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Rare variable star 35 EP

HD 103154

RA 178.1879° · Dec -7.5967° · star

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Score breakdown

· 6 badges
35 pts · Rare
Rare 50 pts → Epic
  • Strongly variable +10
  • Distant (over 1,000 light-years) +6
  • Red dwarf +6
  • Variable star +5
  • Cool red M-type star +5
  • A named variable star +3
Total score 35

15 more points to reach Epic.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Cool red M-type star · +5
  • Red dwarf · +6
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M6e-M7e — 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.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 9.2 you'll want a small backyard telescope, over in Crater.
  • 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 March — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 45.5 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.298
bv
1.078
constellation
Crt
dist ly
2588.5397
luminosity
114.6041
mag
9.2
name
HD 103154
spect
M6e-M7e
var amplitude
0.52
var designation
S
var max
8.913
var min
9.433

About HD 103154

HD 103154 is a rare variable star. It lies about 2,588.5 light-years from Earth, sits in the constellation Crt, shines at apparent magnitude 9.2 and has spectral type M6e-M7e.

Its spectrum reads M6e-M7e — 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 103154 in the constellation Crt. At apparent magnitude 9.2, a small backyard telescope will bring it into view.

Like any astronomical target, HD 103154 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 103154 is a rare variable star

HD 103154 scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Distant (over 1,000 light-years), Cool red M-type star, Red dwarf, 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.