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Space 1
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Table of Contents
1. Introduction
2. 12 advanced, high-risk technologies in space
3. NASA Glenn Research Center
4. Deep Space 1 fly-by
5. Results
6. Conclusion
7. Bibliography
Abstract
The paper discusses the functioning of Deep Space 1. Basically,
the testing of 12 advanced technologies and the fly-by of
the spacecraft is in the focus of the attention of the paper.
At the same time, a brief historical review of the NASA Glenn
Research Center provides an opportunity to better understand
that Deep Space 1 is the product of a hard work of different
generations of scientists, while technologies tested are extremely
important to the further development of spacecrafts and space
exploration
Introduction
The research of the space was traditionally one of the major
priorities of leading countries of the world. No wonder that
the US also focuses on the development of programs targeting
at the research of the space. Moreover, at the present moment
the US achievements in this field are really impressive and
this country occupies the leading position in the world in
regard to the exploration of space.
At the same time, it is worthy of mention that, to a significant
extent, the recent successes of the US researches are predetermined
by the successful implementation of new technologies and the
creation of newest spacecrafts. In this respect, it is necessary
to underline that the spacecraft named Deep Space 1 was one
of the most successful projects launched by NASA within the
last decade. Even though Deep Space has already stopped its
functioning the achievements of its mission were extremely
significant because due to Deep Space 1 12 newest technologies
were successfully tested in space and, it is necessary to
underline that practically all tests were quite risky since
as some specialists estimate almost anything on Deep Space
1 might go wrong (4). Anyway, Deep Space 1 provide an excellent
example of successful use of modern spacecrafts for the research
of space and testing the most sophisticated technologies,
which often cannot be fully tested on the Earth. This is why
it is extremely important to trace the history of Deep Space
1, its achievements and results of work, in order to fully
understand the significance of such project for the further
scientific researches.
12 advanced, high-risk technologies in space
Basically, one of the major objectives of Deep Space 1 was
to test new advanced technologies in space and the fulfillment
of this mission was extremely important. It should be pointed
out that the tests were quite complicated because the technologies
tested were really innovative and there had been no other
similar tests of these technologies before. Nevertheless Deep
Space 1 managed to test 12 advanced technologies that may
be considered the great success of its mission.
Speaking about the technologies tested, it is primarily necessary
to name solar electric propulsion. It should be said that
the basic goal of the test of solar electric propulsion was
to assess the effectiveness of the NSTAR ion thruster developed
at NASA. It turned out that it can achieve better results
compared to traditional space propulsion methods that could
naturally contribute to mass savings of approximately half
(6) that was and still is extremely important in the conditions
of space flights and space research because the weight is
extremely important to space crafts since it can dramatically
limit the distance and time of space expeditions. Moreover,
the successful test of solar electric propulsion that proved
its effectiveness contributes to its wider implementation
that can make cheaper launch vehicles.
It is also necessary to underline that Deep Space 1 successfully
tested the Solar Concentrator Arrays. It should be said that
powering of the engine of Deep Space 1 was the SCARLET (Solar
Concentrator Array of Refractive Linear Element Technologies)
solar arrays. The SCARLET combined with more efficient, dual-junction
cells, turned to be able to generate 2.5 kilowatts with less
size and weight than conventional arrays.
Furthermore, it should be said that Deep Space 1 successfully
used Autonomous navigation system which provided the opportunity
to the spacecraft to determine its position by tracking asteroids
across the star background. At the same time, the system made
it possible to track the position of space objects in relation
to the spacecraft. This technology may be actually used to
acquire targets for the scientific instruments (3).
It should be said that Deep Space 1 also used other absolutely
innovative technologies, such as the Remote Agent which was
the first artificial intelligence control system used to control
the spacecraft without human supervision. The tests conducted
due to Deep Space 1 proved the fact that the Remote Agent
does have the ability to plan onboard activities and correctly
diagnose and respond to faults in the spacecraft components.
The functioning of Deep Space 1 also provided an opportunity
to test the Beacon Monitor Operations. During the long cruise
period of the mission, the spacecraft operations are essentially
suspended. Due to the use of the Beacon Monitor the spacecraft
emits the carrier signal on a predetermined frequency. In
the results of the tests, it was found out that the Beacon
Monitor can function effectively and if the spacecraft detects
an anomaly, it changes the carrier between four tones, based
on urgency. As the carrier may be detected by much simpler
ground antennas and receivers, the signal operators ca divert
DSN resources that prevents skilled operators and expansive
hardware from babysitting an unburdened mission operating
nominally.
