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Rare variable star 37 EP

HD 105513

RA 182.2261° · Dec -55.7282° · star

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Score breakdown

· 6 badges
37 pts · Rare
Rare 50 pts → Epic
  • Bright giant +12
  • Under the Southern Cross +8
  • Variable star +5
  • White A-type star +5
  • Gently variable +4
  • A named variable star +3
Total score 37

13 more points to reach Epic.

Badges

  • Variable star · +5
  • Under the Southern Cross · +8
  • White A-type star · +5
  • Bright giant · +12
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads A8II/IIIw — 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 a bright giant, well on its way to the largest stars there are.
  • 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 9.3 you'll want a small backyard telescope, over in Crux.
  • 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 March — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Properties

absmag
1.892
bv
0.345
constellation
Cru
dist ly
979.4474
luminosity
15.2475
mag
9.28
name
HD 105513
spect
A8II/IIIw
var amplitude
0.11
var designation
CO
var max
9.228
var min
9.338

About HD 105513

HD 105513 is a rare variable star. It lies about 979.4 light-years from Earth, sits in the constellation Cru, shines at apparent magnitude 9.28 and has spectral type A8II/IIIw.

Its spectrum reads A8II/IIIw — 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 105513 in the constellation Cru. At apparent magnitude 9.28, a small backyard telescope will bring it into view.

Like any astronomical target, HD 105513 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 105513 is a rare variable star

HD 105513 scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Under the Southern Cross, White A-type star, Bright giant, 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.