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Uncommon star 25 EP

HD 171789

RA 279.5140° · Dec -31.3599° · star

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Score breakdown

· 6 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Toward the galactic centre +8
  • Distant (over 1,000 light-years) +6
  • Star +3
  • On the zodiac +3
  • Yellow-white F-type star +3
  • Main-sequence star +2
Total score 25

9 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • Yellow-white F-type star · +3
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads F5V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • 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 9.8 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. ≈ 53.1 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.013
bv
0.65
constellation
Sgr
dist ly
3019.9629
luminosity
88.1455
mag
9.82
name
HD 171789
spect
F5V

About HD 171789

HD 171789 is an uncommon star. It lies about 3,020 light-years from Earth, sits in the constellation Sgr, shines at apparent magnitude 9.82 and has spectral type F5V.

Its spectrum reads F5V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 171789 in the constellation Sgr. At apparent magnitude 9.82, a small backyard telescope will bring it into view.

Like any astronomical target, HD 171789 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 171789 is an uncommon star

HD 171789 scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 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, Yellow-white F-type star and Main-sequence 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.