LITERATURA AUXILIAR

http://history.nasa.gov/SP-4110/vol2.pdf

Chertok, Boris Rockets and People py5aal v3.pdf - 7399 KB Visualizar

We still had enough propellant for all sorts of experiments on Baykal,

but Kerimov and Mishin, inspired by the congratulations from the Central

Committee and Council of Ministers, insisted that we finish up our production

in space and bring the spacecraft back to Earth by any means. On 2 November,

after somehow setting up the spacecraft using the ionic system, the commands

were issued to start up the descent cycle programs. The ionic system slipped

up somewhere in the Brazilian Magnetic Anomaly, and the braking burn sent

the spacecraft toward Earth on a long, flat trajectory that emerged beyond

the limits of the authorized corridor. The APO system destroyed 7K-OK

vehicle No. 5. This time our tracking system and the anti-ballistic missile

system closely monitored the descent module’s descent trajectory. The vehicle

was blown up after it passed over Irkutsk. Had there been no APO system,

it might have landed 400 kilometers east of Ulan-Ude. On 3 November, we

boarded our planes and flew from the Crimea to Moscow....

http://history.nasa.gov/SP-4110/vol3.pdf

COUTINHO INTROÇÃO ÀS PARTICULAS PRESAS AMAS 1805 KB Visualizar

https://sites.google.com/site/edselfreitascoutinho/

Langlois et Taberlet Le noyau terrestre PY5AAL.pdf - 1042 KB Visualizar

http://baudolino.free.fr/Noyau/index.html

Li & Temeri The Electron Radiation Belt n PY5AAL.pdf - 48 KB Visualizar

http://nova.stanford.edu/~vlf/IHY_Test/Tutorials/TheMagnetosphere/Papers/liTemerin.pdf

PINTO E OUTROS Novo Olhar Seguranca Sist Eletricos py5aal.pdf - 384 KB Visualizar

http://www.mantenimientomundial.com/sites/mmnew/bib/notas/olhar.pdf

Saboia Marques AMAS py5aal.pdf - 512 KB Visualizar

http://sites.google.com/site/angeloleitholdpy5aal/pesquisas/artigos/

Anomalia_Magnetica_Atlantico_Sul_Marques_Saboia.pdf

HEILMANN, RODRIGUES AVALIAÇ SIST DETEC DESC ATMOSF VLF ZEUS PY5AAL.pdf - 187 KB Visualizar

http://www.cbmet.com/cbm-files/14-c71f8500ab5fabae153af820c32dc94e.pdf

LAIBIDA JR., AlbaryTeoria Cinética Veicular .PY5AAL pdf - 477 KB Visualizar

BRUM, Christiano Garnett Marques; VARIABILIDADE DA ABSORÇÃO DE RUÍDO CÓSMICO VIA

RIÔMETRO E MODELAGEM NUMÉRICA DOS PROCESSOS ASSOCIADOS PY5AAL.pdf - 7932 KB Download

Para se obter uma descrição do campo geomagnético é preciso inclinar o eixo da Terra em aproximadamente 11°

e deslocá-lo em 500 km, a partir do centro geométrico terrestre, na direção 6,5°N e 162°E .

As linhas de campo magnético, quando comparadas à esfera terrestre, se aproximam mais

da superfície da Terra sobre a costa sudeste da América do Sul e sobre o

Oceano Atlântico, produzindo nesta região um mínimo absoluto na intensidade

do Campo Magnético Total. A região da AMAS é um grande

sorvedouro de elétrons. Tal fato foi observado há mais de 40 anos (Dessler,

1959) e, a partir de então, várias observações vêm sendo feitas através de

satélites, balões e técnicas de solo e inúmeros trabalhos teóricos têm sido

publicados, na tentativa de explicar o aumento do fluxo de partículas e os

efeitos aeronômicos decorrentes da mesma (Costa, 1991; Abdu et al., 1973;

Batista, 1975; Trivedi et al., 1973; Trivedi et al., 1975; Trivedi e da Costa, 1980;

Pinto e Gonzalez, 1988; Martin, 1972; Abdu et al., 1982)..

