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Rare variable star 44 EP

HD 30593

RA 71.8289° · Dec -36.2093° · star

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Score breakdown

· 5 badges
44 pts · Rare
Rare 50 pts → Epic
  • Carbon star (sooty red) +24
  • Deep red star +8
  • Variable star +5
  • Gently variable +4
  • A named variable star +3
Total score 44

6 more points to reach Epic.

Badges

  • Variable star · +5
  • Carbon star (sooty red) · +24
  • Deep red star · +8
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads C — a carbon star, wrapped in so much soot that its light is filtered to a deep ruby red.
  • 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 7.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Caelum.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around December — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out deep orange-red (B−V 2.4) — one of the coolest surfaces a star can have while still fusing.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 2810 K, against the Sun's 5778 K.

What's in a name

  • Its catalogue. The HD number is from the Henry Draper Catalogue, in which Annie Jump Cannon personally classified the spectra of nearly 400,000 stars — still the largest such feat by one person.

Properties

absmag
-12.34
bv
2.391
constellation
Cae
luminosity
7516228.9402
mag
7.66
name
HD 30593
spect
C
var amplitude
0.28
var designation
T
var max
7.516
var min
7.796

About HD 30593

HD 30593 is a rare variable star. It sits in the constellation Cae, shines at apparent magnitude 7.66 and has spectral type C.

Its spectrum reads C — a carbon star, wrapped in so much soot that its light is filtered to a deep ruby red.

How to see it

Look for HD 30593 in the constellation Cae. At apparent magnitude 7.66, it is an easy target for binoculars.

Like any astronomical target, HD 30593 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 30593 is a rare variable star

HD 30593 scores 44 points on Spacedle's rarity scale, which places it in the rare tier. Another 6 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Carbon star (sooty red), Deep red 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.