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Trash star 11 EP

HD 21438

RA 51.9161° · Dec 8.7652° · 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 A5 — 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 7.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Taurus.
  • 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 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. ≈ 15 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.3 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
0.716
bv
0.321
constellation
Tau
dist ly
851.5822
luminosity
45.0402
mag
7.8
name
HD 21438
spect
A5

About HD 21438

HD 21438 is a trash star. It lies about 851.6 light-years from Earth, sits in the constellation Tau, shines at apparent magnitude 7.8 and has spectral type A5.

Its spectrum reads A5 — 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 21438 in the constellation Tau. At apparent magnitude 7.8, it is an easy target for binoculars.

Like any astronomical target, HD 21438 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 21438 is a trash star

HD 21438 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.