A região da AMAS é povoada por partículas energéticas que interagem

fortemente com os constituintes atmosféricos produzindo, nesta região, efeitos

ionosférico muito semelhantes àqueles observados nas regiões aurorais

(Gledhill e Van Rooyen, 1962; Doherty, 1971; Zimuda, 1966), tais como

precipitação de elétrons e partículas carregadas de origem solar, galáctica e de

partículas aprisionadas nos cinturões de radiação. Uma explicação para este

fato é que os elétrons aprisionados nas linhas de campo geomagnético, ao se

deslocarem sob a ação do efeito resultante da deriva, da curvatura e do

gradiente do campo magnético, atingem uma altitude mínima nesta região

(Benbrook et al., 1983).A principal fonte de injeção de

partículas desta região são os cinturões de radiação de Van Allen.

A injeção de elétrons por difusão radial pode atuar tanto sobre elétrons, com

valores de energia específicos, como para elétrons de todas as energias. Este

fato propicia a ocorrência de diferentes estruturas no espectro de elétrons

aprisionados. É importante observar que a injeção de elétrons na região da

AMAS é um processo contínuo, sendo intensificado em períodos

geomagneticamente ativos.

O principal processo de perda de elétrons para a atmosfera na região da AMAS

é a difusão em ângulo de arremesso (pitch angle). Tal difusão pode ser

causada por dois principais mecanismos: espalhamento Coulombiano dos

elétrons pelos constituintes atmosféricos (difusão colisional) e interações

ressonantes entre ondas e elétrons nas freqüências ciclotrônicas e de balanço

(difusão em ângulo de arremesso ressonante).

A difusão de ângulo de arremesso de elétrons é um processo aleatório e

contínuo. A intensificação deste processo na AMAS pode ser compreendida

com base no estudo do movimento dos elétrons aprisionados no campo

geomagnético. Assim, após percorrerem suas trajetórias ao redor da Terra e

chegarem à região da AMAS, os elétrons têm seus pontos de espelhamento

localizados em altitudes menores, intensificando sua interação com o meio

atmosférico desta região.

Apesar da grande variação da densidade atmosférica com a altura (variação

exponencial), um elétron pode demorar a interagir com os demais constituintes

atmosféricos, podendo permanecer aprisionado na sua trajetória adiabática

durante várias derivas, desde que não atinja a região crítica da AMAS, que está

situada em torno de 100km de altitude, conforme estabelecido por Berger e

Seltzer (1972), como uma fronteira entre as regiões de elétrons aprisionados e

de elétrons em precipitação. Isto é equivalente à definição de um ângulo de

arremesso equatorial crítico e que limita o cone de perdas de forma que um

elétron se precipita quando atinge tal ângulo. Ao entrar na atmosfera, o elétron

irá sofrer colisões com os constituintes atmosféricos locais, atuando em

escalas de tempo onde os seus invariantes adiabáticos serão violados. O

resultado destas colisões é a difusão gradual dos elétrons para dentro do cone

de perdas com uma conseqüente diminuição na altitude de espelhamento que

ocorre até o instante da sua precipitação.

A evolução do espectro de energia dos elétrons, desde o seu aprisionamento

pelo campo geomagnético até o instante de sua precipitação (menor ou igual à

aproximadamente 100 km de altura), pode ser qualitativamente resumida nas

seguintes considerações: (1) o espectro de energia dos elétrons evolui para

uma forma de equilíbrio tipicamente exponencial e decrescente; (2) dado que a

profundidade atmosférica em 100 km de altitude é aproximadamente 3.10-4

g/cm2, os elétrons com energia menor do que 10 kev não alcançam a altura de

100 km (Berger e Seltzer, 1964); (3) considerando-se a inclinação das linhas de

campo magnético na região da AMAS é possível, em primeira aproximação,

supor uma distribuição isotrópica em 100 km, na qual a distribuição angular

tende para uma forma de equilíbrio; (4) estruturas tais como os picos no

espectro de elétrons de alta energia (Berger e Seltzer, 1964), embora sofram

degradação, tendem a manter-se ao longo da difusão devido à menor perda de

energia dos elétrons de alta energia ; e (5) o fluxo de elétrons tende a diminuir

devido, principalmente, ao efeito de espelhamento e ao espalhamento de 180o,

os quais são dependentes da energia eletrônica.

