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Rare star 39 EP

HD 15629

RA 38.3358° · Dec 61.5217° · 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 O5e — 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 8.5 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cassiopeia.
  • 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 October — 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. ≈ 23.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 2.1 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
0.415
bv
0.362
constellation
Cas
dist ly
1325.8375
luminosity
59.4292
mag
8.46
name
HD 15629
spect
O5e

About HD 15629

HD 15629 is a rare star. It lies about 1,325.8 light-years from Earth, sits in the constellation Cas, shines at apparent magnitude 8.46 and has spectral type O5e.

Its spectrum reads O5e — 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 HD 15629 in the constellation Cas. At apparent magnitude 8.46, it is an easy target for binoculars.

Like any astronomical target, HD 15629 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 15629 is a rare star

HD 15629 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.