Holmdel in Monmouth County, New Jersey — The American Northeast (Mid-Atlantic)
Karl Jansky Radio Astronomy Monument
This sculpture commemorates Jansky's discovery, first announced in 1933, which gave birth to the science of radio astronomy. The sculpture is oriented as Jansky's antenna was at 7:10 p.m. on September 16, 1932, at a moment of maximum signal. As his directional antenna rotated, the center of our galaxy came into view in the direction of the constellation Sagittarius, low on the southern horizon.
Radio Astronomy pioneer Karl Jansky died in 1950, years before the scientific community realized the significance of his discovery. In 1973, the International Astronomical Union gave his name to the international unit of radio flux density. Jansky's work led to a number of breakthroughs in astronomy: the discovery of quasars, pulsars, radio galaxies, and, near this site in 1964, the Nobel Prize-winning discovery by Bell Laboratories scientists of the cosmic microwave
background which has revolutionized our understanding of the origin of the universe.
Erected by Bell Laboratories.
Topics. This historical marker and monument is listed in these topic lists: Exploration • Notable Events • Notable Places • Science & Medicine. A significant historical date for this entry is September 16, 1932.
Location. 40° 21.9′ N, 74° 9.8′ W. Marker is in Holmdel, New Jersey, in Monmouth County. The marker and sculpture are located far behind the giant transistor shaped water tower behind what was once a reflection pond on the abandoned Bell Labs facility. Touch for map. Marker is at or near this postal address: 101 Crawfords Corner Road, Holmdel NJ 07733, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within 4 miles of this marker, measured as the crow flies. Radio Astronomy (approx. half a mile away); Geraldine Morgan Thompson (1872-1967) (approx. 2.6 miles away); British Retreat Route (approx. 3.3 miles away); Middletown Village (approx. 3.3 miles away); a different marker also named Middletown Village (approx. 3.7 miles away); North American Phalanx (approx. 3.7 miles away); a different marker also named British Retreat Route (approx. 3.8 miles away); Fairview Cemetery Veterans Monument (approx. 3.9 miles away).
More about this monument. The picture on the marker is of, "Karl Jansky and his 100-foot-long rotating directional antenna, from a photograph taken in 1932."
Two other markers commemorating famous events or discoveries on Bell Lab sites have dissapeared. This marker was erected by a private company that no longer exists and is not being maintained. It will likely no longer exist in a few years.
Additional commentary.
1.
As of July,
2016, the former Bell Labs building has been reopened for office space, retail, and hotel rooms. The new company running the property has restored the Radio Astronomy Monument and is taking good care of it.
— Submitted December 14, 2016, by R. C. of Shrewsbury, New Jersey.

Photographed By R. C.
7. Radio Astronomy plaque near roadway
This is the only sign to alert visitors of the existence of the historic site within the former Bell Laboratories compound. "Near this site in 1932, Bell Labs scientist Karl Jansky first discovered radio waves coming from outer space, thus beginning the science of radio astronomy."
Credits. This page was last revised on March 15, 2017. It was originally submitted on March 23, 2009, by R. C. of Shrewsbury, New Jersey. This page has been viewed 3,597 times since then and 140 times this year. Photos: 1. submitted on March 23, 2009, by R. C. of Shrewsbury, New Jersey. 2. submitted on December 14, 2016, by R. C. of Shrewsbury, New Jersey. 3. submitted on March 23, 2009, by R. C. of Shrewsbury, New Jersey. 4. submitted on December 14, 2016, by R. C. of Shrewsbury, New Jersey. 5, 6. submitted on March 23, 2009, by R. C. of Shrewsbury, New Jersey. 7, 8. submitted on March 24, 2009, by R. C. of Shrewsbury, New Jersey. 9. submitted on December 14, 2016, by R. C. of Shrewsbury, New Jersey. • Kevin W. was the editor who published this page.