Otto Berg's flight spare of a cosmic dust detector experiment built for the Mariner spacecraft, identical to the unit actually carried to Mars during the 1960s. The device features an 8.75″ circular mirrored acoustical cosmic dust sensor attached to a box labeled "Cosmic Dust Electronics," with serial ports on front and back. In very good condition, with a few cracks to the surface of the mirror. According to Berg's notes, this unit is totally identical to the one carried to Mars and used while in orbit to detect the numbers and nature of cosmic dust in that atmosphere. He notes that he was one of three co-experimenters involved in the development of the device.
The cosmic dust detector carried on Mariner 4 famously registered 17 hits in a 15-minute span on September 15, 1967, part of an apparent micrometeoroid shower which temporarily changed the spacecraft's attitude and probably slightly damaged the thermal shield. On December 10 and 11, a total of 83 micrometeoroid hits were recorded, causing perturbation of the attitude and degradation of the signal strength. On December 21, 1967, communications with Mariner 4 were terminated.
From the collection of Dr. Otto Berg.
