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Trash star 6 EP

HD 21817

RA 52.4666° · Dec -32.6383° · star

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Score breakdown

· 2 badges
6 pts · Trash
Trash 15 pts → Common
  • Star +3
  • Yellow-white F-type star +3
Total score 6

9 more points to reach Common.

Badges

  • Star · +3
  • Yellow-white F-type star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads Fm — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

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 8.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Fornax.
  • 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 November — 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. ≈ 13.1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.2 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
1.937
bv
0.406
constellation
For
dist ly
744.6484
luminosity
14.6285
mag
8.73
name
HD 21817
spect
Fm

About HD 21817

HD 21817 is a trash star. It lies about 744.6 light-years from Earth, sits in the constellation For, shines at apparent magnitude 8.73 and has spectral type Fm.

Its spectrum reads Fm — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 21817 in the constellation For. At apparent magnitude 8.73, it is an easy target for binoculars.

Like any astronomical target, HD 21817 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 21817 is a trash star

HD 21817 scores 6 points on Spacedle's rarity scale, which places it in the trash tier. Another 9 points would lift it into a rarer tier.

That score comes from 2 science badges — Star and Yellow-white F-type 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.