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Rare star 34 EP

HD 173357

RA 281.6643° · Dec -39.7309° · star

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Score breakdown

· 5 badges
34 pts · Rare
Rare 50 pts → Epic
  • Bright giant +12
  • Deep red star +8
  • Distant (over 1,000 light-years) +6
  • Cool red M-type star +5
  • Star +3
Total score 34

16 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Cool red M-type star · +5
  • Bright giant · +12
  • Deep red star · +8

Trivia

What it actually is

  • Spectral class. Its spectrum reads M2/M3II/III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.

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 6.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Corona Australis.
  • 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. ≈ 28.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 2.5 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-1.604
bv
1.613
constellation
CrA
dist ly
1622.6665
luminosity
381.5926
mag
6.88
name
HD 173357
spect
M2/M3II/III

About HD 173357

HD 173357 is a rare star. It lies about 1,622.7 light-years from Earth, sits in the constellation CrA, shines at apparent magnitude 6.88 and has spectral type M2/M3II/III.

Its spectrum reads M2/M3II/III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.

How to see it

Look for HD 173357 in the constellation CrA. At apparent magnitude 6.88, it is an easy target for binoculars.

Like any astronomical target, HD 173357 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 173357 is a rare star

HD 173357 scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Distant (over 1,000 light-years), Cool red M-type star, Bright giant and Deep red 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.