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Uncommon star 31 EP

HD 166423

RA 272.9473° · Dec -29.9350° · star

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Score breakdown

· 6 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Toward the galactic centre +8
  • Distant (over 1,000 light-years) +6
  • Giant star +6
  • White A-type star +5
  • Star +3
  • On the zodiac +3
Total score 31

3 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • White A-type star · +5
  • Giant star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads A8/A9III — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

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 9.7 you'll want a small backyard telescope, 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 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. ≈ 23.4 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 2.1 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
1.646
bv
0.467
constellation
Sgr
dist ly
1331.2491
luminosity
19.1249
mag
9.7
name
HD 166423
spect
A8/A9III

About HD 166423

HD 166423 is an uncommon star. It lies about 1,331.2 light-years from Earth, sits in the constellation Sgr, shines at apparent magnitude 9.7 and has spectral type A8/A9III.

Its spectrum reads A8/A9III — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

How to see it

Look for HD 166423 in the constellation Sgr. At apparent magnitude 9.7, a small backyard telescope will bring it into view.

Like any astronomical target, HD 166423 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 166423 is an uncommon star

HD 166423 scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 6 science badges — Star, Distant (over 1,000 light-years), Toward the galactic centre, On the zodiac, White A-type star and Giant 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.