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Rare variable star 35 EP

HR 4333

RA 167.3295° · Dec 36.3094° · star

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Score breakdown

· 7 badges
35 pts · Rare
Rare 50 pts → Epic
  • Naked-eye visible +8
  • Giant star +6
  • Variable star +5
  • Cool red M-type star +5
  • Never sets (northern circumpolar) +4
  • Gently variable +4
  • A named variable star +3
Total score 35

15 more points to reach Epic.

Badges

  • Variable star · +5
  • Naked-eye visible · +8
  • Never sets (northern circumpolar) · +4
  • Cool red M-type star · +5
  • Giant star · +6
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M3.5III — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • Where it is in life. It is a giant. It has already exhausted its core hydrogen and swollen up enormously in response.
  • 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 5.7 you can see it with your own eyes from a dark site, over in Ursa Major.
  • 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 March — that's when to go looking.

Could we get there?

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

Properties

absmag
0.367
bv
1.4
constellation
UMa
dist ly
381.9156
luminosity
62.1155
mag
5.71
name
HR 4333
spect
M3.5III
var amplitude
0.17
var designation
CO
var max
5.649
var min
5.819

About HR 4333

HR 4333 is a rare variable star. It lies about 381.9 light-years from Earth, sits in the constellation UMa, shines at apparent magnitude 5.71 and has spectral type M3.5III.

Its spectrum reads M3.5III — 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 HR 4333 in the constellation UMa. At apparent magnitude 5.71, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 4333 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 HR 4333 is a rare variable star

HR 4333 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 7 science badges — Variable star, Naked-eye visible, Never sets (northern circumpolar), Cool red M-type star, Giant star, 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.