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Common star 15 EP

HD 100104

RA 172.9875° · Dec 72.5506° · star

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Score breakdown

· 3 badges
15 pts · Common
Common 22 pts → Uncommon
  • Sun-like G-type star +8
  • Never sets (northern circumpolar) +4
  • Star +3
Total score 15

7 more points to reach Uncommon.

Badges

  • Star · +3
  • Never sets (northern circumpolar) · +4
  • Sun-like G-type star · +8

Trivia

What it actually is

  • Spectral class. Its spectrum reads G5 — a G-type star: the very same spectral class as our own Sun.

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 9.3 you'll want a small backyard telescope, over in Draco.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around March — 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. ≈ 10.9 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 966.3 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
2.959
bv
0.712
constellation
Dra
dist ly
618.8918
luminosity
5.7069
mag
9.35
name
HD 100104
spect
G5

About HD 100104

HD 100104 is a common star. It lies about 618.9 light-years from Earth, sits in the constellation Dra, shines at apparent magnitude 9.35 and has spectral type G5.

Its spectrum reads G5 — a G-type star: the very same spectral class as our own Sun.

How to see it

Look for HD 100104 in the constellation Dra. At apparent magnitude 9.35, a small backyard telescope will bring it into view.

Like any astronomical target, HD 100104 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 100104 is a common star

HD 100104 scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, Never sets (northern circumpolar) and Sun-like G-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.