The Green Bank site, circa 1980, in an aerial shot from the north. The telescopes are, from left to right, the 85-foot Howard E. Tatel, the 40-foot, the 85-3 and 85-2 elements of the Green Bank Interferometer, and 300-foot, and the 140-foot (43-meter) in its downward aiming maintenance position. A fourth member of the GBI, the 42-foot, would have been 13 miles away on a hilltop.
Calibration Horn Antenna
The Calibration Horn Antenna, nicknamed the “Little Big Horn,” at Green Bank in 1961. As its name implies, this 120-foot long horn antenna was used to measure the intensity of radio waves coming from the sky’s strongest non-solar radio source, Cassiopeia A. The Calibration Horn measured a total power output for Cas A at a frequency of 1.4 GHz (a wavelength of 20cm), and thus provided astronomers with a standard reference point on the sky against which they could measure other sources.
Future Home of a Giant
This was the building site for the 300-foot telescope at Green Bank. The mound at far right contains the corn stalks from the field, fenced to keep animals out.
Not an Ice Cream Truck
The RFI van, affectionately known as the Ice Cream Truck, with its enormous antenna raised to collect radio frequency interference in the surrounding countryside. Photo taken in October 1981.
No Spark Plugs in Zone 1
The electric spark in a spark plug generates a more powerful burst of radio waves than that which our telescopes receive from objects in space. Vehicles using spark plugs are strictly forbidden inside the telescope zone, called Zone 1, in Green Bank.
Diesel vehicles, like this old VW Rabbit, don’t use spark plugs. We maintain a fleet of diesel vehicles for use inside Zone 1.
Before the Internet
Anyone who observed in Green Bank from the mid-1960s through the 1980s was familiar with the shuttle. Every morning, 365 days a year for many years, vehicles left both Green Bank and Charlottesville and met in the parking area off U.S. Rt. 250 at the top of Shenandoah Mountain in the George Washington National Forest. The drivers traded the vehicles with their passengers/cargo and then returned to their office of origin. People (both visitors and NRAO staff), equipment, data tapes, interoffice mail – all traveled between Green Bank and Charlottesville on the shuttle. In this November 1977 photo, long-time drivers Merle Kerr (Green Bank) and James Garland (Charlottesville) and their vehicles are at the exchange point on Shenandoah Mountain.