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700 matches in All Departments
Full color reprint of NASA History Office Study of 2007.
Illustrated throughout.
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Earth as Art (Hardcover)
National Aeronautics & Space Admin
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R1,869
R968
Discovery Miles 9 680
Save R901 (48%)
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Ships in 12 - 17 working days
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Provides striking full color images from earth-observing
environmental satellites in orbit srount the planet. This book
shows patterns, shapes, colors, and textures of the land and
atmosphere.
Full color publication. NP-2009-066-GSFC. This colorful book
provides concise explanations and descriptions-easily read and
readily understood-of what is now known of the chain of events and
processes that connect the Sun to the Earth, with special emphasis
on space weather and sun-climate.
With illustrations and photographsp in full color.
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The Book of Mars (Hardcover)
Samuel Glasstone; Created by United States National Aeronautics and
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R917
Discovery Miles 9 170
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Ships in 12 - 17 working days
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A vital, often predominant function in every space mission is that
of communications. From the moment of launch, the only connection
between spacecraft and earth is the communications system. This
system is responsible for sending scientific data back to earth in
the specified quality and quantity together with engineering data
reporting the condition of the spacecraft. The communications
system also provides the capability of tracking the spacecraft and
commanding it to take certain actions. Without an effective
communications system a successful mission would not be possible.
To appreciate the challenge that one faces in designing such
systems for planetary exploration, one must consider the enormous
distances that are involved. Voyager spacecraft, for example, are
now more than one billion miles from earth, tens of thousands of
times farther than the most distant communications satellite, and
continue to transmit data and respond to commands. The necessity of
minimizing spacecraft weight presents a major problem to
communications systems designers. The far-reaching implications of
spacecraft weight become apparent as the designer considers the
problems of providing power supply, antennas, and other necessary
devices and supporting elements. Another important challenge is the
extreme reliability required of the communications system on the
spacecraft. Once the spacecraft is launched, on-board failures can
no longer be repaired except by use of redundant systems. System
degradation due to aging, imperfect antenna pointing, or imperfect
trajectories can be expected; and the designer must know how much
degradation to expect from each case and must design the equipment,
the operations, and the procedures of data analysis accordingly.
The telecommunications engineer works with the most precise and
advanced techniques of the engineering world. Since the launch in
1958 of Explorer I, the first free-world satellite, there has been
substantial progress in improving communications capability. Even
though substantial progress has been made in the last 25 years,
space exploration is still in its infancy. There has been no
exploration beyond the solar system. There are numerous galaxies
and billions of stars to investigate. Bigger and tougher challenges
are still ahead; more exciting times are yet to come. These
challenges will undoubtedly call for more advanced
telecommunications systems to transmit information to and from deep
space. Telecommunications technology is still in its infancy.
Through the years, a number of telecommunications design
techniques, procedures, and analyses contributing to the success of
deep space exploration missions have been developed and applied.
The purpose of this book is to provide descriptive and analytical
information useful for the optimum design, specification, and
performance evaluation of deep space telecommunications systems.
The book emphasizes system performance information. Long, tedious
derivations are not included. The book should serve to acquaint new
telecommunications engineers with the techniques available to them
and should summarize for the experienced engineers the analyses and
information necessary for their work. It also provides a background
for understanding the interface between the Deep Space Network and
the spacecraft and is intended to facilitate the conceptual designs
and analyses for the enhancement of telecommunications performance
and assurance of compatibility between spacecraft and ground system
capabilities.
Gemini was the intermediate manned space flight program between
America's first steps into space with Mercury and the amazing and
unprecedented accomplishments achieved during the manned lunar
expeditions of Apollo. Because of its position between these two
other efforts, Gemini is probably less remembered. Still, it more
than had its place in man's progress into this new frontier. Gemini
accomplishments were manyfold. They included many firsts: first
astronaut-controlled maneuvering in space; first rendezvous in
space of one spacecraft with another; first docking of one
spacecraft with a propulsive stage and use of that stage to
transfer man to high altitude; first traverse of man into the
Earth's radiation belts; first extended manned flights of a week or
more in duration; first extended stays of man outside his
spacecraft; first controlled reentry and precision landing; and
many more. These achievements were significant in ways one cannot
truly evaluate even today, but two things stand out: (1) it was the
time when America caught up and surpassed the Soviet Union in
manned space flight, and (2) these demonstrations of capability
were an absolute prerequisite to the phenomenal Apollo
accomplishments then yet to come. Project Gemini is now little
remembered, having vanished into that special limbo reserved for
the successful intermediate steps in a fast-moving technological
advance. Conceived and approved in 1961, the second major project
in the American manned space flight program carried men into orbit
in 1965 and 1966. Gemini thus kept Americans in space between the
path-breaking but limited Earth-orbital missions of Project Mercury
and the far more ambitious Project Apollo, which climaxed in 1969
when two men first set foot on the Moon. This book is a detailed
history of the failures and victories of the Gemini program.
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Nadine Gordimer
Paperback
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R398
R330
Discovery Miles 3 300
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