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Rare variable star 39 EP

HD 339279

RA 299.3692° · Dec 26.5565° · star

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Supergiant +18
  • Strongly variable +10
  • Variable star +5
  • Yellow-white F-type star +3
  • A named variable star +3
Total score 39

11 more points to reach Epic.

Badges

  • Variable star · +5
  • Yellow-white F-type star · +3
  • Supergiant · +18
  • Strongly variable · +10
  • A named variable star · +3

Trivia

Hard to believe

  • True brightness. It pours out about 2.4 million times as much light as the Sun. It only looks ordinary because it is so far away.

What it actually is

  • Spectral class. Its spectrum reads F8Ia — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • Where it is in life. It is a luminous supergiant — among the largest and rarest stars in the galaxy.
  • 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.

Find it in the sky

  • How to spot it. At magnitude 8.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Vulpecula.
  • 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.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out orange (B−V 1.3) — cooler than the Sun, and the kind of star that burns steadily for tens of billions of years.

Properties

absmag
-11.13
bv
1.278
constellation
Vul
luminosity
2466039.3372
mag
8.87
name
HD 339279
spect
F8Ia
var amplitude
0.74
var designation
X
var max
8.542
var min
9.282

About HD 339279

HD 339279 is a rare variable star. It sits in the constellation Vul, shines at apparent magnitude 8.87 and has spectral type F8Ia.

Its spectrum reads F8Ia — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 339279 in the constellation Vul. At apparent magnitude 8.87, it is an easy target for binoculars.

Like any astronomical target, HD 339279 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 339279 is a rare variable star

HD 339279 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

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