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Trash star 3 EP

HD 221728

RA 353.5897° · Dec 50.2093° · star

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Score breakdown

· 1 badge
3 pts · Trash
Trash 15 pts → Common
  • Star +3
Total score 3

12 more points to reach Common.

Badges

  • Star · +3

Trivia

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.
  • At 10% light speed. ≈ 8516 years in a starship at a tenth of light speed.
  • Distance. 852 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1174.

Saying hello

  • Say hello. A radio message and its reply would take 1703 years round-trip.

Properties

absmag
2.296
bv
-0.056
constellation
And
dist ly
851.5822
mag
9.38
name
HD 221728
spect
B9

About HD 221728

HD 221728 is a trash star. It lies about 851.6 light-years from Earth, sits in the constellation And, shines at apparent magnitude 9.38 and has spectral type B9.

HD 221728 is a trash star worth 3 points across 1 science badge. Explore its facts, badges and place on the sky map, then add it to your dex on Spacedle.

How to see it

Look for HD 221728 in the constellation And. At apparent magnitude 9.38, a small backyard telescope will bring it into view.

Like any astronomical target, HD 221728 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 221728 is a trash star

HD 221728 scores 3 points on Spacedle's rarity scale, which places it in the trash tier. Another 12 points would lift it into a rarer tier.

That score comes from 1 science badge — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.