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Uncommon variable star 29 EP

HD 239124

RA 293.1219° · Dec 56.3882° · star

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Score breakdown

· 5 badges
29 pts · Uncommon
Uncommon 34 pts → Rare
  • Strongly variable +10
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • White A-type star +5
  • A named variable star +3
Total score 29

5 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • White A-type star · +5
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads A9 — 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 9.9 you'll want a small backyard telescope, over in Cygnus.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around July — 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. ≈ 25 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.669
bv
0.25
constellation
Cyg
dist ly
1424.2619
luminosity
18.7241
mag
9.87
name
HD 239124
spect
A9
var amplitude
1.14
var designation
XZ
var max
8.977
var min
10.117

About HD 239124

HD 239124 is an uncommon variable star. It lies about 1,424.3 light-years from Earth, sits in the constellation Cyg, shines at apparent magnitude 9.87 and has spectral type A9.

Its spectrum reads A9 — 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 239124 in the constellation Cyg. At apparent magnitude 9.87, a small backyard telescope will bring it into view.

Like any astronomical target, HD 239124 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 239124 is an uncommon variable star

HD 239124 scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 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, Strongly 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.