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Trash star 11 EP

HR 1721

RA 78.6202° · Dec -35.9770° · star

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Score breakdown

· 2 badges
11 pts · Trash
Trash 15 pts → Common
  • Naked-eye visible +8
  • Star +3
Total score 11

4 more points to reach Common.

Badges

  • Star · +3
  • Naked-eye visible · +8

Trivia

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 8.7 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 776.3 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 4972 years in a starship at a tenth of light speed.
  • Distance. 497 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1529.

Saying hello

  • Say hello. A radio message and its reply would take 994 years round-trip.

Properties

absmag
-0.165
bv
1.009
constellation
Col
dist ly
497.1889
mag
5.75
name
HR 1721
spect
G8III

About HR 1721

HR 1721 is a trash star. It lies about 497.2 light-years from Earth, sits in the constellation Col, shines at apparent magnitude 5.75 and has spectral type G8III.

HR 1721 is a trash star worth 11 points across 2 science badges. Explore its facts, badges and place on the sky map, then add it to your dex on Spacedle.

How to see it

Look for HR 1721 in the constellation Col. At apparent magnitude 5.75, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 1721 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 HR 1721 is a trash star

HR 1721 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 2 science badges — Star and Naked-eye visible — 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.