<title>On-orbit science in a small package: managing the ALEXIS satellite and experiments</title>

Abstract

The Array of Low Energy X-ray Imaging Sensors (ALEXIS) satellite is Los Alamos' first attempt at building and flying a small, low cost, rapid development, technology demonstration and scientific space mission. The ALEXIS satellite contains the two experiments: the ALEXIS telescope array, (which consists of six EUV/ultrasoft x-ray telescopes utilizing multilayer mirrors, each with a 33 degree field-of-view), and VHF ionospheric experiment called BLACKBEARD. The spacecraft is controlled exclusively from a ground station located at Los Alamos. The 113-kg ALEXIS satellite was launched by a Pegasus booster into a 750 X 850 km, 70 degree inclination orbit on April 25, 1993. Due to damage sustained at the time of launch, ground controllers did not make contact with the satellite until late June. By late July, full satellite operations had been restored through the implementation of new procedures for attitude control. Science operations with the two onboard experiments began at that time. This paper will discuss our experience gained in launching and managing this small scientific and technology demonstration satellite.