Uncommon variable star 33 EP

HIP 99599

RA 303.1880° · Dec 47.3948° · star

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Score breakdown

· 5 badges

33 pts · Uncommon

Uncommon 34 pts → Rare

Supergiant +18
Variable star +5
Gently variable +4
Yellow-white F-type star +3
A named variable star +3

Total score 33

1 more point to reach Rare.

Badges

Variable star · +5
Yellow-white F-type star · +3
Supergiant · +18
Gently variable · +4
A named variable star · +3

Trivia

Hard to believe

True brightness. It pours out about 343.6 thousand 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 F4Ia comp — 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 11 you'll want a small backyard telescope, over in Cygnus.
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.

What's in a name

Its catalogue. The HIP number comes from Hipparcos, the ESA satellite that between 1989 and 1993 pinned down 118,000 stars precisely enough to triangulate their distances.

Properties

absmag: -9.01
constellation: Cyg
luminosity: 349945.167
mag: 10.99
name: HIP 99599
spect: F4Ia comp
var amplitude: 0.45
var designation: KU
var max: 10.879
var min: 11.329

Nearby objects

About HIP 99599

HIP 99599 is an uncommon variable star. It sits in the constellation Cyg, shines at apparent magnitude 10.99 and has spectral type F4Ia comp.

Its spectrum reads F4Ia comp — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HIP 99599 in the constellation Cyg. At apparent magnitude 10.99, a small backyard telescope will bring it into view.

Like any astronomical target, HIP 99599 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 HIP 99599 is an uncommon variable star

HIP 99599 scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

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