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Uncommon variable star 31 EP

4The CrB

RA 233.2324° · Dec 31.3591° · star

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Score breakdown

· 7 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Hot blue B-type star +6
  • Variable star +5
  • Blue-white star +5
  • A named variable star +3
  • Main-sequence star +2
  • Barely variable (under 0.05 mag) +2
Total score 31

3 more points to reach Rare.

Badges

  • Variable star · +5
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5
  • Barely variable (under 0.05 mag) · +2
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B6Vnn — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
  • Where it is in life. It is on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.
  • 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 4.1 you can see it with your own eyes from a dark site, over in Corona Borealis.
  • 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 May — that's when to go looking.

Could we get there?

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

Properties

absmag
-1.165
bv
-0.127
constellation
CrB
dist ly
375.3234
luminosity
254.683
mag
4.14
name
4The CrB
spect
B6Vnn
var amplitude
0.02
var designation
The
var max
4.128
var min
4.148

About 4The CrB

4The CrB is an uncommon variable star. It lies about 375.3 light-years from Earth, sits in the constellation CrB, shines at apparent magnitude 4.14 and has spectral type B6Vnn.

Its spectrum reads B6Vnn — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for 4The CrB in the constellation CrB. At apparent magnitude 4.14, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 4The CrB 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 4The CrB is an uncommon variable star

4The CrB scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Naked-eye visible, Hot blue B-type star, Main-sequence star, Blue-white star, Barely variable (under 0.05 mag) 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.