The aluminum-domed Crosby Observatory atop Orlando Science Center houses Florida's largest publicly accessible refractor telescope. This one-of-a-kind custom-built telescope, along with several smaller scopes, are available at selected times for solar and night sky viewing.
Peer through the powerful, 10-inch lens of the refractor telescope to view the planets, the four moons of Jupiter, the rings of Saturn and deep sky objects such as galaxies, nebulas and double stars.
All activities and events in the Crosby Observatory
are weather permitting only.
June 13 - August 16, 2014
Every Friday & Saturday Evening, 8:00 - 11:00 p.m.
Join our astronomers in the Crosby Observatory for a night full of wonder. Enjoy views of the celestial objects while you take in the glittering Orlando skyline. Our telescopes will expand your horizons to places like Jupiter, Mars and Venus and beyond.
Science Night Live
Seasonal Event: Please Check Events Calendar
An “adult swim” of the science variety, the event features everything great about the Science Center. Experience all four floors of exhibits, films and hands-on programming aimed specifically for grown-ups, while enjoying adult food and beverages available for purchase. Must be 21 and older.
04 November 2010
Posted in Crosby Observatory
Measuring and evaluating the brightness of stars can be traced back to the Greek astronomer and mathematician Hipparchus during 190 - 120 BC. He is responsible for producing a catalogue of comparative brightness and positioning of over 850 stars. Hipparchus formed the apparent magnitude scale to determine the brightness of a star as seen by an observer from earth.
How does this scale work? The brighter the celestial object appears, the lower the value of its magnitude. For instance, the faintest objects you can see using the naked eye are indicated with a magnitude of 6, while the Sun on the apparent magnitude scale is –26.74. However, most of the stars we gaze at in an urban neighborhood with our eyes are usually somewhere around 3 to 4 and if using binoculars, the limit is 10. More recently, through the use of the powerful Hubble Space Telescope, astronomers have located stars with magnitudes of 30+. It is this basic classification from over 2,000 years ago that led to the magnitude scale that we still use today!