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Rare star 39 EP

HR 7890

RA 309.8052° · Dec -2.4130° · star

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Score breakdown

· 7 badges
39 pts · Rare
Rare 50 pts → Epic
  • Intrinsically luminous (Mv < −2) +10
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Giant star +6
  • Blue-white star +5
  • Star +3
  • On the zodiac +3
Total score 39

11 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • On the zodiac · +3
  • 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 B7IIIn — 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 6.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Aquarius.
  • 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. ≈ 31.5 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-2.47
bv
-0.09
constellation
Aqr
dist ly
1792.0658
luminosity
847.2274
mag
6.23
name
HR 7890
spect
B7IIIn

About HR 7890

HR 7890 is a rare star. It lies about 1,792.1 light-years from Earth, sits in the constellation Aqr, shines at apparent magnitude 6.23 and has spectral type B7IIIn.

Its spectrum reads B7IIIn — 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 7890 in the constellation Aqr. At apparent magnitude 6.23, it is an easy target for binoculars.

Like any astronomical target, HR 7890 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 7890 is a rare star

HR 7890 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 7 science badges — Star, Distant (over 1,000 light-years), On the zodiac, 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.