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Trash star 12 EP

HD 139747

RA 234.6244° · Dec 39.2167° · star

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Score breakdown

· 3 badges
12 pts · Trash
Trash 15 pts → Common
  • Distant (over 1,000 light-years) +6
  • Star +3
  • Orange K-type star +3
Total score 12

3 more points to reach Common.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Orange K-type star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads K0 — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.

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 8.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Corona Borealis.
  • 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 May — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 17.9 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.6 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
1.296
bv
0.91
constellation
CrB
dist ly
1019.2375
luminosity
26.3998
mag
8.77
name
HD 139747
spect
K0

About HD 139747

HD 139747 is a trash star. It lies about 1,019.2 light-years from Earth, sits in the constellation CrB, shines at apparent magnitude 8.77 and has spectral type K0.

Its spectrum reads K0 — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.

How to see it

Look for HD 139747 in the constellation CrB. At apparent magnitude 8.77, it is an easy target for binoculars.

Like any astronomical target, HD 139747 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 139747 is a trash star

HD 139747 scores 12 points on Spacedle's rarity scale, which places it in the trash tier. Another 3 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, Distant (over 1,000 light-years) and Orange K-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.