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Rare variable star 39 EP

HIP 100048

RA 304.4735° · Dec 59.7927° · star

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Dramatic variable (over 2 magnitudes) +20
  • Red dwarf +6
  • Variable star +5
  • Cool red M-type star +5
  • A named variable star +3
Total score 39

11 more points to reach Epic.

Badges

  • Variable star · +5
  • Cool red M-type star · +5
  • Red dwarf · +6
  • Dramatic variable (over 2 magnitudes) · +20
  • A named variable star · +3

Trivia

Hard to believe

  • True brightness. It pours out about 871 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 M2-M7E(S) — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • 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 10 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.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out orange (B−V 1.3) — 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 4130 K, against the Sun's 5778 K.

Properties

absmag
-10.02
bv
1.294
constellation
Cyg
luminosity
887156.012
mag
9.98
name
HIP 100048
spect
M2-M7E(S)
var amplitude
2.85
var designation
CN
var max
9.014
var min
11.864

About HIP 100048

HIP 100048 is a rare variable star. It sits in the constellation Cyg, shines at apparent magnitude 9.98 and has spectral type M2-M7E(S).

Its spectrum reads M2-M7E(S) — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.

How to see it

Look for HIP 100048 in the constellation Cyg. At apparent magnitude 9.98, a small backyard telescope will bring it into view.

Like any astronomical target, HIP 100048 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 100048 is a rare variable star

HIP 100048 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Cool red M-type star, Red dwarf, Dramatic variable (over 2 magnitudes) 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.