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Granite Oil Slip Table
Photograph number P-2784Ac

In 1963, spacecraft vibration tests were conducted in the Environmental Laboratory at JPL.  A slab of granite, coated in oil, provided a smooth and stable base for the magnesium slip plate, test fixture, and Ranger 6 spacecraft mounted on it.  There were vibration exciters (shakers) on each end, capable of more than 25,000 pounds of force.  The horizontal fixture at left was used for low frequency vibration testing, and the equipment was capable of testing along all three spacecraft axes.

During the 1960s, Ranger, Surveyor, and Mariner spacecraft were developed, built, and tested at JPL.  Because of the heavy use, a similar but smaller test fixture was used for vibration tests on spacecraft components and assemblies.  Building 144 still contains test facilities, but this equipment was removed and the room now contains an acoustic chamber.

Other photos of this test equipment, with and without spacecraft attached, can be seen in an online photo album. (JPL internal only.  Log in with JPL username and password, and scroll down to P-1853 and P-1891).  For more information about the history of JPL, contact the JPL Archives for assistance.  [Archival and other sources: TR32-353, TR32-241, 1963 telephone book, 1964 map, floor plans.]

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Viking Stereo Viewer
Photograph number 324-1954

This interactive computer-based stereo viewing system was used to analyze Mars topography images generated by the Viking 1975 lander cameras.  Two 17” video monitors faced a scanning stereoscope mounted between them on a table.   Left and right lander camera image data were sent to the left and right monitors.  Panning controls on the stereoscope helped align one image with the other to create a stereo image, 640×512 pixels in size.  A mouse was used for finely controlled rotation of the monitors.  An article about the system described a prototype mouse, used before this photo was taken in 1976.  “The track ball is a baseball-sized sphere protruding from the top of a retaining box and capable of being rotated freely and indefinitely about its center….”

The resulting images could be displayed on additional monitors and were used to create contour maps and other images that aided lander surface operations.  The system was developed by Stanford University and JPL.

For more information about the history of JPL, contact the JPL Archives for assistance. [Source:  Viking 1975 Mars Lander Interactive Computerized Video Stereophotogrammetry, JGR, Vol. 82, No. 28.]

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1944 Map of JPL
HC 3-1294

On October 31, JPL celebrated its 76^th anniversary.  It began with a few individuals working on the Caltech campus and testing rocket motors in the Arroyo Seco.  By the time this 1944 map of “The Project” was created, JPL was supported by Army Air Corps contracts and the site included more than 50 offices, labs, and test facilities.

The JPL Archives has a collection of maps available online, including a 1940 sketch made by Frank Malina and maps once found in JPL hard copy telephone books.  If you would like to learn more about the early JPL site and buildings, search the JPL Archives online catalog for the word “facilities” and find reports from JPL to the Army and NASA that include photos and descriptions of each building.  (The maps and most online documents are JPL internal only.  Log in with your JPL user name and password.)

For more information about the history of JPL, contact the JPL Archives for assistance. [Archival and other sources: History Collection documents  3-1294 and 3-29; and the Archives map collection.]

Photograph 328-161Ac
Is it a JPL magic trick?

In 1960-61, several different experiments were conducted at JPL, in the search for a frictionless bearing for use in space applications, gyroscopes and other machinery.   There were cryogenic, gas, and electrostatic types of bearings, and the photo above shows a magnetic bearing.  It was suspended by counterbalancing the force of gravity and an electromagnet.  A servo feedback system continually corrected the current flow through the electromagnet to keep it stable.

For more information about the history of JPL, contact the JPL Archives for assistance. [Archival and other sources: Lab-Oratory November 1961 and Publications of the Jet Propulsion Laboratory.]