Os pontos de espelhamento das partículas aprisionadas em uma camada L, na

região da AMAS, encontram-se muito baixos (<100km) (Williams e Kohl, 1965;

Roederer et al., 1967). A deriva de prótons para oeste produz uma

concentração maior destas partículas no lado leste da AMAS, de forma que o

fluxo precipitado é mais intenso à leste da AMAS e diminui rapidamente na

direção oeste. Como exemplo desta variação, o fluxo de prótons para L=2 no

hemisfério sul atinge um pico aproximadamente 35 vezes maior do que o fluxo

médio precipitado para o mesmo valor de L no hemisfério norte. A Figura 1.22

apresenta a variação do fluxo de prótons precipitado em função de L e da

longitude para os dois hemisférios (Torr et al., 1975).

Um fluxo de elétrons maior que 10 partículas.cm-2.s-1.sr-1 com uma energia

≥300keV é suficiente para produzir ionização diurna a uma altitude de 72 km

(Zimuda, 1966). Para o mesmo fluxo produzir ionização noturna em

aproximadamente 90km de altura, são necessários elétrons de menor energia

(Ee ≥40keV). Kikuchi e Evans (1982) afirmam que os elétrons de 300keV são

importantes fontes de ionização, tanto para os horários diurnos quanto para os

noturnos e estimou um fluxo mínimo de 40 elétrons.cm-2.s-1.sr-1 como sendo o

fluxo necessário para produzir desvios diurnos na propagação das ondas de

VLF, por exemplo. A Figura 1.25 ilustra a relação entre a variação da altura

ionosférica e o fluxo de prótons observado, através da altitude de reflexão das

ondas de VLF, para energias iguais ou maiores do que 20MeV (Kossey et al.,

1983).

Existem evidências experimentais que confirmam uma precipitação constante

de elétrons e prótons energéticos na região da AMAS (Gledhill, 1976; Abdu e

Batista, 1977). Quanto à precipitação de elétrons, esta afirmação é

inquestionável. Porém para os prótons, há evidências que descartam tal

possibilidade, pois o fluxo de prótons, tanto em períodos calmos como em

períodos perturbados, é desprezível (Pieper et al., 1965; Gough, 1975). Por

outro lado, existem casos em que a presença dos prótons no fluxo de

partículas precipitadas na AMAS é aceita e discutida (Freden e Paulikas, 1964;

Vernov et al., 1967; Torr et al., 1975).

http://mtc-m16.sid.inpe.br/col/sid.inpe.br/jeferson/2004/08.04.16.30/doc/publicacao.pdf

English et all apollo protection radiation py5aal.pdf - 5463 KB Visualizar

The problem of protection against the natural radiations of the Van Allen belts

was recognized before the advent of manned space flight. The simplified solution is to

remain under the belts (below an altitude of approximately 300 nautical miles) when in

earth orbit and to traverse the belts rapidly on the way to outer space. In reality, the

problem is somewhat more complex. The radiation belts vary in altitude over various

parts of the earth and are absent over the north and south magnetic poles. A particularly

significant portion of the Van Allen belts is a region known as the South Atlantic

anomaly (fig. 2). Over the South Atlantic region,the geomagnetic field draws particles

closer to the earth than in other regions of the globe. The orbit inclination of a spacecraft

determines the number of passes made per day through this region and, thus,

determines the radiation dose that will accompany these passes for a set altitude and

~ spacecraft shielding.A major camplication concerningradiation stability within

the belts (includingthe South Atlantic anomaly portion) is a

result of high-altitude nuclear detonations.

In 1962, the United States detonated a1. 5-megaton thermonuclear device (Project

Starfish) in a portion of the Van Allen belt region and caused the radiation levels

within the belts to rise significantly. By 1969, the high -energy electron component

of the injected radiation had decayed to only

one-twelfth of the 1962 intensity. small amount of time spent in earth orbit

and the rapid traverse of the radiation belts during Apollo missions have minimized

astronaut radiation dose from the remaining Starfish electrons. However, recur -

rence of high-altitude nuclear testing wouldThe have a significant impact on Apollo earth-orbit

operations, and this possibility has been factored into radiation-protection planning

for Apollo space missions. Sources of current intelligence information on nuclear-device

testing are available to the NASA,and these sources are ready

to assist in the real-time management of any contingencythat might be caused

by the high-altitude detonation of a nuclear device.

Particles within the Van Allen belts spiral around the earth magnetic lines offorce and,

therefore, display directionality. This directionality varies continuously in

angular relationship to the trajectory of the spacecraft. Therefore, dosimetry instru -

mentation in the Van Allen belts must use relatively omnidirectional radiation sensors

so that the radiation f l u will be measured accurately.

