Apparent magnitude is a measurement used to indicate the brightness of a star in the sky. The smaller the number, the brighter the object. The faintest visible objects seen by giant telescopes have a magnitude of +30. A good portable amateur telescope can see objects to a magnitude of +15. With binoculars, objects of magnitude +9 can be seen and the faintest objects visible to the naked eye have a magnitude of +6. Very bright objects have a negative magnitude, with the brightest stars having a magnitude of -1.4, the full Moon -12.7 and the midday Sun -26.8.