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Common star 20 EP

HD 39478

RA 88.4994° · Dec 26.4225° · star

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Score breakdown

· 5 badges
20 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Star +3
  • On the zodiac +3
  • Main-sequence star +2
Total score 20

2 more points to reach Uncommon.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • On the zodiac · +3
  • Hot blue B-type star · +6
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2V — 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 8.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Taurus.
  • 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 December — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 41.5 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.051
bv
0.06
constellation
Tau
dist ly
2363.4493
luminosity
229.2979
mag
8.25
name
HD 39478
spect
B2V

About HD 39478

HD 39478 is a common star. It lies about 2,363.4 light-years from Earth, sits in the constellation Tau, shines at apparent magnitude 8.25 and has spectral type B2V.

Its spectrum reads B2V — 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 HD 39478 in the constellation Tau. At apparent magnitude 8.25, it is an easy target for binoculars.

Like any astronomical target, HD 39478 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 39478 is a common star

HD 39478 scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 2 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Distant (over 1,000 light-years), 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.