The Van Allen belt dosimeter (VABD) (fig. 3) was designed specifically

for Apollo dosimetry within these radiation belts and has proved satisfactory because

dose values derived from its greater than 180" radiation acceptance angle have correlated

well with doses indicated by postflight analyses of passive dosimeters worn by the crewmen.

The nuclear -particle -detectionsystem (NPDS) (fig. 4) was designed to have a

relatively narrow acceptance angle and was intended to measure the isotropic proton

and alpha particles derived from solarparticle events. Experience with the NPDS within the highly

directional radiation fields of the Van Allen belts has emphasized the difficulty

in determining true flux levels using a detector of narrow angle response,

There are two problems in determining flux levels. First, orientation of the spacecraft relative

to the direction of the impinging particles is not precisely known at all times.

inaccuracy would result from the high statistical error inherent with low counting rates

when the detector is pointed away from the direction of particle flux.Second, even if

orientation were precisely known,

A compromise in VABD design was required for Apollo flammability considerations,

and this compromise resulted in the use of aluminum as a replacement for

tissue -equivalent plastic in the ionization-chamber walls, Aluminum is a satisfactory

replacement for tissue -equivalent plastic only if electron secondary radiation (brems -

strahlung) is a small portion of the total radiation

dose (as in the Apollo Program).Chambers of tetrafluoroethylene plastic would be

preferable to aluminum if flammability remains a design factor for future missions,

A detailed discussion of radiation dosimetry considerations for post-Apollo missions is contained

in references 2 and 3. No major solar -particle events have

occurred during an Apollo mission (fig. 1). Although much effort has been expended in

the field of solar -event forecasting, individual eruptions from the solar surface are

impossible to forecast. The best that can be provided at this time is an estimate of

particle dose, given visual or radiofrequency (RF) confirmation that

an eruption has occurred. A system of solarmonitoring stations, the Solar Particle

Alert Network (SPAN), provides a NASAsponsored network of continuous data on

solar -flare activity. The various components of this network are described in the

appendix. Approximately 20 percent of the largest solar flares (importance 2 bright

or larger) will result in particle fluxes in the earth/moon region that can be related

in intensity to early RF or visual characteristics. A warning interval of from less

than one to several hours (typically, 2 to 4 hours) is obtained between the

RF/visual indication and the appearance of particles

in the earth/moon region. Because only approximately 20 percent of the flares result

in particle events, it is not necessary to change normal mission procedures on the

basis of RF or visual observations alone. Rather, radiation sensors on board solarorbit

and earth-orbit satellites, as well as on board the Apollo spacecraft itself, are

used to confirm the particle event. Only after the appearance of particles is confirmed

would action be taken to protect the crewmen. For a typical event, approximately

8 hours would be available from the time particles are confirmed to the time of peak

radiation dose. Details concerning effects of solar-particle events on various phases

http://history.nasa.gov/alsj/tnD7080RadProtect.pdf

Campbell et McCandless Introduction to Space Sciences spacecraft applications py5aal.pdf - 5701 KB Visualizar

presence of areas of radiation around the earth was discovered by Dr.

James Van Allen using instruments aboard the early U.S. V-2 test flights

and, later, Explorer series satellites. It was found that some of the charged

particles present in space were able to enter the magnetosphere and become

trapped within the geomagnetic field. The gainfloss mechanics of this phenomenon

is still not completely understood, but the levels, dispersion, and

behavior of the trapped particles have become well described.

Early representations of “belts” of radiation surrounding the earth are

better described by distributions of particles within the magnetosphere

which follow closely the geomagnetic lines of flux. Areas of different

concentrations exist due to the types of particles (protons and electrons)

and associated energy levels. More energetic particles are generally

trapped closer to the earth, and the major concentrations of particles occur

around the equator where the minimum value of magnetic field flux

occurs. Figure 4-1 1 shows this distribution of trapped particles around the

earth in terms of particle types and energy levels (1E2 indicates 1 x lo2

MeV or mega-electron volts of energy). In some regions, the level of radiation

due to these trapped particles is sufficient to be disruptive to spacecraft

operations and hazardous to humans.

Although caught in the earth’s magnetic field, these particles are far

from stationary. Motion of these energetic charged particles is a combination

of spiraling around the magnetic field lines while bouncing from pole

to pole along the lines. A slower drift around the equator also occurs.

