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Trash star 8 EP

HD 17791

RA 42.8349° · Dec 2.1728° · star

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Score breakdown

· 3 badges
8 pts · Trash
Trash 15 pts → Common
  • Star +3
  • Orange K-type star +3
  • Main-sequence star +2
Total score 8

7 more points to reach Common.

Badges

  • Star · +3
  • Orange K-type star · +3
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads K5V — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.
  • Where it is in life. It is on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

Find it in the sky

  • How to spot it. At magnitude 7.1 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cetus.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around November — 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 4320 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
-12.88
bv
1.192
constellation
Cet
luminosity
12359474.3344
mag
7.12
name
HD 17791
spect
K5V

Nearby objects

About HD 17791

HD 17791 is a trash star. It sits in the constellation Cet, shines at apparent magnitude 7.12 and has spectral type K5V.

Its spectrum reads K5V — 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 17791 in the constellation Cet. At apparent magnitude 7.12, it is an easy target for binoculars.

Like any astronomical target, HD 17791 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 17791 is a trash star

HD 17791 scores 8 points on Spacedle's rarity scale, which places it in the trash tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, Orange K-type star and Main-sequence 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.