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Common variable star 15 EP

15 CMa

RA 103.3871° · Dec -20.2243° · star

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Score breakdown

· 2 badges
15 pts · Common
Common 24 pts → Uncommon
  • Distant (>1000 ly) +10
  • Variable star +5
Total score 15

9 more points to reach Uncommon.

Badges

  • Variable star · +5
  • Distant (>1000 ly) · +10

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 21.4 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.9 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 12.2 thousand years in a starship at a tenth of light speed.
  • Distance. 1217 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 809.

Saying hello

  • Say hello. A radio message and its reply would take 2434 years round-trip.

Properties

absmag
-3.039
bv
-0.212
constellation
CMa
dist ly
1216.9999
mag
4.82
name
15 CMa
spect
B1Ib

About 15 CMa

15 CMa is a common variable star. It lies about 1,217 light-years from Earth, sits in the constellation CMa, shines at apparent magnitude 4.82 and has spectral type B1Ib.

15 CMa is a common variable star worth 15 points across 2 science badges. Explore its facts, badges and place on the sky map, then add it to your dex on Spacedle.

How to see it

Look for 15 CMa in the constellation CMa. At apparent magnitude 4.82, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 15 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 15 CMa is a common variable star

15 CMa scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 9 points would lift it into a rarer tier.

That score comes from 2 science badges — Variable star and Distant (>1000 ly) — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.