- (informal) Astronomy using observations using telescopes and recording media that capture visible light.
1958 September 28, “Radio to Extend Astronomy's Ears”, in New York Times:
- Radio astronomy is an extension of optical astronomy in the that it allows the observer to "see radiations of wave lengths far greater than those of visible light
1966 March 11, Time Magazine:
- Merely finding them in the first place — detecting their radio voices and photographing their odd and telltale light — was a cooperative triumph of radio and optical astronomy.
2006, Peter Schneider, Extragalactic astronomy and cosmology, page 25:
- Since for the atmospheric windows in the NIR one normally uses the same telescopes as for optical astronomy, we will thus not distinguish between these
2009 June 16, “Cosmic vision”, in Frontline:
- Because each kind of light reveals different natural phenomena, we see only a part of nature. The same is true of telescopes. Optical telescopes detect only visible light. ... Dust is the bane of optical astronomy.
- (astronomy) Astronomy using infrared, visible, and/or ultraviolet wavelengths.