bluuebunny/crossref_metadata_2025_split huggingface dataset:
Weather Satellites
Authors: Singer S. Fred , Rao P. Krishna 
Published: October 2003

AbstractThe world's first meteorological satellite, a polar‐orbiting satellite, was launched from Cape Canaveral on 1 April 1960. Named TIROS for Television Infrared Observation Satellite, it demonstrated the advantage of mapping Earth's cloud cover from satellite altitudes. TIROS showed clouds banded and clustered in unexpected ways. Sightings from the surface had not prepared meteorologists for the interpretation of the cloud patterns that the view from an orbiting satellite would show.The spacecraft, the sensors, the communication links, the data, and the data uses of weather satellites today bear little resemblance to what they were at the time of that pioneering effort. In the decades that have elapsed, satellite weight has grown from about 100 kg to nearly a metric ton; vidicon cameras have given way to scanning radiometers; hand‐drawn analyses of the data have been replaced by computer‐generated products; what was analog has become digital; and capabilities have expanded to include atmospheric profiling, ocean sensing, and collecting and relaying environmental data recorded by remote reporting platforms. In addition, weather satellites now measure the space environment in which they operate. Just as their technology and uses have evolved, so have weather satellites proliferated internationally. Meteorological spacecraft in polar orbit and geostationary orbits are operated by the United States, the European Space Agency, Japan, India, Russia, and the People's Republic of China.This article gives the history of the development of weather satellites from 1960 to the present. International cooperation in monitoring Earth and its environment is discussed.Satellites by their nature rely on remote sensing. Fundamental topics include: reflection and scattering of solar radiation, thermal emission for the surface and the atmosphere, active probing using radar and lidar. Other topics include applications, climate studies, and the continuity and future of operational satellite programs.
Muscle Loss in Space: Physiological Consequences
Authors: Baldwin Kenneth M. , Reggie Edgerton V. , Roy Roland R. 
Published: October 2003

AbstractRecent findings clearly suggest that one of the hallmarks of exposing humans and animals to the environment of spaceflight involves the process of muscle atrophy and associated deficits in one's performance capability. This article describes the effects of spaceflight and/or states of muscle unloading on (1) the intrinsic structural and functional properties of skeletal muscle, (2) the performance of muscular activities associated with locomotion and other motor tasks both during and after exposure to spaceflight, and (3) theoretical concepts for enhancing our current understanding of the effectiveness of countermeasures routinely used either to maintain or prevent observed muscle loss and corresponding deficits in musculoskeletal function. Data from both human and animal models from in‐flight and ground‐based experiments are examined.
First Flight of Man in Space
Authors: Klimuk Petr I. , Vorobyov G.I. 
Published: October 2003

Abstract
The twentieth century was one of rampant technological development, of unprecedented flourishing of science, a century in which grandiose, fantastic ideas became reality, and when the dreams of many generations of people who lived and now live on Earth came true.
There were a great many ideas, discoveries, projects, and accomplishments in the century just past. But among all the numerous outstanding human achievements in the twentieth century that captured the contemporary imagination, the most thrilling were the launch of the first artificial satellite and, especially, the flight of the planet's first cosmonaut, Yuriy Alekseyevich Gagarin on the Vostok spacecraft.
The launch of the first artificial satellite into orbit around Earth took place on 4 October 1957 at 22:28 Moscow time marking the start of the Space Era in human history. Yuriy Gagarin's spaceflight, launched on 12 April 1961 at 09:07 Moscow time, lasted for 108 minutes, during which the spacecraft carrying the first cosmonaut completed a full orbit around Earth and then landed safely in the scheduled recovery area. This flight marked the start of the Era of Human Presence in Space.
These two events are directly linked; without the first, the second could never have occurred. The first became a momentous milestone in the history of technological progress; the second was the embodiment of a centuries‐old dream of humankind.
This article details the preparations for the first flight and how Yu. A. Gagarin was chosen for the mission, Biographical information on Gagarin is given.
Exploration of Mars by theUSSR
Authors: Zakharov Alexander V. , Moroz V.I. 
Published: October 2003

