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Uncommon variable star 30 EP

HR 8919

RA 352.2540° · Dec -63.1107° · star

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Score breakdown

· 6 badges
30 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Variable star +5
  • White A-type star +5
  • Blue-white star +5
  • Gently variable +4
  • A named variable star +3
Total score 30

4 more points to reach Rare.

Badges

  • Variable star · +5
  • Naked-eye visible · +8
  • White A-type star · +5
  • Blue-white star · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads Ap Si — 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.
  • It changes. This star does not hold still: its brightness rises and falls on a rhythm of hours, days or years, either pulsing in size or being eclipsed by a companion.

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 5.7 you can see it with your own eyes from a dark site, over in Tucana.
  • 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 September — 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. ≈ 6.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.292
bv
-0.142
constellation
Tuc
dist ly
386.4407
luminosity
66.558
mag
5.66
name
HR 8919
spect
Ap Si
var amplitude
0.05
var designation
CG
var max
5.629
var min
5.679

About HR 8919

HR 8919 is an uncommon variable star. It lies about 386.4 light-years from Earth, sits in the constellation Tuc, shines at apparent magnitude 5.66 and has spectral type Ap Si.

Its spectrum reads Ap Si — 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 HR 8919 in the constellation Tuc. At apparent magnitude 5.66, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 8919 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 HR 8919 is an uncommon variable star

HR 8919 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 — Variable star, Naked-eye visible, White A-type star, Blue-white star, Gently variable and A named variable 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.