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Uncommon star 25 EP

HR 8121

RA 318.6544° · Dec 0.0923° · star

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Score breakdown

· 5 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Deep red star +8
  • Giant star +6
  • Cool red M-type star +5
  • Star +3
  • On the zodiac +3
Total score 25

9 more points to reach Rare.

Badges

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

Trivia

What it actually is

  • Spectral class. Its spectrum reads M1III — 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.

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 6.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Aquarius.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around August — 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. ≈ 16.6 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.931
bv
1.574
constellation
Aqr
dist ly
945.3798
luminosity
205.3052
mag
6.38
name
HR 8121
spect
M1III

About HR 8121

HR 8121 is an uncommon star. It lies about 945.4 light-years from Earth, sits in the constellation Aqr, shines at apparent magnitude 6.38 and has spectral type M1III.

Its spectrum reads M1III — 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 HR 8121 in the constellation Aqr. At apparent magnitude 6.38, it is an easy target for binoculars.

Like any astronomical target, HR 8121 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 HR 8121 is an uncommon star

HR 8121 scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, 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.