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Rare star 35 EP

Mu 1Cru

RA 193.6485° · Dec -57.1779° · star

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Score breakdown

· 6 badges
35 pts · Rare
Rare 50 pts → Epic
  • Naked-eye visible +8
  • Under the Southern Cross +8
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Blue-white star +5
  • Star +3
Total score 35

15 more points to reach Epic.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Under the Southern Cross · +8
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2IV-V — 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 a subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.

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 you can see it with your own eyes from a dark site, over in Crux.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around April — 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. ≈ 7.3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.49
bv
-0.18
constellation
Cru
dist ly
414.4295
luminosity
343.5579
mag
4.03
name
Mu 1Cru
spect
B2IV-V

About Mu 1Cru

Mu 1Cru is a rare star. It lies about 414.4 light-years from Earth, sits in the constellation Cru, shines at apparent magnitude 4.03 and has spectral type B2IV-V.

Its spectrum reads B2IV-V — 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 Mu 1Cru in the constellation Cru. At apparent magnitude 4.03, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, Mu 1Cru 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 Mu 1Cru is a rare star

Mu 1Cru 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 — Star, Naked-eye visible, Under the Southern Cross, Hot blue B-type star, Subgiant (leaving the main sequence) and Blue-white 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.