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Uncommon variable star 26 EP

HD 78420

RA 137.1106° · Dec 13.2205° · star

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Score breakdown

· 6 badges
26 pts · Uncommon
Uncommon 34 pts → Rare
  • 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 26

8 more points to reach Rare.

Badges

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

Trivia

What it actually is

  • Spectral class. Its spectrum reads M6 — 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 Cancer.
  • 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 February — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 14 million years at Voyager 1's speed (17 km/s).

Properties

absmag
2.259
bv
1.113
constellation
Cnc
dist ly
797.4475
luminosity
10.8743
mag
9.2
name
HD 78420
spect
M6
var amplitude
0.32
var designation
CW
var max
8.989
var min
9.309

About HD 78420

HD 78420 is an uncommon variable star. It lies about 797.4 light-years from Earth, sits in the constellation Cnc, shines at apparent magnitude 9.2 and has spectral type M6.

Its spectrum reads M6 — 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 78420 in the constellation Cnc. At apparent magnitude 9.2, a small backyard telescope will bring it into view.

Like any astronomical target, HD 78420 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 78420 is an uncommon variable star

HD 78420 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 6 science badges — Variable star, On the zodiac, Cool red M-type 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.