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Rare star 37 EP

102 Her

RA 272.1895° · Dec 20.8146° · star

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Score breakdown

· 6 badges
37 pts · Rare
Rare 50 pts → Epic
  • Intrinsically luminous (Mv < −2) +10
  • Naked-eye visible +8
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Blue-white star +5
  • Star +3
Total score 37

13 more points to reach Epic.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5
  • Blue-white star · +5
  • Intrinsically luminous (Mv < −2) · +10

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2IV — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
  • Where it is in life. It is a subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.

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 4.4 you can see it with your own eyes from a dark site, over in Hercules.
  • 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 June — 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. ≈ 16.1 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-2.873
bv
-0.164
constellation
Her
dist ly
916.1686
luminosity
1228.0046
mag
4.37
name
102 Her
spect
B2IV

About 102 Her

102 Her is a rare star. It lies about 916.2 light-years from Earth, sits in the constellation Her, shines at apparent magnitude 4.37 and has spectral type B2IV.

Its spectrum reads B2IV — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for 102 Her in the constellation Her. At apparent magnitude 4.37, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 102 Her 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 102 Her is a rare star

102 Her scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 6 science badges — Star, Naked-eye visible, Hot blue B-type star, Subgiant (leaving the main sequence), Blue-white star and Intrinsically luminous (Mv < −2) — 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.