The magnitude scale is logarithmic, so a difference of one point in magnitude is equal to a difference in brightness of about 2.5 times.

A magnitude-one star is about 2.5 time brighter than a magnitude-two star, and a hundred times brighter than a magnitude-five star.

The lower the magnitude, the brighter the object.

The brighter planets and stars have negative magnitudes. The sun, the brightest object in the sky, has a magnitude of -26, followed by a full moon at magnitude -12.6.

Objects with a magnitude of six or less can be seen without optical aid under ideal observing conditions away from all artificial light.