When these particles interact with the ionosphere as they spiral in towards

the earth in the vicinity of the poles, they produce the auroral phenomena

known as the “northern lights” in the northern hemisphere. A more serious

effect of these motions is the contribution to atmospheric heating by

particle precipitation in the auroral zones and by the electric currents

flowing at high and low latitudes.

The off-set geometry of the geomagnetic field, produces an asymmetry in the radiation belts

whichresults in an area where the belts are closer to the earth’s surface. This area occurs

just off the coast of Brazil in the Atlantic Ocean and is known as the

South Atlantic Anomaly. Spacecraft passing over this area experience a significantly

increased radiation dosage sufficient to cause concern when operating in this region.

spacecraft systems as they turn on and off. Spacecraft also continuously

emit heat, especially toward the “cold” (absorptive) blackness of space.

For some applications, certain spacecraft parts may always point toward

the sun while others may always point toward space. Within certain

defined limits, the craft must be able to balance the temperatures of all its

components. Several spacecraft have been lost or impaired due to the

freezing of propellant lines or the heating of an electronic component to

the point of failure.

As we have seen, the space environment is full of charged materials,

trapped solar particles, and ionized atmospheric constituents as the major

examples. Also, as they travel through space, orbiting spacecraft cut

through magnetic field lines of flux which tends to make charges want to

move. Operation within such an electrically rich and magnetically dynamic

environment can result in a buildup of charges on the surfaces of the

spacecraft to the point at which a current flow or discharge from one component

to another may result in damage to the system.

Some of the higher-energy particles present in space can penetrate the

skin and components of a spacecraft. These may deposit an electrical

charge inside electrical components or may even change the physical

structure of materials. Sudden depositions of electrical charge in computer

logic circuits or memories can corrupt data or even disrupt operation of

the satellite if a “phantom command” is sensed from such an event.

Buildup of radiation damage to semi-conductor materials can cause computer

chips to degrade to the point where commands may no longer be

able to be processed. Satellite operators have to be especially vigilant for

signs of these effects during periods of high solar activity.

http://www.scribd.com/doc/24853450/Intro-to-Space-Sciences

Brun et Ritchie Astronautics Aeronautics astronauts 1975 py5aal.pdf - 7461 KB Visualizar

Scientists believed that light flashes observed by Skylab 4 crew members

during their 16 Nov. 1973 to 8 Feb. 1974 mission as they flew

through the South Atlantic Anomaly-a slight asym etry in the

usually low over Brazil-were a previously unsuspected form of

radiation, Science magazine reported. The radiation seemed to consist

of atomic nuclei heavier than hydrogen which, when stripped of

electrons, would carry multiple positive electric charges.

The astronauts had seen the flashes when the spacecraft cabin

was dark and they were preparing for sleep. Scientists suspected

that the flashes were stimulated within the retina of the eye by the

high-energy cosmic-ray particles. Normally earth was shielded from

cosmic rays by the magnetic field, but strong penetrating cosmic rays

could reach as far into the field as the Skylab orbit.

Because the magnetic-field shielding of the earth weakened toward

the geomagnetic poles, it was possible to predict variations in cosmicray

exposure as Skylab moved away from the poles. During two test

periods, light-flash observations of Astronaut William R. Pogue

showed a close correlation with exposure variations

http://history.nasa.gov/AAchronologies/1975.pdf

Emme Astronautics Aeronautics 1966 chronology py5aal.pdf - 13578 KB Visualizar

PEGASUS I, 11, and 111 meteoroid detection

satellites-launched Feb. 16, May 25, and July 30, 1965,

respectively-had provided full year of data which defined “more

precise1 than ever before” near-earth meteoroid environment, NASA

reportel Data-including cumulative count of 1,000 “hits” on target

plate thickness, identification and location of specific panel hit, attitude

of spacecraft with respect to earth and sun at impact time, and time of

penetration-confirmed “protective adequacy” of Apollo manned lunar

landing spacecraft against meteoroids ; provided designers of future

spacecraft with guidelines on probability of meteoroid penetrations ;

and improved mapping of South Atlantic anomaly by measuring

electron radiation density.

http://history.nasa.gov/AAchronologies/1966.pdf

rumerman Nasa Historical databook VII py5aal ch1.pdf - 652 KB Visualizar

NASA began operating as the nation’s civilian space agency

in 1958 after passage of the National Aeronautics and Space

Act. It succeeded the National Advisory Committee for

Aeronautics (NACA).

