News Release Archive:

News Release 846 of 1051

April 30, 1996 12:00 AM (EDT)

News Release Number: STScI-1996-20

The Original National Geographic Society - Palomar Observatory Sky Survey to be Available on 8 CD-ROMs

The full news release story:

The Original National Geographic Society - Palomar Observatory Sky Survey to be Available on 8 CD-ROMsView this image

The Space Telescope Science Institute (STScI) and the Astronomical Society of the Pacific (ASP) are pleased to announce the availability of RealSky CD, the digitized Palomar Observatory Sky Survey compressed by a factor of 100x, available on 8 CD-ROMs.

For the first time, amateur astronomers, educators, and the public will have access to the actual sky survey plates used for more than thirty years by research astronomers. The unprecedented level of telescopic detail, especially of extended images like galaxies, clusters, and nebulae, is not available in any other astronomical software package.

The images are digitizations of the E plates from the first NGS-POSS, conducted with the Oschin Telescope (48" Schmidt) on Palomar Mountain during the 1950s. The NGS-POSS was funded by a grant from the National Geographic Society to the California Institute of Technology.

With funding from NASA, the more than 750 plate images were first digitized during an intensive eight-year effort by STScI astronomers to prepare the Guide Star Catalog which provides the coordinates of target stars that are used by the Hubble Space Telescope for acquiring and locking onto celestial targets.

RealSky CD is a more compressed version of the original Digitized Sky Survey (DSS) which was made available on 102 CD-ROMs two years ago. The DSS was compressed by a factor of 10 and offered images that were nearly indistinguishable from the original data. The 100x compression factor of RealSky is not suitable for professional research activity but provides an invaluable tool for the educational and amateur communities.

RealSky CD offers single-color (one passband) images of the entire northern sky, down to -15! declination—the approximate location of Sirius—and angular resolution of 1.7 seconds, revealing stars as faint as 19th magnitude.

The included RealSkyView software allows users to view and manipulate the images under Windows (3.1, '95, NT) or Macintosh operating systems. UNIX and VMS software is also included with both versions. Both RealSky CD and the original 10x Digitized Sky Survey can be accessed directly from TheSky (v.4) astronomy software by simply clicking on the desired sky area and specifying the image size. CDS are packaged with instruction manual and accompanying software.

RealSky CD will be available July 1, 1996. The cost of the 8 CD-ROM set will be $225.00 if ordered prior to the release date. After July 1, the price will be $250.00. Within the U.S., add $16 for shipping and handling charges; Canada and Mexico residents please add $20; all other countries add $50 for delivery by airmail. California residents please add applicable sales tax. Use your Visa or Mastercard to order at 1-800-335-2624 or send orders by check, credit card, or institutional purchase orders to:

The Astronomical Society of the Pacific RealSky CD Orders 390 Ashton Avenue San Francisco, USA tel: 415/337-1100 fax: 415/337-5205 e-mail:


Ray Villard
Space Telescope Science Institute, Baltimore, MD
(Phone: 410-338-4514)

Wendy Eck
Astronomical Society of the Pacific, San Francisco, CA
(Phone: 415-337-1100)