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Stellar magnitude scale visualizer

Each magnitude step ≈ 2.512× brighter · A 5-magnitude difference = exactly 100× brighter

How the magnitude scale works

The scale was set in the second century BCE by Hipparchus, who ranked the brightest stars as first magnitude and the faintest visible as sixth. In 1856 Norman Pogson tied the system to a precise ratio: each magnitude step equals exactly the fifth root of 100 — about 2.512. Five magnitudes is exactly 100× in brightness.

Reference values

  • Sun: −26.74
  • Full Moon: −12.74
  • Venus at brightest: −4.92
  • Sirius: −1.46 (brightest star)
  • Polaris: +1.97
  • Naked-eye limit (dark sky): +6.5
  • Binoculars (50 mm): +10
  • Hubble deepest images: +31

Apparent vs absolute

The numbers above are apparent magnitudes — how bright the object looks from Earth. Absolute magnitude normalizes this to a standard distance of 10 parsecs, letting you compare intrinsic luminosities. The Sun's apparent magnitude is −26.74, but its absolute magnitude is +4.83 — fairly average for a main-sequence star.