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Uncommon star 22 EP

31 Tau

RA 58.0010° · Dec 6.5349° · star

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Score breakdown

· 5 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Hot blue B-type star +6
  • Star +3
  • On the zodiac +3
  • Main-sequence star +2
Total score 22

12 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • On the zodiac · +3
  • Hot blue B-type star · +6
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads B5V — 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.

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 Taurus.
  • 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 November — 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. ≈ 13.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.229
bv
0.046
constellation
Tau
dist ly
778.4153
luminosity
270.1469
mag
5.66
name
31 Tau
spect
B5V

About 31 Tau

31 Tau is an uncommon star. It lies about 778.4 light-years from Earth, sits in the constellation Tau, shines at apparent magnitude 5.66 and has spectral type B5V.

Its spectrum reads B5V — 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 31 Tau in the constellation Tau. At apparent magnitude 5.66, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 31 Tau 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 31 Tau is an uncommon star

31 Tau scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Naked-eye visible, On the zodiac, Hot blue B-type star and Main-sequence 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.