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Trash star 11 EP

HD 20921

RA 50.8749° · Dec 30.4391° · star

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Score breakdown

· 3 badges
11 pts · Trash
Trash 15 pts → Common
  • White A-type star +5
  • Star +3
  • On the zodiac +3
Total score 11

4 more points to reach Common.

Badges

  • Star · +3
  • On the zodiac · +3
  • White A-type star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads A0 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

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 8.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Aries.
  • 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 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. ≈ 13.4 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
1.527
bv
0.272
constellation
Ari
dist ly
762.0469
luminosity
21.3403
mag
8.37
name
HD 20921
spect
A0

About HD 20921

HD 20921 is a trash star. It lies about 762 light-years from Earth, sits in the constellation Ari, shines at apparent magnitude 8.37 and has spectral type A0.

Its spectrum reads A0 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

How to see it

Look for HD 20921 in the constellation Ari. At apparent magnitude 8.37, it is an easy target for binoculars.

Like any astronomical target, HD 20921 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 20921 is a trash star

HD 20921 scores 11 points on Spacedle's rarity scale, which places it in the trash tier. Another 4 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, On the zodiac and White A-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.