An Aerobee-Hi rocket carrying a Harvard-built ultraviolet spectrometer was launched from White Sands, N.M., earlier this month. It was the second rocket-test for the spectrometer, which is scheduled to be launched in a satellite sometime in December.
The Harvard instrument, which has been in preparation under Leo Goldberg, Higgins Professor of Astronomy, since early 1959, is designed to observe the sun in the short ultraviolet wavelengths that cannot penetrate the earth's atmosphere.
If the spectrometer is successfully launched this December above the atmosphere in a satellite, the Orbiting Solar Observatory II, it will send back to earth a picture of the sun that astronomers have never seen before.
Previous Trial Failed
Last spring a duplicate of the spectrometer was launched at the White Sands Proving Grounds, but the device failed to operate properly and crashed on the desert when its parachute failed.
During the latest test the Aerobee-Hi rocket rose to an altitude of over 200 kilometers. At this height the spectroscope, mounted in the nose of the rocket, was automatically pointed at the center of the sun and observed the ultraviolet radiation above the layers of air that normally form that part of the solar spectrum.
For roughly three minutes at the peak of the rocket's orbit, the spectrometer functioned in its first mode of operation, recording the intensity of ultraviolet light over a narrow range of frequencies. Three and one half scans were completed before the Aerobee plunged back towards earth.
A Few Buge
William Liller, Robert Wheeler Wilson Professor of Applied Astronomy, one of the project directors, noted that while "there are a few bugs to be ironed out" the Harvard instrument will be ready for OSO II by the winter.
The spectrometer's second mode-of operation was not tested during the Sept. 6 flight. In this mode the 40 lb. gold-plated box that holds the electronic equipment will scan up-and-down and across the solar disc in order to pick up an entire image of the sun at these short wave-lengths. Scientists expect that these ultraviolet "pictures" of the sun will help them better understand chromospheric solar flares.