Abstract
The U.S. National Space Science Data Center (NSSDC) provides several services which are of use to astronomers. The most important of these is the Astronomical Data Center (ADC) which currently contains about 700 astronomical catalogs, primarily from ground-based observations. Most of these are available electronically at no cost to anyone with a connection to 1nternet or Decnet. They can also be obtained in other forms at the cost of preparation and distribution. The NSSDC also contains most data from U.S. scientific satellites and many from other countries. Through its NASA On-line Data Information Services (NODIS), it also provides a directory of other data sets and services for both space and, for astronomy, ground-based data. The NSSDC distributes a number of CDROMs including one with 114 of the most requested astronomical catalogs. Others contain planetary images and Halley Watch observations. Other services are available through NODIS or by referral from NODIS. The ADC is also cooperating with the American Astronomical Society (AAS) to provide on-line access to AAS information and abstracts from astronomical publications.
