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Common variable star 17 EP

HD 136813

RA 232.7961° · Dec -78.7530° · star

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Score breakdown

· 5 badges
17 pts · Common
Common 22 pts → Uncommon
  • Variable star +5
  • Gently variable +4
  • Yellow-white F-type star +3
  • A named variable star +3
  • Main-sequence star +2
Total score 17

5 more points to reach Uncommon.

Badges

  • Variable star · +5
  • Yellow-white F-type star · +3
  • Main-sequence star · +2
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads F3V — 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.
  • 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 7.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Apus.
  • 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 May — that's when to go looking.

Could we get there?

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

Properties

absmag
2.071
bv
0.394
constellation
Aps
dist ly
471.3238
luminosity
12.93
mag
7.87
name
HD 136813
spect
F3V
var amplitude
0.08
var designation
PS
var max
7.846
var min
7.926

About HD 136813

HD 136813 is a common variable star. It lies about 471.3 light-years from Earth, sits in the constellation Aps, shines at apparent magnitude 7.87 and has spectral type F3V.

Its spectrum reads F3V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 136813 in the constellation Aps. At apparent magnitude 7.87, it is an easy target for binoculars.

Like any astronomical target, HD 136813 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 136813 is a common variable star

HD 136813 scores 17 points on Spacedle's rarity scale, which places it in the common tier. Another 5 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Yellow-white F-type star, Main-sequence 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.