Flight-spare x-ray spectrometer identical to one that flew on the OSO-V satellite launched on 22 January 1969. It was used to examine the very high temperature spectrum from solar flares in the x-ray region. Developed at NASA's Goddard Space Flight Center this experiment provided the first detailed observations of x-ray and ultraviolet radiation from solar flares estimated to be at temperatures of 10 to 30 million degrees. This flight-spare instrument is similar to one flown on OSO-III. Transferred from GSFC/NASA in 1983, it was on display in the "Stars" Gallery from 1983 until October 1997.
This object is on display in Boeing Aviation Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.