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Common star 20 EP

HD 40166

RA 89.3757° · Dec 6.3912° · star

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Score breakdown

· 4 badges
20 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • In Orion's hunting ground +6
  • White A-type star +5
  • Star +3
Total score 20

2 more points to reach Uncommon.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • In Orion's hunting ground · +6
  • White A-type star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads A0 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

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 8.3 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Orion.
  • 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 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. ≈ 39.8 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 3.5 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-0.928
bv
0.034
constellation
Ori
dist ly
2264.9721
luminosity
204.7387
mag
8.28
name
HD 40166
spect
A0

About HD 40166

HD 40166 is a common star. It lies about 2,265 light-years from Earth, sits in the constellation Ori, shines at apparent magnitude 8.28 and has spectral type A0.

Its spectrum reads A0 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

How to see it

Look for HD 40166 in the constellation Ori. At apparent magnitude 8.28, it is an easy target for binoculars.

Like any astronomical target, HD 40166 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 40166 is a common star

HD 40166 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 4 science badges — Star, Distant (over 1,000 light-years), In Orion's hunting ground and White A-type 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.