AbstractMars research began long before the Space Age. Ground‐based astronomical observations using photometry polarimetry, and infrared spectrometry were performed in the Soviet Union throughout the 1950s and 1960s. G.A. Tikhov attempted to find evidence of life on Mars using spectroscopic techniques. Theoretical models for the internal structure of the planet began to be developed.Early Soviet planetary spacecraft were developed by Special Design Bureau 1. One of the primary motivations for the development of long‐term Martian research programs was a desire to find life on the planet. It was generally understood that this project had to begin elsewhere—learning more about the planet Mars itself. Nevertheless, early Soviet spacecraft carried a spectrophotometer for observations of the so‐called Sinton bands, which were, at that time, presumed to indicate the presence of organic material on Mars.Eight attempts were made to launch a spacecraft to Mars, starting in 1962. Only the fourth spacecraft, the Mars‐1 (1962) executed a flyby, but communications were lost prior to the flyby. Jet Propulsion Laboratory made two attempts (1964) during this period, one of which was successful: Mariner‐4 performed a Mars flyby and transmitted an image of the planet.In 1965, S.P. Korolev transferred all unmanned interplanetary space flight projects to another facility, the Design Bureau and Plant named after S.A. Lavochkin.This article gives details on the Mars 2–7 spacecraft. The phobos spacecraft was launched to study phobos and not Mars.
Spacelab
Authors: Hoffmann Hans E.W. 
Published: October 2003

Abstract
Spacelab is the European contribution to the Post Apollo Program. Spacelab is a reusable, multipurpose, modular laboratory and in the first 10 years of Space Shuttle operation, became its major payload. This payload remained attached to the Orbiter during the whole flight and maintained certain dependences. Spacelab was not a habitat, so that the Mission and Payload Specialists stayed in the Orbiter during take‐off and landing and used it also as living quarters.
Spacelab was designed for a 10‐year lifetime and/or 50 missions. Inside the laboratory, called the module, a shirtsleeve atmosphere for the astronauts was required; experiments on the outside had to be conducted in the open space on a pallet. Both module and pallet were accommodated inside the Shuttle payload bay and remained attached to the Shuttle during the mission. This fact limited the time of a Spacelab mission to the time of a Shuttle flight.
This article gives details on the various components of the Spacelab (module, pallet instrument painting, environmental control, command systems, electrical power systems).
On 4 June 1974, the contract to design and build Spacelab was given by the European Space Agency (ESA) to an industrial consortium of companies from eight European countries.
For most of the time from 1974 to 1983, the Spacelab development ran parallel to the Shuttle development on a no exchange of funds basis to use common hardware and subsystems as much as possible.
The flight hardware, schedule and cost are described. Missions are listed and the lessons learned from this cooperative program are presented.
Communication Satellite Development in Russia
Authors: Kozlov A.G. , Bartenev V.A. 
Published: October 2003

Abstract
Work on the practical applications of artificial Earth satellites began in Russia (USSR) in 1961. The first of these satellites, the small low‐altitude Strela series spacecraft of the “electronic mail” type, were developed by the Scientific Production Association for Applied Mechanics (NPO PM) and placed in orbit in 1964. One year later, the Experimental Design Bureau‐1 (OKB‐1), (currently S.P Korolev Energia Rocket and Space Corporation) inserted the active relay satellite Molniya‐1 into a highly elliptical orbit. In 1965, work on this spacecraft was transferred to NPO PM and, for the next 30 years, this organization was the only one in the country developing telecommunication satellites. The first geostationary satellite was inserted into orbit in 1975.
It was not until 1997 that a communication satellite, Kupon, developed by another organization, the S.A. Lavochkin NPO, was placed in orbit, and in 1999, the communication satellite Yamal developed by Energia was launched. At present, work to design communication satellites is being conducted by the Machine Building NPO and the M.V. Khrunichev State Space Scientific Production Center.

The spacecraft that were and are being developed in Russia may be divided into three categories on the basis of the types of orbit:

satellites in low circular orbits, primarily at an altitude of 1500 km (such satellites are used to form multisatellite communications systems);

Molniya
type satellites in highly elliptical orbit;

satellites in geostationary orbit.

These three categories are discussed in detail in this article.
International Space Station
Authors: Michael Hawes W. 
Published: October 2003

AbstractThe establishment of a long‐term, low Earth orbiting outpost has long been a goal of space exploration advocates. A variety of orbiting space stations, envisioned by writers, engineers, and scientists for years, have been developed, launched, and deorbited. The Soviet Union and Russia have flown several Salyut stations and only recently terminated operations of the Mir Space Station. The United State flew three missions on the Skylab Space Station that was launched in 1975.The long developmental history of the International Space Station (ISS) includes many lessons and are discussed. The huge scale of the project offers many engineering, policy, and management lessons for our future endeavors in space. Despite the many challenges and the long development period, the project is now demonstrating great success an overview of the configuration of the ISSW given. The segments contributed by the U.S., Russia, Canada, Europe, and Japan are detailed. These partners have formulated a share agreement to allocate all of the critical ISS resources. In November 2000, the first permanent crew docked with and entered the International Space Station. Since then, the International team has continued to outfit and augment the ISS. At this time, the fifth expedition crew is well into their stay on board the ISS. The results of many years of painstaking work are evident as the ISS flies overhead.
Plasma Thrusters
Authors: Morozov Alexey I. , Balebanov Vyacheslav M. 
Published: October 2003

