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Common star 18 EP

17 CMa

RA 103.7614° · Dec -20.4049° · star

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Score breakdown

· 4 badges
18 pts · Common
Common 22 pts → Uncommon
  • Naked-eye visible +8
  • White A-type star +5
  • Star +3
  • Main-sequence star +2
Total score 18

4 more points to reach Uncommon.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • White A-type star · +5
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads A2V — 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.
  • 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 5.8 you can see it with your own eyes from a dark site, over in Canis Major.
  • 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 January — 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. ≈ 8.9 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.145
bv
0.048
constellation
CMa
dist ly
504.1051
luminosity
99.5405
mag
5.8
name
17 CMa
spect
A2V

About 17 CMa

17 CMa is a common star. It lies about 504.1 light-years from Earth, sits in the constellation CMa, shines at apparent magnitude 5.8 and has spectral type A2V.

Its spectrum reads A2V — 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 17 CMa in the constellation CMa. At apparent magnitude 5.8, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 17 CMa 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 17 CMa is a common star

17 CMa scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Naked-eye visible, White A-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.