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SPICES: spectro-polarimetric imaging and characterization of exoplanetary systems.
(Experimental Astronomy, 2012-10)
SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and ...
Exoplanet Albedo Spectra and Colors as a Function of Planet Phase, Separation, and Metallicity
(The Astrophysical Journal, 2010-11-20)
First generation space-based optical coronagraphic telescopes will obtain images of cool gas- and ice-giant exoplanets around nearby stars. Exoplanets lying at planet-star separations larger than about 1 AU—where an exoplanet ...
Radiometer Calibration Using Colocated GPS Radio Occultation Measurements
(Institute of Electrical and Electronics Engineers, 2014-10)
We present a new high-fidelity method of calibrating a cross-track scanning microwave radiometer using Global Positioning System (GPS) radio occultation (GPSRO) measurements. The radiometer and GPSRO receiver periodically ...
Interpolation Method for Update with Out-of-Sequence Measurements: The Augmented Fixed-Lag Smoother
(American Institute of Aeronautics and Astronautics, 2016-11)
In this study, the authors propose a novel method to handle OOSMs in Kalman filtering. The proposed method, called the augmented fixed-lag smoother (AFLS), is based on the fixed-lag smoother (FLS) formulation, which has ...
Trapped photoelectrons during spacecraft charging in sunlight
(Institute of Electrical and Electronics Engineers, 2015-09)
For a dielectric spacecraft charging in sunlight, the potentials are different on the sunlit and dark sides. Differential charging of spacecraft surfaces can trap low-energy electrons by means of potential wells and barriers. ...
Laser-Guide-Star Satellite for Ground-Based Adaptive Optics Imaging of Geosynchronous Satellites
(Journal of Spacecraft & Rockets, 2017-05)
In this study, the feasibility and utility of using a maneuverable nanosatellite laser guide star from a geostationary equatorial orbit have been assessed to enable ground-based, adaptive optics imaging of geosynchronous ...
Atmospheric characterization of cold exoplanets using a 1.5-m coronagraphic space telescope
(EDP Sciences S.A., 2012-05)
High-contrast imaging is currently the only available technique for the study of the thermodynamical and compositional properties of exoplanets in long-period orbits, comparable to the range from Venus to Jupiter. The ...
Telemetry Fault-Detection Algorithms: Applications for Spacecraft Monitoring and Space Environment Sensing
(2018-05-19)
Algorithms have been developed that identify unusual behavior in satellite health telemetry. Telemetry from solid-state power amplifiers and amplifier thermistors from 32 geostationary Earth orbit communications satellites ...
Response of geostationary communications satellite solid-state power amplifiers to high-energy electron fluence.
(American Geophysical Union, 2015-05)
The key components in communications satellite payloads are the high-power amplifiers that amplify the received signal so that it can be accurately transmitted to the intended end user. In this study, we examine 26 amplifier ...
Assessment of Radiometer Calibration With GPS Radio Occultation for the MiRaTA CubeSat Mission
(Institute of Electrical and Electronics Engineers, 2016-12)
The microwave radiometer technology acceleration (MiRaTA) is a 3U CubeSat mission sponsored by the NASA Earth Science Technology Office. The science payload on MiRaTA consists of a triband microwave radiometer and global ...