AbstractPlasma thrusters are a class of electric propulsion in which the working medium has the form of plasma in the acceleration zone. The presence of plasma, both positive ions and negatively charged electrons, in the acceleration gap distinguishes plasma thrusters from ion thrusters where the acceleration gaps contain only positively charged ions. In ion propulsion, the space charge field restricts the emissions of ions from the emitter (ion generator), and thus ion thrusters have a relatively low thrust density and require a high acceleration voltage. As a result, they can be efficient only with an acceleration voltage >1 kV and exhaust velocities of ≥30 km/s.Because the acceleration gaps in a plasma thruster contain both positive ions and electrons, no space charge is needed. For this reason, there are no limitations in theory on the thrust density in plasma thrusters, and the exhaust velocity may range from a few km/s to hundreds or more km/s. Of course, different plasma thruster designs are optimal for each range of exhaust velocities and power levels.Plasma thrusters, like other electric propulsion thrusters, are of interest for space technology primarily because of their capacity to reach high exhaust velocities, greater than those attained by thermochemical (liquid or solid) fuel rocket engines. In a number of instances, other features of such thrusters may also be of interest.The chemical energy contained in the working medium is not sufficient to attain high velocities. For this reason, plasma thrusters, like other rocket engines, require special sources of energy. Today, these sources may be either the Sun or nuclear processes of one kind or another (fission, radioactive decay). For each specific flight, optimal velocity parameters exist, defined with respect to minimum total mass of propellant and power source. The optimal exhaust velocities for the majority of purposes are currently within the range of approximately 15–30 km/s.These thrusters are classified primarily on the basis of the mechanism for accelerating the plasma. Three basic types of plasma thrusters are identified: Thermal plasma thrusters; electromagnetic (Ampere's force) plasma thrusters; and the third class encompasses plasma thrusters in which acceleration is achieved through both kinetic gas pressure and Ampere's force.The division of plasma thrusters into three groups on the basis of the acceleration mechanism is very general. However, detailed classification of all possible plasma thrusters on the basis of their physical or design features is virtually impossible, This article describes only representatives of the three types of plasma thrusters that have already functioned in space.
Skylab
Authors: Kerwin Joseph 
Published: October 2003

Abstract
A space station has been an obvious part of space exploration since people began to think seriously about space travel. Skylab was a program that was being designed and trained for simultaneously, and the design and training were taking place in parallel with the Gemini, and later, the Apollo manned flights. Thus, the problems and experiences of those flights shaped the Skylab design.
As spacecraft and boosters for Project Apollo, NASA's lunar landing program, were defined, space station concepts derived their specifics from them. Modifications of the Command Module, the Lunar Module, and various configurations of the Apollo booster series, were studied. NASA wanted to use its hardware for programs beyond Apollo. In 1965, the concept of Apollo Extension Systems was formalized at NASA Headquarters and very soon became the Apollo Applications Program (AAP). The concept later named Skylab was just one of the missions proposed by AAP.
This article details the development of Skylab and discusses the first, second, and third missions. Skylab's goals were to discover whether humans could live safely in weightlessness and uncover any problems with design. Also it was necessary to determine whether productive science experiments could be accomplished. Results of the medical findings, human factors and design, and productivity are given for the three missions. Skylab returned to Earth in 1979 and was a lesson in planning how to dispose of space assets.
Global Navigation Satellite System
Authors: Menshikov V.A. , Solovyev G.M. 
Published: October 2003

Abstract
The Global Navigation Satellite System (Glonass) was designed to provide global real‐time determination of the position and velocity of an unlimited number of moving objects at any point on the Earth's surface, in the air, and in space. This system was developed in response to an order from the USSR (Russian Federation) Ministry of Defense. By instruction of the Russian Federation's President, the Glonass system was put into operation on 24 September, 1993. A 7 March, 1995 decree of the RF Government put the system at the disposal of the world community in standard mode intended for civil, commercial, and scientific use without a user fee.
A RF Presidential decree of 18 February, 1999 designated the Glonass as a dual‐purpose (military and civilian) space navigation system.
The system makes it possible to obtain highly accurate navigation location information with a maximum error less than or equal to 50–70 meters for position and 15 cm per second for velocity from any point on the globe or in near‐Earth space. Information is received in real time after a two to three minute pause, when the user's navigational system has just been turned on and continuously thereafter. At the same time, the system provides the capability to link the user's timescale with the State unified timescale with an error of no more than one microsecond. If the user's equipment can implement special methods for processing navigational information or differential operating modes are used, the accuracy with which the user's position is determined may be improved significantly. Tests have shown that the maximum error in such cases does not exceed a few meters.
This article gives details on the concepts involved in positioning the system and the design of the satellite. Launch takes place at the Baykonur Spaceport. The Ground Control Complex tracks the satellite. The use of differential methods for navigation provides reliability and these methods are discussed. Because positioning is achieved through uninterrogated measurements of pseudorange and pseudovelocity, the number of users of the Glonass space navigational system is unlimited and may be as large as possible. Uses in space, air, ground, and the sea are detailed.
Global Positioning System (
GPS
)
Authors: Parkinson Bradford , Spilker James , Elkaim Gabriel 
Published: October 2003

