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The above picture shows the 40-foot planetary spectrograph used with the 24-inch telescope facility. This device employs a 12" x 14" single grating with 600 lines per millimeter. In the 4th order spectrum, the resolution is around 1.2 angstroms/millimeter.

During the 1970's and 80's, spectroscoptic studies of the carbon dioxide context of the Venusian atmosphere were made in the near-infrared wavelengths. As time progressed, different detectors were used to study the methane and ammonia content of the Jovian planets. Eventually, an exhaustive study of the sodium emission from Jupiter's satellite, Io, was observed with an imaging photometer.

Results allowed astronomers to see a 2 dimensional profile of the sodium cloud, and Jupiter's influence upon its size and shape. Over an extended period of time, a 3 dimensional picture could be analyzed over the complete orbit of Io around Jupiter.

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In the late 1980's, the ACRIM II facility was in full operation at a site slightly lower, and to the east of the main Table Mountain facilities. In this aerial view, the solar tracker is seen outside of the 'butler' building.

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Above, J. Young is seen smiling after the first successful attempt at aluminizing the big 48-inch mirror of the new 48-inch telescope facility (completed a few years earlier). The 48-inch telescope came from Cloudcroft, New Mexico. It was a Department of Defense satellite tracking instrument, moth-balled after being taken out of service.

JPL acquired the instrument, along with the vacuum chamber (seen in the background) to aluminize the mirror. The mirror weighs 1063 pounds, and its removal, cleaning, placing in the chamber, and re-installing back in the telescope is a three-man operation taking 3-4 days. After receiving extensive training, and seeing the results of the finished job, you can understand the smile! This picture was taken in May, 1994, just before the mirror was re-installed into the telescope.

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This closer view looking SSW shows the 24-inch facility to the upper right center. The bread- box automated telescope, then the Schmidt camera dome upper left center. The original 16- inch facility left center, then the Pomona 40-inch telescope building to the extreme lower left. The LIDAR building is at the bottom left center, and the 48-inch facility to the lower right.

In the picture below, the 48-inch facility is seen as of October, 1998. In the past few years, air conditioning units have been added to both the 24 and 48-inch facilities. The telescopes operate with far better 'seeing' conditions now that the dome interiors are 'conditioned' to the expected night-time temperatures each day preceeding observations. These A.C. units can be seen to the lower right of this building.

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The JPL Table Mountain Facility continues to evolve. New projects are always in the works. Visit our Projects page to see what's happening at the site today.