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Uncommon variable star 23 EP

HD 159829

RA 265.7695° · Dec -70.8727° · star

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Score breakdown

· 5 badges
23 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • White A-type star +5
  • Gently variable +4
  • A named variable star +3
Total score 23

11 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • White A-type star · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads A3mA5-A8 — 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 9.7 you'll want a small backyard telescope, 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 June — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 28.5 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.206
bv
0.288
constellation
Aps
dist ly
1622.6665
luminosity
28.6814
mag
9.69
name
HD 159829
spect
A3mA5-A8
var amplitude
0.25
var designation
PP
var max
9.628
var min
9.878

About HD 159829

HD 159829 is an uncommon variable star. It lies about 1,622.7 light-years from Earth, sits in the constellation Aps, shines at apparent magnitude 9.69 and has spectral type A3mA5-A8.

Its spectrum reads A3mA5-A8 — 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 159829 in the constellation Aps. At apparent magnitude 9.69, a small backyard telescope will bring it into view.

Like any astronomical target, HD 159829 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 159829 is an uncommon variable star

HD 159829 scores 23 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Distant (over 1,000 light-years), White A-type 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.