[PDF] Three Dimensional Lunar Trajectories eBook

Author : A. B. Mickelwait
Publisher :
Page : 65 pages
File Size : 48,68 MB
Release : 1958
Category :
ISBN :

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The purpose of this paper is to present theoretical calculations of lunar trajectories from the point of view of the guidance problem. Section 1 contains the conventional two-dimensional analysis with the usual decomposition of the actual N-body problem, the earth, moon, vehicle, sun, etc., into the more tractable succession of two-body pro blems. The analytic statement of the required accuracy to impact on the moon's surface is then determined and compared with the actual accuracy needed. Section 2 examines the effect on the necessary guidance accuracy of launching out of the plane of the moon. This three-dimensional analysis indicates that the velocity accuracy requirements increase sharply as the plane of the trajectory is inclined with respect to the plane of the moon, and also that the accuracy requirements vary greatly for different launch times, both for given times of the day and given days of the month. Methods for analytically determining appropriate launch times and azimuths are also given. Section 3 is a brief application of the ideas presented above to some of the special problems posed by attempting to establish a lunar satellite.

Author : Richard J. Weber
Publisher :
Page : 1 pages
File Size : 39,47 MB
Release : 1961
Category :
ISBN :

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A CATALOG OF COAST PATHS ETWEEN THE Earth and the Moon is presented, accounting for three-dimensional factors but neglecting multib dy effects. Flight times, velocity increments, and launch azimuths are given for various positions of the Moon and various injection points in the northern hemisphere. The distance c vered during powered flight is found to have an important effect on the mission energy requirements. The effect of flight-path angle at burnout is studied; nonhorizontal burnout is often advantageous. The effect of launching from an Earth orbit, rather than directly from the surface, is discussed. Because precession may cause an unfavorable orientation of the orbital plane, departure from a permanent space station is usually undesirable. T e velocity ired landing location. (Author).

Author : Jeffrey S. Parker
Publisher : John Wiley & Sons
Page : 452 pages
File Size : 50,36 MB
Release : 2014-06-25
Category : Technology & Engineering
ISBN : 1118855310

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Based on years of research conducted at the NASA Jet Propulsion Laboratory, Low-Energy Lunar Trajectory Design provides high-level information to mission managers and detailed information to mission designers about low-energy transfers between Earth and the moon. The book answers high-level questions about the availability and performance of such transfers in any given month and year. Low-energy lunar transfers are compared with various other types of transfers, and placed within the context of historical missions. Using this book, designers may reconstruct any transfer described therein, as well as design similar transfers with particular design parameters. An Appendix, “Locating the Lagrange Points,” and a useful list of terms and constants completes this technical reference. Surveys thousands of possible trajectories that may be used to transfer spacecraft between Earth and the moon, including transfers to lunar libration orbits, low lunar orbits, and the lunar surface Provides information about the methods, models, and tools used to design low-energy lunar transfers Includes discussion about the variations of these transfers from one month to the next, and the important operational aspects of implementing a low-energy lunar transfer Additional discussions address navigation, station-keeping, and spacecraft systems issues