About HIP 19978
HIP 19978 is an uncommon variable star. It sits in the constellation Per, shines at apparent magnitude 11.22 and has spectral type G0.
Its spectrum reads G0 — a G-type star: the very same spectral class as our own Sun.
Uncommon variable star 26 EP
HIP 19978
RA 64.2753° · Dec 41.7318° · star
Score breakdown
· 4 badgesUncommon 34 pts → Rare
- Strongly variable +10
- Sun-like G-type star +8
- Variable star +5
- A named variable star +3
Total score 26
8 more points to reach Rare.
Badges
- Variable star · +5
- Sun-like G-type star · +8
- Strongly variable · +10
- A named variable star · +3
Trivia
Hard to believe
- True brightness. It pours out about 278 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 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.
Find it in the sky
- How to spot it. At magnitude 11.2 you'll want a small backyard telescope, over in Perseus.
- 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 November — 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.
How we came to know it
- Cosmic yardstick. Variable stars are how we measured the universe. In 1912 Henrietta Leavitt showed that a pulsating star's rhythm reveals its true brightness — turning these stars into distance markers.
Properties
- absmag
- -8.78
- constellation
- Per
- luminosity
- 283139.1996
- mag
- 11.22
- name
- HIP 19978
- spect
- G0
- var amplitude
- 0.82
- var designation
- SX
- var max
- 10.714
- var min
- 11.534
How to see it
Look for HIP 19978 in the constellation Per. At apparent magnitude 11.22, a small backyard telescope will bring it into view.
Like any astronomical target, HIP 19978 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 19978 is an uncommon variable star
HIP 19978 scores 26 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 8 points would lift it into a rarer tier.
That score comes from 4 science badges — Variable star, 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.