"radio astronomy." YourDictionary, n.d. Web. 17 October 2018. <http://www.yourdictionary.com/radio-astronomy>.
radio astronomy. (n.d.). Retrieved October 17th, 2018, from http://www.yourdictionary.com/radio-astronomy
The branch of astronomy that uses observations of emissions in the radio part of the electromagnetic spectrum to study extraterrestrial sources such as stars, planets, galaxies, interstellar gas, and dust clouds.