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Uncommon variable star 32 EP

HD 307739

RA 156.2484° · Dec -63.6362° · star

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Score breakdown

· 5 badges
32 pts · Uncommon
Uncommon 34 pts → Rare
  • Strongly variable +10
  • Sun-like G-type star +8
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • A named variable star +3
Total score 32

2 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Sun-like G-type star · +8
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads G0 — a G-type star: the very same spectral class as our own Sun.
  • 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 11.1 you'll want a small backyard telescope, over in Carina.
  • 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 February — 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. ≈ 43.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.716
bv
0.202
constellation
Car
dist ly
2489.7405
luminosity
17.9308
mag
11.13
name
HD 307739
spect
G0
var amplitude
0.56
var designation
EX
var max
11.009
var min
11.569

About HD 307739

HD 307739 is an uncommon variable star. It lies about 2,489.7 light-years from Earth, sits in the constellation Car, shines at apparent magnitude 11.13 and has spectral type G0.

Its spectrum reads G0 — a G-type star: the very same spectral class as our own Sun.

How to see it

Look for HD 307739 in the constellation Car. At apparent magnitude 11.13, a small backyard telescope will bring it into view.

Like any astronomical target, HD 307739 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 307739 is an uncommon variable star

HD 307739 scores 32 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 2 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Distant (over 1,000 light-years), Sun-like G-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.