← Back to dex
Common star 15 EP

HD 222734

RA 355.8267° · Dec -21.0902° · star

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 4 badges
15 pts · Common
Common 22 pts → Uncommon
  • Giant star +6
  • Star +3
  • On the zodiac +3
  • Orange K-type star +3
Total score 15

7 more points to reach Uncommon.

Badges

  • Star · +3
  • On the zodiac · +3
  • Orange K-type star · +3
  • Giant star · +6

Trivia

Hard to believe

  • True brightness. It pours out about 3.2 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 K1/K2III — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.

Find it in the sky

  • How to spot it. At magnitude 8.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Aquarius.
  • 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 September — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out orange (B−V 1.2) — cooler than the Sun, and the kind of star that burns steadily for tens of billions of years.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 4280 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
-11.44
bv
1.217
constellation
Aqr
luminosity
3280952.9311
mag
8.56
name
HD 222734
spect
K1/K2III

About HD 222734

HD 222734 is a common star. It sits in the constellation Aqr, shines at apparent magnitude 8.56 and has spectral type K1/K2III.

Its spectrum reads K1/K2III — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.

How to see it

Look for HD 222734 in the constellation Aqr. At apparent magnitude 8.56, it is an easy target for binoculars.

Like any astronomical target, HD 222734 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 222734 is a common star

HD 222734 scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, On the zodiac, Orange K-type star and Giant 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.