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Common star 16 EP

HD 104839

RA 181.0696° · Dec -51.4725° · star

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Score breakdown

· 4 badges
16 pts · Common
Common 22 pts → Uncommon
  • Hot blue B-type star +6
  • Blue-white star +5
  • Star +3
  • Main-sequence star +2
Total score 16

6 more points to reach Uncommon.

Badges

  • Star · +3
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9V — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

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 6.5 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Centaurus.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • 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. ≈ 6.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.127
bv
-0.046
constellation
Cen
dist ly
383.7131
luminosity
30.8461
mag
6.48
name
HD 104839
spect
B9V

About HD 104839

HD 104839 is a common star. It lies about 383.7 light-years from Earth, sits in the constellation Cen, shines at apparent magnitude 6.48 and has spectral type B9V.

Its spectrum reads B9V — 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 HD 104839 in the constellation Cen. At apparent magnitude 6.48, it is an easy target for binoculars.

Like any astronomical target, HD 104839 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 104839 is a common star

HD 104839 scores 16 points on Spacedle's rarity scale, which places it in the common tier. Another 6 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Hot blue B-type star, Main-sequence star and Blue-white 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.