On This Day in History - August 12, 1960
On August 12, 1960 NASA launched the world's first successful communications satellite from Cape Canaveral, Florida, the Echo 1. Earlier that year in May 1960, a similar but unsuccessful attempt by NASA to launch a nearly identical satellite failed to reach orbit. This first attempt was the maiden voyage of the Thor-Delta launch vehicle where attitude control jets on the Delta stage failed to ignite, sending the payload into the Atlantic Ocean instead of into orbit.
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On August 12, 1960 NASA launched the world's first successful communications satellite from Cape Canaveral, Florida, the Echo 1. Earlier that year in May 1960, a similar but unsuccessful attempt by NASA to launch a nearly identical satellite failed to reach orbit. This first attempt was the maiden voyage of the Thor-Delta launch vehicle where attitude control jets on the Delta stage failed to ignite, sending the payload into the Atlantic Ocean instead of into orbit.
The launch of Echo 1 laid the groundwork for modern satellite communications. In order to communicate with Echo 1, Bell labs created a 50 foot, horn shaped antenna. While calibrating the antenna, radio astronomers detected cosmic microwave background radiation, the first solid evidence of the Big Bang, for which they won the Nobel Prize. The Echo 1 also proved remarkably durable, surviving a meteor shower. Still, it proved susceptible to sunlight, enough to push it back into Earth's atmosphere where it burned up on re-entry on May 24, 1968. NASA continued with Project Echo, launching Echo 2, a similar but larger satellite balloon, in January 1964. But ultimately NASA chose to use satellites that could actively transmit data, rather than passively reflect signals.
https://en.wikipedia.org/wiki/Project_Echo
https://www.aps.org/programs/outreach/history/historicsites/penziaswilson.cfm
Penzias and Wilson tested everything they could think of to rule out the source of the radiation racket. They knew it wasn’t radiation from the Milky Way or extraterrestrial radio sources. They pointed the antenna towards New York City to rule out "urban interference", and did analysis to dismiss possible military testing from their list.
At the same time, the two astronomers learned that Princeton University physicist Robert Dicke had predicted that if the Big Bang had occurred, there would be low level radiation found throughout the universe. Dicke was about to design an experiment to test this hypothesis when he was contacted by Penzias. Upon hearing of Penzias’ and Wilson’s discovery, Dicke turned to his laboratory colleagues and said "well boys, we’ve been scooped."
The horn antenna was designated a National Historic Landmark in 1990. Its significance in fostering a new appreciation for the field of cosmology and a better understanding of our origins can be summed up by the following: "Scientists have labeled the discovery [of the CMB] the greatest scientific discovery of the 20th century."