← Back to dex
Trash star 13 EP

HIP 21578

RA 69.4995° · Dec -13.0323° · star

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 3 badges
13 pts · Trash
Trash 15 pts → Common
  • White A-type star +5
  • Subgiant (leaving the main sequence) +5
  • Star +3
Total score 13

2 more points to reach Common.

Badges

  • Star · +3
  • White A-type star · +5
  • Subgiant (leaving the main sequence) · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads A1IV — 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.
  • Where it is in life. It is a subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.

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 Eridanus.
  • 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. ≈ 7.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
2.153
bv
0.2
constellation
Eri
dist ly
445.5682
luminosity
11.9895
mag
7.83
name
HIP 21578
spect
A1IV

About HIP 21578

HIP 21578 is a trash star. It lies about 445.6 light-years from Earth, sits in the constellation Eri, shines at apparent magnitude 7.83 and has spectral type A1IV.

Its spectrum reads A1IV — 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 HIP 21578 in the constellation Eri. At apparent magnitude 7.83, it is an easy target for binoculars.

Like any astronomical target, HIP 21578 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 HIP 21578 is a trash star

HIP 21578 scores 13 points on Spacedle's rarity scale, which places it in the trash tier. Another 2 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, White A-type star and Subgiant (leaving the main sequence) — 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.