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Common star 15 EP

HD 173491

RA 283.4280° · Dec -74.9583° · star

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Score breakdown

· 4 badges
15 pts · Common
Common 22 pts → Uncommon
  • White A-type star +5
  • Blue-white star +5
  • Star +3
  • Main-sequence star +2
Total score 15

7 more points to reach Uncommon.

Badges

  • Star · +3
  • White A-type star · +5
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads A0V — 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.
  • 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 7.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Octans.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • 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. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 9.6 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.286
bv
-0.035
constellation
Oct
dist ly
547.2415
luminosity
26.644
mag
7.41
name
HD 173491
spect
A0V

About HD 173491

HD 173491 is a common star. It lies about 547.2 light-years from Earth, sits in the constellation Oct, shines at apparent magnitude 7.41 and has spectral type A0V.

Its spectrum reads A0V — 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 173491 in the constellation Oct. At apparent magnitude 7.41, it is an easy target for binoculars.

Like any astronomical target, HD 173491 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 173491 is a common star

HD 173491 scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, White A-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.