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Common star 17 EP

HR 6900

RA 276.2870° · Dec 5.0846° · star

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Score breakdown

· 4 badges
17 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Star +3
  • Main-sequence star +2
Total score 17

5 more points to reach Uncommon.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Main-sequence star · +2

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 6.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Serpens.
  • 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 June — 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. ≈ 18.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.849
bv
0.011
constellation
Ser
dist ly
1069.3641
luminosity
190.3707
mag
6.73
name
HR 6900
spect
B9V

About HR 6900

HR 6900 is a common star. It lies about 1,069.4 light-years from Earth, sits in the constellation Ser, shines at apparent magnitude 6.73 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 HR 6900 in the constellation Ser. At apparent magnitude 6.73, it is an easy target for binoculars.

Like any astronomical target, HR 6900 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 HR 6900 is a common star

HR 6900 scores 17 points on Spacedle's rarity scale, which places it in the common tier. Another 5 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Distant (over 1,000 light-years), Hot blue B-type star and Main-sequence 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.