The new organization was charged with preserving the role of

the United States “as a leader in aeronautical and space science

and technology,” expanding our knowledge of Earth’s atmosphere

and space, and exploring flight both within and outside the

atmosphere.The decade from 1989 to 1998 was extremely productive,

as NASA added to its already considerable list of achievements.

The decade was marked by assembly of the first orbiting Space

Station components, launch of the first two Great Observatories,

and an outstanding record of safe and fruitful missions.

http://history.nasa.gov/SP-4012v7ch1.pdf

rumerman Nasa Historical databook VII py5aal ch2.pdf - 3864 KB Visualizar

The Atlas I was the first of a new family of launch

vehicles that could boost payloads into low-Earth

orbit, geosynchronous-Earth orbit, and on interplanetary

trajectories. The launch vehicle was very similar to

the Atlas G Centaur, and it included two boosters, a

sustainer, two vernier single-start engines, and a

Centaur upper stage. An interstage adapter separated

the Atlas stage from the Centaur. The vehicle had

two new payload fairings, incorporated significant

improvements in the guidance and control systems,

and replaced analog flight control components with

digital units interconnected with a digital data bus.

Figure 2–11 shows an Atlas I. Table 2–65 lists

Atlas I characteristics.The first Atlas I flight

took place on July 25, 1990, with the launch of

the Combined Release and Radiation Effects Satellite (CRRES),

a joint NASA-U.S. Air Force project. The final

Atlas I launch took place on April 25, 1997, with

the launch of GOES-10 into geosynchronous orbit.

Although launch parameters varied slightly depending

on launch date, launch time, and payload weight, T

able 2–66 presents a typical launch sequence for a

geosynchronous mission.

http://history.nasa.gov/SP-4012v7ch2.pdf

rumerman Nasa Historical databook VII py5aal ch4.pdf - 7866 KB Visualizar

The spacecraft structure consisted of a main body

and six solar panels. A combination of passive and

active methods provided spacecraft thermal control.

Multilayer thermal blankets and thermal radiators

were used for passive thermal control. Heaters with

thermostats controlled the temperature of the batteries

, the star tracker, and the SXT.The spacecraft

flew in a slightly elliptical low-Earth orbit.

During five to six of its orbits each day, Yohkoh

passed through the radiation belts of the

South Atlantic Anomaly where the BCS, HXT, and most

channels on the WBS (all of which used high voltages)

had to be turned off to avoid damage to the instruments

and satellite.Observations from the instruments were

stored in the Spacecraft Bubble Data Recorder (BDR).

Approximately 50 megabytes of data were accumulated

each day and stored in the 10-megabyte on-board tape

recorder. To optimize the recorder, the BDR could operate

at several bit-rates—high, medium, and low. Switching

between the bit-rates was controlled both automatically

and by on-board deferred commands. This switching was

necessary because the high bit rate held only 42 minutes

of data. Some overwriting of data was permitted.The

satellite operated in several spacecraft and subsystem

modes. The two modes of principal interest were the

Quiet Mode and Flare Mode. Switching between these

two particular modes was controlled by a flare flag

generated by the WBS. Yohkoh’s operating mode determined

which instruments could collect the data and how much

they could collect. Generally, more HXT data was taken

during the Flare Mode than during the Quiet Mode.

http://history.nasa.gov/SP-4012v7ch4.pdf

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Three months later on 31 January 1958, the Army came through. Explorer 1 was

launched into orbit atop a Jupiter C IRBM to become America’s first artificial

satellite. In addition to a 108 MHz transmitter (which operated for a remarkable

113 days), the 68-kilogram (31-pound) satellite had onboard an experiment

devised by Professor James A. Van Allen of the University of Iowa to detect

charged particles in Earth’s magnetic field. In time, telemetry downlinked

from the first four Explorer satellites led to the discovery of the Van Allen

Radiation Belts, hailed as the single most important discovery of the IGY.

http://history.nasa.gov/STDN_082508_508%2010-20-2008_part%201.pdf

Tsiao Story NASA Spaceflight Tracking Data Network py5aal part 2.pdf - 4888 KB Visualizar

Take the seismometer network emplaced by Apollo 12, 14, 15,

and 16. It enabled the location of impacts and moonquakes

to be determined very precisely. The network of three

Lunar Surface Magnetometers enabled the study of solar

wind plasma movement by tracing its magnetic field.

