Engineering topics
Asmar, S.
Publications and source records attributed to Asmar, S..
The Mars Express/NASA Project at JPL
ESA s Mars Express Mission involves international collaboration between the European Space Agency (ESA) and the European space agencies with the National Aeronautics and Space Administration (NASA) as a junior partner. The primary objective of this mission is to search for hydrologic resources on the surface of Mars. Mars Express was launched from Baikonur, Kazakhstan on June 2, 2003 and arrived at Mars on December 25, 2003. Orbital science observations started in January 2004.
Ultra-stable oscillators for radio science investigations on planetary entry probes
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Reducing cost with autonomous operations of the Deep Space Network radio science receiver
This paper describes the Radio Science Receiver system and the savings it has brought to mission operations. The design and implementation of remote and autonomous operations will be discussed along with the process of including user feedback along the way and lessons learned and procedures avoided.
First deep space operational experience with simultaneous X- and Ka-bands coherent tracking
This paper describes the new DSN science capability and highlights of the engineering work that lead to its development. It will also discuss experience with operations along with statistics and data quality.
Decadal study for radio science investigations in the Deep Space Network
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Instrumentation of large radio telescopes for radio science investigations
This paper presents an overview of the DSN instrumentation as well as examples of data showing the achieved accuracies.
MGS Radio Science Team Meeting: Mission Status
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Cassini Radio Science Data Management & Team Website
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Improving on the High Latitude Topography of the Moon Via Precise Timing of the Lunar Prospector Radio Occultations
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The Lunar Crustal Thickness from Analysis of the Lunar Prospector Gravity and Clementine Topography Datasets
The Lunar Prospector spacecraft has mapped the gravity field of the Moon to a level of resolution never achieved before, and a spherical harmonic representation to degree and order 100 is available. When combined with the topography dataset produced by the Clementine mission, the resulting Bouguer anomaly map is interpreted to model the thickness of the lunar crust. Such models are crucial to understanding the lunar thermal history and the formation of geological features such as mascon basins, several more of which have been newly discovered from this dataset. A two-layer planetary model was used to compute the variations of the depth to the lunar Moho. The thickness values ranged from near 0 to 120 km. There is significant agreement with previous work using the Clementine gravitational field data with differences in specific locations such as South Pole-Aitken Basin, for example.
A spacecraft going behind the Sun will support SOHO
The problems that can be solved by combining the Solar and Heliospheric Observatory (SOHO) and the magnetic structures on and around the sun (MagSonas) observations are discussed. A magneto-Doppler imager and X and Ka band linearly polarized radio signals sent to the other side of the sun can support extended SOHO mission. This is the purpose of the MagSonas mission. The MagSonas radio system, designed to serve as spacecraft communications and a sounding coronal magnetic field, is described.
A Spacecraft Going Behind the Sun can Support SOHO
Solar variations, including active regions, flares, coronal mass ejections and solar wind, originates in magnetic fields.
Mars Microrover Telecom Subsystem
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Trends in Performance and Characteristics of Ultra-Stable Oscillators for Deep Space Radio Science Experiments
This paper surveys the trends in stability and spectral purity performance, design characteristics including size and mass, as well as cost and history of these clocks in space.
Search for Gravitational Wave Trains with the Spacecraft ULYSSES
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