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Rare star 44 EP

39Kap Aql

RA 294.2227° · Dec -7.0275° · star

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Score breakdown

· 7 badges
44 pts · Rare
Rare 50 pts → Epic
  • Intrinsically luminous (Mv < −2) +10
  • Naked-eye visible +8
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Giant star +6
  • Blue-white star +5
  • Star +3
Total score 44

6 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Giant star · +6
  • Blue-white star · +5
  • Intrinsically luminous (Mv < −2) · +10

Trivia

What it actually is

  • Spectral class. Its spectrum reads B0.5III — 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 giant. It has already exhausted its core hydrogen and swollen up enormously in response.

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 4.9 you can see it with your own eyes from a dark site, over in Aquila.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around July — 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. ≈ 29.5 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-3.631
bv
-0.046
constellation
Aql
dist ly
1681.2164
luminosity
2468.3117
mag
4.93
name
39Kap Aql
spect
B0.5III

About 39Kap Aql

39Kap Aql is a rare star. It lies about 1,681.2 light-years from Earth, sits in the constellation Aql, shines at apparent magnitude 4.93 and has spectral type B0.5III.

Its spectrum reads B0.5III — 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 39Kap Aql in the constellation Aql. At apparent magnitude 4.93, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 39Kap Aql 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 39Kap Aql is a rare star

39Kap Aql scores 44 points on Spacedle's rarity scale, which places it in the rare tier. Another 6 points would lift it into a rarer tier.

That score comes from 7 science badges — Star, Distant (over 1,000 light-years), Naked-eye visible, Hot blue B-type star, Giant star, 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.