The ultimate goal of the satellite laser ranging is the millimeter precision and accuracy. To achieve this goal, all the individual contributors to the ranging error budget must be well below millimeter level. The best existing ground based ranging systems are capable to achieve millimeter ranging precision when ranging to short distance terrestrial targets. However, ranging to Earth orbiting s...

satellite thermal control ensures safe operating temperature ranges for satellite components throughout the mission life. effects of altitude, spin, and position of satellite radiator(s) on the thermal control of a small low earth orbit (leo) satellite have been studied. results show that change in satellite altitude, in the range considered here, does not produce critical thermal conditions. h...

soil salinity has been a large problem in arid and semi arid regions. preparation of such maps is useful for natural resource managers. old methods of preparing such maps require a lot of time and cost. multi-spectral remotely sensed dates due to the broad vision and repeating of these imageries is suitable for provide saline soil maps. this investigation is conducted to provide saline soil map...

Arbuscular mycorrhizal fungi (AMF) are a group of obligate plant symbionts which can promote plant nutrition. AMF communities are diverse, but the factors which control their assembly in space and time remain unclear. In this study, the contributions of geographical distance, environmental heterogeneity and time in shaping AMF communities associated with Miscanthus giganteus (a perennial grass ...

the gravity recovery and climate experiment (grace), twin satellites launched in march 2002, are making detailed measurements of the earth's gravity field. it will yield discoveries about gravity and the earth's natural systems. different sensors and instruments have been placed in the grace satellites to fulfill the primary scientific objective of the mission in mapping the earth’s g...

Satellite formation flights are considered in the past few years as an effective alternative to large expensive satellites. The dynamics of relative satellite motion flying in the formation is complex and requires detailed study. This paper presents the approach based on the THEONA semi-analytical satellite theory and developed for orbits with arbitrary values of the eccentricity. The intermedi...

The New Horizons project is currently in progress, but until recently years ago, a mission to Neptune-Triton System predicted in the mid term 2008–2013 was one of the priorities of NASA’s Solar System Exploration theme. Any way, it is important to increase our knowledge on the dynamics of the inner satellites of Neptune, since according to some authors, this was a key question in the mission to...

As a global influenza pandemic appears imminent with the spread of avian influenza, the California Department of Health Services (CDHS) and the California Distance Learning Health Network (CDLHN) presented a live 90-min satellite broadcast and subsequent 2-hr small group problem-solving tabletop exercise to practice interventions needed to minimize the consequences of a pandemic event. Public h...

Satellite altimetry provides a precise measure of the vertical distance of the satellite borne altimeter to the instantaneous sea surface. The accuracy of this distance depends on the calibration of the altimeter, the quality of the reflecting target and the proper estimate of path delay. The general design characteristics for absolute altimeter calibration imply a large number of measurements ...