Arno Allan Penzias

Arno Allan Penzias was a German-born American physicist who shared the 1978 Nobel Prize in Physics with Robert Wilson for discovering cosmic microwave background radiation.

Holmdel Horn Antenna: A horn-reflector radio telescope at Bell Laboratories in Holmdel, New Jersey, built for satellite communications. Penzias and Wilson used this antenna when they detected the persistent microwave signal.
Radio Astronomy: The study of celestial objects and phenomena through radio waves. Penzias’s antenna measurements applied radio astronomy to an unexpected background signal.
Project Echo: A NASA communications experiment that used passive satellites to reflect radio signals between ground stations. The Holmdel antenna was built to support satellite communication experiments associated with Echo.
Big Bang: The expansion of the universe from an early hot, dense state into the cosmos observed today. The background radiation supplied strong evidence for the hot early-universe model.
Cosmic Microwave Background: The faint microwave radiation filling the universe, released when the early universe became transparent to light. The unexplained signal measured by Penzias and Wilson was this radiation.
Radio Telescope: An instrument that detects and measures radio waves from astronomical sources. The horn antenna functioned as a sensitive radio telescope.
Bell Telephone Laboratories: The research organization of the Bell System, known for telecommunications research and scientific discoveries. Penzias conducted the antenna work as a Bell Laboratories scientist.
Steady-State Theory: A cosmological model in which the universe expands but maintains constant average density through continuous matter creation. The detected background strongly favored a hot beginning over this rival cosmology.
Robert Woodrow Wilson: An American radio astronomer who shared the 1978 Nobel Prize in Physics for discovering the cosmic microwave background. Wilson worked with Penzias on the measurements that established the signal’s cosmic origin.
Thermal Noise: Random electrical fluctuations produced by the thermal motion of charged particles in a system. The persistent hiss was measured as excess noise above expected instrumental contributions.

Linked from 10 pages