April 2026

It takes three communications satellites to send a signal right around the Earth. Radio waves travel at the speed of light, 299,792 km (186,287 miles) per second, so it takes less than a second for your voice in a telephone call to go from Britain to Australia.

Landsat. The first space agency NASA launched the first Landsat satellite in 1972. Landsats are observation satellites and the photos they beam back to Earth are used for accurate map-making and the study of the world’s oceans, forests and rivers. They can help to keep track of forest fires, oil spills and other ecological disasters.

Intelsat 7.  This is a comsat (communications satellite) which receives and sends thousands of telephone calls, faxes, TV pictures with sound, items of computer data and telexes. Comsats help people to communicate across the world, but within countries. Indonesia’s first satellite, Palapa 1, connected by radio, TV and telephone 200 million people living on more than 6000 islands.

Borrowed by Daheap from Reader’s Digest Book of Amazing Facts 2000.