Abstract
The Global Positioning System, commonly referred to as GPS, is a worldwide, satellite‐based positioning and timing system that allows suitably equipped radio receivers to locate themselves in four dimensions, latitude, longitude, altitude, and time, anywhere there is a reasonably clear view of the sky. The system is also known as NAVSTAR, a convenient nickname that is not an acronym. The GPS system was developed, deployed, and is currently operated by the U.S. Air Force. GPS enables precision weapon delivery for all branches of the U.S. Department of Defense, as well as allied nations. Additionally, GPS supports civilian positioning and was always intended to support civil operations. The complete satellite constellation and ground support equipment that make up GPS was declared “operational” in December 1994, although civil use of the developmental signals started in the early 1980s.

The fundamental operation is as follows: the 24 GPS satellites are uploaded from the ground with their current and predicted positions (called ephemeris or orbital parameters). Small corrections of their space‐borne atomic clocks are also uploaded. This information is broadcast to the user as a data modulation on an L‐band signal (1575 MHz for most civilian users) that doubles as a precise, one‐way ranging signal. Ranging is achieved by synchronizing the start time of a pseudorandom sequence of bits transmitted from the GPS satellites at an accuracy of about one nanosecond (10
−9
s). Three very important results are achieved by this implementation. First, this makes GPS ranging a one‐way signal that allows an infinite number of users to receive the signal and compute their position without saturating the GPS system. Additionally, this makes the GPS receiver passive, so that it does not radiate radio‐frequency (RF) energy. Last, by receiving four or more satellite signals, users can synchronize their local clocks to GPS time, obviating the need for a very high quality and very expensive atomic clock in the receivers.

The design objectives of the GPS system were to provide a continuously available, worldwide, all‐weather, three‐dimensional precision navigation system for both military and civilian users on land, at sea, or in the air (or even in space). Selected application of the GPS system are discussed. Many topics presented are on the cating edge of research.
Chandra X‐ray Observatory
Authors: Weisskopf Martin C. 
Published: October 2003

Abstract
The Chandra X‐ray Observatory (originally called the Advanced X‐ray Astrophysics Facility—AXAF) is the X‐ray component of NASA's “Great Observatory” Program. Chandra is a NASA facility that provides scientific data to the international astronomical community in response to scientific proposals for using it. The Observatory is the product of the efforts of many organizations in the United States and Europe. The Great Observatories also include the Hubble Space Telescope for space‐based observations of astronomical objects primarily in the visible portion of the electromagnetic spectrum, the now defunct Compton Gamma‐Ray Observatory that was designed to observe gamma‐ray emission from astronomical objects, and the soon‐to‐be‐launched Space Infrared Telescope Facility (SIRTF). The Chandra X‐ray Observatory (hereafter CXO) is sensitive to X rays in the energy range from below 0.1 to above 10.0 keV, corresponding to wavelengths from 12 to 0.12 nanometers. The relationships among the various parts of the electromagnetic spectrum, sorted by characteristic temperature and the corresponding wavelength are illustrated in this article.
X‐ray astronomy is an extremely important field because it has been found that all categories of astronomical objects (or a subset thereof), from comets to quasars, emit X‐rays. Thus learning how and why these objects produce X‐rays are fundamental to our understanding of the way astronomical systems work. This, together with the large amounts of energy required to produce X‐rays, makes their study interesting and exciting. A second reason that the field is so important is that the vast bulk of the matter in the Universe that we can directly observe through the electromagnetic radiation that it emits is in the very hot (temperatures of millions of degrees) X‐ray emitting gas that fills the space between galaxies in clusters of galaxies, the largest collections of matter in the Universe. The CXO is the prime method of gaining new information about the X‐ray emission seen in the Universe.
The CXO was named in honor of the late Indian‐American Nobel laureate, Subrahmanyan Chandrasekhar, nicknamed “Chandra” which means “moon” or “luminous” in Sanskrit. He was one of the foremost astrophysicists of the twentieth century and, in 1983, was awarded the Nobel prize for his studies of the physical processes important to the structure and evolution of stars.
The observatory and its instrumentation are discussed. Scientific results are detailed CXO's role in solving the mystery of gamma ray bursts is also discussed.