Closing out the program, Apollo 17 carried an enhanced

package of surface experiments. With nuclear power from

the RTGs, ALSEP transmissions were received by NASA’s

Spaceflight Tracking and Data Network for years after

the last astronauts had left the Moon.

http://history.nasa.gov/STDN_082508_508%2010-20-2008_part%202.pdf

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Besides the HST and CGRO,there is the Chandra X-ray

Observatory, launched on 23 July 1999 aboard STS-93

and the Space Infrared Telescope Facility (SIRTF)

whose primary mission, as its name implies, is observation

of the infrared spectrum. (The SIRTF, launched

on 25 August 2003 aboard a Delta II rocket, was later

renamed the Spitzer Space Telescope.)77 Aside from

performing each telescope’s own mission, most of which

cannot be replicated by ground observatories, the

Great Observatories program allows the four to

synergistically interact with each other for greater

combined scientific returns.Each astronomical object

in the sky radiates in different wavelengths.

But by training two or more observatories on an object,

combined data can be returned to paint a much more

comprehensive picture than is possible with just a

single instrument.After its deployment from STS-37,

the CGRO operated as advertised for almost a year,

returning more data on that portion of the electromagnetic

spectrum than the previous six decades put together.

But in March 1992, it suffered a failure of its two onboard

tape recorders which restricted downlinks of scientific

data to real time only. With the tape recorders gone,

CGRO was able to relay only slightly more than half of

the science data it collected, because it could not point

at a TDRS all the time. While TDRSS coverage had been

about 65 percent of each orbit, scientists could not

even collect that percentage of data anymore because

Compton’s instruments had to be turned off during the

part of each orbit when it passed through the elevated

background radiation of the South Atlantic Anomaly—a

region of significantly increased space radiation

experienced by satellites passing over the South Atlantic

Ocean. This reduction in data return presented an

obstacle to the Goddard science team. NASA, understandably,

wanted to get back to the point where all of the data could

be retrieved. Furthermore, real-time data dumps could only

be done at the very slow rate of 32 kilobits-per-second

whereas the playback rate was 512 kilobits-per-second.

http://history.nasa.gov/STDN_082508_508%2010-20-2008_part%203.pdf

Tsiao Story NASA Spaceflight Tracking Data Network py5aal part 4.pdf - 890 KB Visualizar

Earth is surrounded by a close-to-spherical

magnetic field, the magnetosphere.According

to what we know today,it is being generated

by actions deep in Earth’s interior where

conducting liquid metals are kept in motion

by the forces of convection, Coriolis

(centrifugal), and gravitation. Just as

the charged windings in the coil of a

generator puts out a magnetic field, these

masses create Earth’s magnetic field. This

field protects the planet from space radiation

by deflecting high energy particles from

deep space or by capturing them in the

Van Allen Belts. Of these belts, discovered

by the first U.S. satellite, Explorer 1 in 1958,

there are two, one closer and the other farther

away. Both surround Earth like a doughnut.

However, at a certain location over the

South Atlantic Ocean between Brazil and Africa,

the shielding effect of the magnetosphere is

not quite spherical but shows a “pothole” or

a dip, which scientists explain as a result

of the offset of the center of the magnetic

field from the geographical center of Earth

(by some 450 kilometers or 280 miles), as well

as the displacement between the magnetic and

geographic poles of Earth.For low-Earth orbiting

satellites inclined between 35 and 60° with

respect to the Equator, this oddity, called

the South Atlantic Anomaly, becomes important

since spacecraft in those orbits periodically

pass through that zone of reduced natural

shielding and thus spend a few minutes during

each orbit exposed to much higher cosmic particle

flux.Thus, vehicles in such orbits require higher

shielding for the crew. It is also of concern in

the design of space-hardened electronics which are

degraded faster by higher particle fluxes.

The design of the International Space Station,

for instance, takes this effect into account.

http://history.nasa.gov/STDN_082508_508%2010-20-2008_part%204.pdf

CHEN Francis F Introduction to Plasma Physics and Controlled Fusion Plasma Physics PY5AAL -. .pdf - 9010 KB Visualizar

http://books.google.com.br/books Controlled+Fusion+Plasma+Physics+-

Kopp, G.; Lawrence, G and Rottman, G.Solar Flares NASA Video from 2003 ( (2005). "The Total Irradiance Monitor (TIM): Science Results". Solar Physics 230: 129–139. doi:10.1007/s11207-005-7433-9.http://adsabs.harvard.edu/abs/2005SoPh..230..129K.