Engineering topics
Publications and source records attributed to Nilsen, E..
In August 2000, an independent assessment of the Europa Orbiter baseline mission was performed to evaluate the planned implementation. As part of this activity, multiple alternative mission concepts were investigated that could meet the full science objectives as well as concepts that could meet a reduced set of science objectives.
Since their initial discovery in 1992, to date only a relatively small number of Kuiper Belt Objects (KBO's) have been discovered. Current detection techniques rely on frame-to-frame comparisons of images collected by optical telescopes such as Hubble, to detect KBO's as they move against the background stellar field. Another technique involving studies of KBO's through occultation of known stars has been proposed. Such techniques are serendipitous, not systematic, and may lead to an inadequate understanding of the size, range, and distribution of KBO's. In this paper, a future Kuiper Belt Mapping Radar is proposed as a solution to the problem of mapping the size distribution, extent, and range of KBO's. This approach can also be used to recover radar albedo and object rotation rates. Additional information is contained in the original extended abstract.
Odyssey is an exciting comet nucleus orbiter mission submitted to the Discovery 2000 Annoucement of Opportunity.
There is a general realization within NASA that -onboard autonomy- is needed. Exact specifications of what that means are often vague at the onset of the mission design process.
An Europa Lander mission has been assigned high priority for the post-2005 time frame in NASA's Space Science Enterprise Strategic Plan.
This paper describes the results of a study to update the concepts for the exploration of Neptune to reflect the latest projections for spacecraft technology developments within the next several years.
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In cooperation with NASA's Solar System Exploration Subcommittee (SSES) the Jet Propulsion Laboratory (JPL) is conducting a series of studies to assess the feasibility of planetary science missions proposed for launch in the 2006-2010 time frame and to prioritize technology development steps that will enable these missions.
Venus sample return missions have been studied occasionally for the last forty years, but only recently has technology advanced to the point where this kind of mission has been realistic.
Within th Solar System, Venus presents a set of unique challenges to obtaining samples and returning them to Earth.
A mission to return a sample to Earth from the surface of Venus faces a multitude of challenges.
This paper examines the processes involved in performing these advanced concepts studies, and analyzes the application of heuristics in the development of an advanced in-situ planetary mission.
The Galileo spacecraft will explore the atmosphere, magnetosphere, and major satellites of Jupiter.
The Galileo Jupiter orbital mission using the Low Gain Antenna (LGA) requires a higher degree of spacecraft state knowledge than was originally anticipated. Key elements of the revised design include onboard buffering of science and engineering data and extensive processing of data prior to downlink. In order to prevent loss of data resulting from overflow of the buffers and to allow efficient use of the spacecraft resources, ground based models of the spacecraft processes will be implemented. These models will be integral tools in the development of satellite encounter sequences and the cruise/playback sequences where recorded data is retrieved.