red M-type star, Giant star and Deep red 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.