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Rare star 43 EP

HD 177423

RA 286.3120° · Dec -16.8668° · star

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Score breakdown

· 7 badges
43 pts · Rare
Rare 50 pts → Epic
  • Bright giant +12
  • Toward the galactic centre +8
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Blue-white star +5
  • Star +3
  • On the zodiac +3
Total score 43

7 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • Hot blue B-type star · +6
  • Bright giant · +12
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B5II — 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 bright giant, well on its way to the largest stars there are.

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 8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Sagittarius.
  • 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 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. ≈ 27.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.451
bv
-0.027
constellation
Sgr
dist ly
1583.2816
luminosity
131.9471
mag
7.98
name
HD 177423
spect
B5II

About HD 177423

HD 177423 is a rare star. It lies about 1,583.3 light-years from Earth, sits in the constellation Sgr, shines at apparent magnitude 7.98 and has spectral type B5II.

Its spectrum reads B5II — 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 177423 in the constellation Sgr. At apparent magnitude 7.98, it is an easy target for binoculars.

Like any astronomical target, HD 177423 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 177423 is a rare star

HD 177423 scores 43 points on Spacedle's rarity scale, which places it in the rare tier. Another 7 points would lift it into a rarer tier.

That score comes from 7 science badges — Star, Distant (over 1,000 light-years), Toward the galactic centre, On the zodiac, Hot blue B-type star, Bright giant 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.