Lifetimes of Lunar Satellite Orbits
Lifetimes of Lunar Satellite Orbits

Author: National Aeronautics and Space Administration (NASA)

Publisher: Createspace Independent Publishing Platform

Published: 2018-07-05

Total Pages: 40

ISBN-13: 9781722338787

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The Space Exploration Initiative has generated a renewed interest in lunar mission planning. The lunar missions currently under study, unlike the Apollo missions, involve long stay times. Several lunar gravity models have been formulated, but mission planners do not have enough confidence in the proposed models to conduct detailed studies of missions with long stay times. In this report, a particular lunar gravitational model, the Ferrari 5 x 5 model, was chosen to determine the lifetimes for 100-km and 300-km perilune altitude, near-circular parking orbits. The need to analyze orbital lifetimes for a large number of initial orbital parameters was the motivation for the formulation of a simplified gravitational model from the original model. Using this model, orbital lifetimes were found to be heavily dependent on the initial conditions of the nearly circular orbits, particularly the initial inclination and argument of perilune. This selected model yielded lifetime predictions of less than 40 days for some orbits, and other orbits had lifetimes exceeding a year. Although inconsistencies and limitations are inherent in all existing lunar gravity models, primarily because of a lack of information about the far side of the moon, the methods presented in this analysis are suitable for incorporating the moon's nonspherical gravitational effects on the preliminary design level for future lunar mission planning. Meyer, Kurt W. and Buglia, James J. and Desai, Prasun N. Langley Research Center RTOP 506-49-11-01...

Interstellar Boundary Explorer (IBEX)
Interstellar Boundary Explorer (IBEX)

Author: David McComas

Publisher: Springer

Published: 2014-06-18

Total Pages: 0

ISBN-13: 9781489999245

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over to nominal operations and began making our groundbreaking science observations. Remarkably, the IBEX project was able to do all this work including developing an entirely new launch capability, building and ying a unique and highly specialized spacecraft and instrument suite, and maintaining full funding for our Education and Public Outreach and Phase E science activities, while still under-running our original cost cap (as modi ed by NASA-directed changes), by roughly three-quarters of a million dollars. This book comprises a set of papers that describe the IBEX science, instruments, and mission and put these in the context of the existing knowledge of the interstellar interaction at the time of the launch. The book sets the stage for research that will be based on data from the IBEX mission. We sincerely hope that future researchers, authors and students will use this information to help in their studies. Chapter 1 [McComas et al. ] provides an overview of the entire IBEX program including the IBEX science, hardware, and mission. Chapter 2 describes the IBEX spacecraft and ight system [Scherrer et al. ]. Chapters 3–4 provide the details of the IBEX-Hi instrument [Funsten et al. ] and background monitor that is built into it [Allegrini et al. ], while Chapters 5–7 describe the IBEX-Lo instrument [Fuselier et al. ], how IBEX-Lo can measure the interstellar neutrals directly entering the heliosphere [Möbius et al.

Orbital Debris
Orbital Debris

Author: National Research Council

Publisher: National Academies Press

Published: 1995-07-07

Total Pages: 225

ISBN-13: 0309051258

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Since the beginning of space flight, the collision hazard in Earth orbit has increased as the number of artificial objects orbiting the Earth has grown. Spacecraft performing communications, navigation, scientific, and other missions now share Earth orbit with spent rocket bodies, nonfunctional spacecraft, fragments from spacecraft breakups, and other debris created as a byproduct of space operations. Orbital Debris examines the methods we can use to characterize orbital debris, estimates the magnitude of the debris population, and assesses the hazard that this population poses to spacecraft. Potential methods to protect spacecraft are explored. The report also takes a close look at the projected future growth in the debris population and evaluates approaches to reducing that growth. Orbital Debris offers clear recommendations for targeted research on the debris population, for methods to improve the protection of spacecraft, on methods to reduce the creation of debris in the future, and much more.

Satellite Orbits
Satellite Orbits

Author: Oliver Montenbruck

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 378

ISBN-13: 3642583512

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This modern presentation guides readers through the theory and practice of satellite orbit prediction and determination. Starting from the basic principles of orbital mechanics, it covers elaborate force models as well as precise methods of satellite tracking. The accompanying CD-ROM includes source code in C++ and relevant data files for applications. The result is a powerful and unique spaceflight dynamics library, which allows users to easily create software extensions. An extensive collection of frequently updated Internet resources is provided through WWW hyperlinks.

Lunar Reconnaissance Orbiter Mission
Lunar Reconnaissance Orbiter Mission

Author: R.R. Vondrak

Publisher: Springer

Published: 2014-11-22

Total Pages: 0

ISBN-13: 9781489992604

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The Lunar Reconnaissance Orbiter (LRO) was successfully launched on June 18, 2009 and joined an international eet of satellites (Japan’s SELENE/Kaguya, China’s Chang’E, and India’s Chandrayaan-1) that have recently orbited the Moon for scienti c exploration p- poses. LRO is the rst step to ful ll the US national space goal to return humans to the Moon’s surface, which is a primary objective of NASA’s Exploration Systems Mission - rectorate (ESMD). TheinitialLROmissionphasehasaone-yeardurationfullyfundedunder ESMD support. LRO is expected to have an extended phase of operations for at least two additional years to undertake further lunar science measurements that are directly linked to objectives outlined in the National Academy of Science’s report on the Scienti c Context for Exploration of the Moon (SCEM). All data from LRO will be deposited in the Planetary Data System (PDS) archive so as to be usable for both exploration and science by the widest possible community. A NASA Announcement of Opportunity (AO) solicited proposals for LRO instruments with associated exploration measurement investigations. A rigorous evaluation process - volving scienti c peer review, in combination with technical, cost and management risk assessments, recommended six instruments for LRO development and deployment. The competitively selected instruments are: Cosmic Ray Telescope for the Effects of Rad- tion (CRaTER), Diviner Lunar Radiometer Experiment (DLRE), Lyman-Alpha Mapping Project (LAMP), Lunar Exploration Neutron Detector (LEND), Lunar Orbiter Laser - timeter (LOLA), and Lunar Reconnaissance Orbiter Camera (LROC).