Syndicated from the original on lkforge.com. The ranking below is printed by one short, dependency-free script.
The North Star is the most famous star in the sky, and almost everyone assumes fame means brightness. It doesn't. Rank the stars by how bright they actually appear and Polaris isn't close to the top - it isn't even in the top forty.
The correction
- Polaris ranks about 48th in apparent brightness.
- The real brightest star, Sirius (magnitude -1.46), outshines Polaris (+1.98) by roughly 24 to 1.
- Polaris shines at only 4.2% of Sirius, beaten by two dozen household-name stars before you even reach the fainter ones.
The actual brightest stars (as a share of Sirius)
| # | Star | Brightness vs Sirius |
|---|---|---|
| 1 | Sirius | 100% |
| 2 | Canopus | 52% |
| 3 | Alpha Centauri | 33% |
| 4 | Arcturus | 27% |
| 5 | Vega | 25% |
| 6 | Capella | 24% |
| 7 | Rigel | 23% |
| 8 | Procyon | 19% |
| 9 | Betelgeuse | 18% |
| ... | ...(35+ more) | ... |
| ~48 | Polaris | 4.2% |
Why the numbers run backwards
The scale is the confusing part. Apparent magnitude measures brightness with smaller = brighter - a leftover from the ancient Greeks, who called the brightest stars "first magnitude" and the faintest "sixth." It's also logarithmic: every 5 steps of magnitude is a factor of exactly 100 in brightness.
So Sirius at -1.46 is genuinely brilliant, Polaris at +1.98 is middling, and a magnitude-6 star is at the edge of naked-eye visibility. To turn magnitudes into a linear "how many times brighter," you use:
brightness ratio = 10 ^ (-0.4 * delta-magnitude)
For Sirius vs Polaris that's a gap of ~3.44 magnitudes, or about 24x.
So why is Polaris famous?
Position, not brightness. Polaris sits within about 0.7 degrees of the north celestial pole - the point Earth's axis points at - so as the planet turns, every other star wheels in a circle while Polaris barely moves. It marks true north and holds still, which for two thousand years made it the single most useful star for navigation in the Northern Hemisphere.
It won't hold the job forever: Earth's axis slowly wobbles (precession), so the pole star changes over millennia - the bright star Vega sat near the pole around 12,000 BC and will again near 13,700 AD. Polaris is simply the star on duty now.
Reproduce it
Every figure comes from one short script: standard published apparent magnitudes (Hipparcos / Yale Bright Star Catalogue), ranked, then converted to linear brightness. Several bright stars are slightly variable, so ranks near a tie can shift a place; Polaris's ~48th is the widely cited figure.
Full write-up with the ranked chart is on the original: Is the North Star the Brightest? You can find Polaris and everything wheeling around it with the Sky Explorer.
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