ACTS provided real-time links to investigate the use of satellites for remote astronomy in two separate experiments. In the first user trial, T1-VSATs were installed at the Apache Point Observatory in southern New Mexico and on the campus of New Mexico State University (NMSU) in Albuquerque, New Mexico [76]. ACTS provided a 1.79 Mbps link to the observatory. The observatory s sensors produced a primarily digital output (e.g. _; a charged coupled device s image of objects in the sky), allowing the digital transmission of the observatory s data products in realtime. During an observation session, the telescope user remained at his home institution and did not have to be physically present at the telescope facility.

This link also allowed operation and control of the telescope facility by remote users, using the same interfaces as on-site observers. The ACTS trials allowed NMSU to test the capability of the remote interface, and give the user a touch and feel for access and control. In this aspect, the real-time nature of the link was critical to the safety of the 11.5-foot telescope as it was moved under remote control. A wide band (1.544 Mbps) channel was also required to handle the data generated by the telescope s array of sensors. In addition, the ACTS trials included the testing and evaluation of additional communication links to support the non-real-time data network used to support observatory management, data base sharing, computer and video conferencing, and other collaborative services for the science...