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Rare variable star 41 EP

HD 101724

RA 175.4794° · Dec -63.7954° · star

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Score breakdown

· 7 badges
41 pts · Rare
Rare 50 pts → Epic
  • Bright giant +12
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Variable star +5
  • Blue-white star +5
  • Gently variable +4
  • A named variable star +3
Total score 41

9 more points to reach Epic.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Bright giant · +12
  • Blue-white star · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9II/III — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
  • 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 8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Centaurus.
  • 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 March — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

absmag
0.134
bv
-0.009
constellation
Cen
dist ly
1226.1502
luminosity
76.9839
mag
8.01
name
HD 101724
spect
B9II/III
var amplitude
0.07
var designation
V915
var max
7.988
var min
8.058

About HD 101724

HD 101724 is a rare variable star. It lies about 1,226.2 light-years from Earth, sits in the constellation Cen, shines at apparent magnitude 8.01 and has spectral type B9II/III.

Its spectrum reads B9II/III — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for HD 101724 in the constellation Cen. At apparent magnitude 8.01, it is an easy target for binoculars.

Like any astronomical target, HD 101724 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 101724 is a rare variable star

HD 101724 scores 41 points on Spacedle's rarity scale, which places it in the rare tier. Another 9 points would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Distant (over 1,000 light-years), Hot blue B-type star, Bright giant, 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.