← Back to dex
Rare variable star 34 EP

HD 241771

RA 78.4749° · Dec 17.4533° · star

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

Computing the sky for your location…

Score breakdown

· 7 badges
34 pts · Rare
Rare 50 pts → Epic
  • Deep red star +8
  • Red dwarf +6
  • Variable star +5
  • Cool red M-type star +5
  • Gently variable +4
  • On the zodiac +3
  • A named variable star +3
Total score 34

16 more points to reach Epic.

Badges

  • Variable star · +5
  • On the zodiac · +3
  • Cool red M-type star · +5
  • Deep red star · +8
  • Red dwarf · +6
  • Gently variable · +4
  • A named variable star · +3

Trivia

Hard to believe

  • True brightness. It pours out about 2.1 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 M2 — 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 9 you'll want a small backyard telescope, over in Taurus.
  • 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 December — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out deep orange-red (B−V 1.9) — one of the coolest surfaces a star can have while still fusing.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 3280 K, against the Sun's 5778 K.

Properties

absmag
-11
bv
1.898
constellation
Tau
luminosity
2187761.6239
mag
9
name
HD 241771
spect
M2
var amplitude
0.46
var designation
V1158
var max
8.837
var min
9.297

About HD 241771

HD 241771 is a rare variable star. It sits in the constellation Tau, shines at apparent magnitude 9 and has spectral type M2.

Its spectrum reads M2 — 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 HD 241771 in the constellation Tau. At apparent magnitude 9, it is an easy target for binoculars.

Like any astronomical target, HD 241771 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 241771 is a rare variable star

HD 241771 scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, On the zodiac, Cool red M-type star, Deep red star, Red dwarf, 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.