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Uncommon star 22 EP

HD 118840

RA 204.8079° · Dec 10.5097° · star

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Score breakdown

· 4 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Deep red star +8
  • Giant star +6
  • Cool red M-type star +5
  • Star +3
Total score 22

12 more points to reach Rare.

Badges

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

Trivia

What it actually is

  • Spectral class. Its spectrum reads M3III — 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 6.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Boötes.
  • 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 April — 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. ≈ 15.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.549
bv
1.463
constellation
Boo
dist ly
893.5781
luminosity
144.4109
mag
6.64
name
HD 118840
spect
M3III

About HD 118840

HD 118840 is an uncommon star. It lies about 893.6 light-years from Earth, sits in the constellation Boo, shines at apparent magnitude 6.64 and has spectral type M3III.

Its spectrum reads M3III — 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 118840 in the constellation Boo. At apparent magnitude 6.64, it is an easy target for binoculars.

Like any astronomical target, HD 118840 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 118840 is an uncommon star

HD 118840 scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, 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.