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Uncommon star 30 EP

Yildun

RA 263.0538° · Dec 86.5865° · star

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Score breakdown

· 6 badges
30 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Has a proper name +8
  • White A-type star +5
  • Never sets (northern circumpolar) +4
  • Star +3
  • Main-sequence star +2
Total score 30

4 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Has a proper name · +8
  • Never sets (northern circumpolar) · +4
  • White A-type star · +5
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads A1Vn — 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 4.3 you can see it with your own eyes from a dark site, over in Ursa Minor.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • 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. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.738
bv
0.021
constellation
UMi
dist ly
172.1138
luminosity
44.1367
mag
4.35
name
Yildun
named
yes
spect
A1Vn

About Yildun

Yildun is an uncommon star. It lies about 172.1 light-years from Earth, sits in the constellation UMi, shines at apparent magnitude 4.35 and has spectral type A1Vn.

Its spectrum reads A1Vn — 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 Yildun in the constellation UMi. At apparent magnitude 4.35, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, Yildun 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 Yildun is an uncommon star

Yildun scores 30 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 4 points would lift it into a rarer tier.

That score comes from 6 science badges — Star, Naked-eye visible, Has a proper name, Never sets (northern circumpolar), White A-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.