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Rare star 39 EP

HIP 172

RA 0.5429° · Dec 67.4090° · star

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Score breakdown

· 4 badges
39 pts · Rare
Rare 50 pts → Epic
  • Blazing O-type star +26
  • Distant (over 1,000 light-years) +6
  • Never sets (northern circumpolar) +4
  • Star +3
Total score 39

11 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Never sets (northern circumpolar) · +4
  • Blazing O-type star · +26

Trivia

What it actually is

  • Spectral class. Its spectrum reads O7 — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.

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 9.1 you'll want a small backyard telescope, over in Cepheus.
  • 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 September — 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. ≈ 50.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 4.5 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-0.665
bv
0.976
constellation
Cep
dist ly
2861.0176
luminosity
160.6941
mag
9.05
name
HIP 172
spect
O7

About HIP 172

HIP 172 is a rare star. It lies about 2,861 light-years from Earth, sits in the constellation Cep, shines at apparent magnitude 9.05 and has spectral type O7.

Its spectrum reads O7 — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.

How to see it

Look for HIP 172 in the constellation Cep. At apparent magnitude 9.05, a small backyard telescope will bring it into view.

Like any astronomical target, HIP 172 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 172 is a rare star

HIP 172 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Distant (over 1,000 light-years), Never sets (northern circumpolar) and Blazing O-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.