We report 1.87 lm photometry and astrometry of the inner satellites (Proteus, Larissa, Galatea, and Despina) and ring arcs of Neptune, obtained with the Hubble Space Telescope and its near-infrared camera NICMOS. From comparison with the Voyager data obtained at visible wavelengths, the small bodies orbiting within the ring region of Neptune have a near-infrared albedo consistently low, but hig...

The propagation time of a signal, emitted by moving along an elliptical orbit satellite from the GPS (or GLONASS) confi gurations is very important ingredient theory, based on formalism null cone and accounting for effects General Relativity Theory. For case satellites, orbiting plane elliptic orbit, it has been proved that signal between satellites given combination integrals first, second thi...

Abstract Space radiation particles will cause a variety of effects on orbiting satellites, such as single event effects, total ionizing dose, displacement damage, etc. In response to these space BeiDou Navigation satellites M15/M16 operating in medium earth orbit (MEO) developed the first integrated monitor for high-energy proton and particle based detection technology. This payload realizes jo...

Space Resource America Corporation is engaged in developing new concepts for communications satellite systems that will avoid interference with any of the Geostationary satellites and can provide a significant increase in global capacity compared with that of the GEO ring. Additionally, since all satellites in such a system are flying in formation, they will not interfere with each other. The c...

Abstract The FY-3 satellites are China's second generation polar-orbiting meteorological satellites. high-energy particle detector (HEPD) suite of measures protons and electrons in different energy ranges. As the fifth satellite series, FY-3E continues to observe electrons. Here, we use Monte Carlo simulations based on GEANT4 code model electron calibrate electron/proton campaigns at Space Elec...

NOAA (National Oceanic and Atmospheric Administration) LEO environmental satellites provide continuous coverage of Earth, supplying high-resolution global meteorological, oceanic and space observation data. In addition, these satellites are part of the international COSPAS – SARSAT program, which aides search and rescue teams worldwide. The USA segment, referred to as SARSAT (Search and Rescue ...

This paper presents a model predictive control approach for regulating the attitude of magnetically actuated satellites. Unlike other contributions in this area, a predictive control approach is developed which guarantees closed-loop stability of satellite configurations with unstable open-loop pitch dynamics. With the pitch axis being unstable, two magnetic dipoles are used exclusively for reg...