The Small Deep Space Transponder was also successfully tested
due to Deep Space 1. In actuality, it was a compact radio
communications system which improves the effectiveness of
communication compared to traditional means of communication
used in the past. Aside from using miniaturized components,
the Small Deep Space Transponder turned to be capable of communicating
over the Ka band which was also successfully tested by Deep
Space 1 and proved its efficiency compared to conventional
means. The main advantage of the Ka band is quite obvious.
Since this band is higher in frequency than conventional bands,
the same amount of data can be sent by smaller equipment in
space and on the ground.
Furthermore, it should be said that Deep Space 1 turned to
be able to function efficiently, not in the last turn, due
to the use of the Plasma Experiment for Planetary Exploration
(PEPE). Once at a target, Deep Space 1 sensed the particle
environment with the PEPE instrument. It mapped the objects
with the MICAS (Miniature Integrated Camera and Spectrometer)
imaging channel, and discerned chemical composition with infrared
and ultraviolet channels. All channels shared a 10 centimeter
telescope which used a silicon carbide mirror.
Also, it is worthy of mention that several other technologies
were also successfully tested due to the use of Deep Space
1. among these technologies may be named Low Power Electronic,
Power Actuation and Switching Module, which basically targeted
at the minimization and more effective use of power by the
spacecraft and which actually proved their efficiency, as
well as the Multifunctional Structure applied to Deep Space
1 did, which testing was also extremely important because
it was a really innovative structure that was characterized
by the capability to fulfill a variety of functions practically
autonomously.
In such a way, Deep Space 1 provided an opportunity to test
the new advanced technologies.
NASA Glenn Research Center
Basically, all the achievements of the mission of Deep Space
1 were the result of work of NASA Glenn Research Center which
actually prepared this project and successfully realized it.
Initially the Glenn Research Center was established in 1942
as a part of the National Advisory Committee for Aeronautics
and was later incorporated into the NASA as a laboratory for
spacecrafts engine research. Throughout its history it has
changed its name several times being initially the Aircraft
Engine Research Laboratory, after funding approval was given
in 1940. Later it was renamed the Flight Propulsion Research
Laboratory in 1947. Than, in 1958, it became the NASA Lewis
Research Center and, finally, in 1999, the NASA Lewis Research
Center was officially renamed the NASA Glenn Research Center.
Obviously, the NASA Glenn Research Center has achieved really
great result. It should be said that it is due to the work
of the center the development and the realization of the project
of the Deep Space 1 was successfully implemented. The vast
majority of the equipment and new technologies were developed
in this center and the advanced technologies that were tested
by Deep Space 1 were also the product of the NASA Glenn Research
Center.
Nevertheless, the achievements of the NASA Glenn Research
Center are not limited by the technologies developed for and
tested by Deep Space 1 only. In fact, the NASA Glenn Research
Center developed various technologies and equipment that were
largely used by NASA in different programs. In this respect,
it is worthy of mention that the liquid hydrogen rocket engine
was developed by the Glenn Research Center. It should be said
that specialists underline that this rocket engine was credited
as being the critical technology leading to the Apollo moon
landing (4). Furthermore, the Glenn Research Center also developed
the famous Centaur Upper Stage Rocket. Also, it should be
said that the technologies developed for Deep Space 1 are
considered to be among the greatest achievements of the Glenn
Research Center but, the center has not stopped its work.
Instead, nowadays, it keeps progressing and among its most
recent achievements may be named the development of the Electrical
Power System for Space Station Freedom, which, except for
minor modifications, is currently used on the International
Space Station. This is why it is possible to estimate that
the Glenn Research Center continues its traditions of the
development of advanced and sophisticated technologies which
contribute substantially to the exploration of the space and
increase the efficiency of space flights and functioning of
equipment in the space. This filed is obviously extremely
perspective for the further development that makes it possible
to speak about good perspectives of the future progress of
the Glenn Research Center.
Deep Space 1 fly-by
Obviously, the mission of Deep Space 1 may be considered to
be quite successful since it provided the opportunity to test
the 12 advanced technologies discussed above, but this was
not the only success or achievement of Deep Space 1. In fact,
it is necessary to underline that a substantial part of the
general success of Deep Space 1 was predetermined by the spacecraft
fly-by.
In this respect, it should be said that Deep Space fly-by
was associated with the fly-by asteroid of Braille and the
comet of Borelly. However, it is necessary to underline that
the fly-by of Braille was only partial success. Initially,
Deep Space 1 was intended to perform the fly-by at 56,000
km/h at only 240 meters from the asteroid, but, due to technical
difficulties, including a software crash shortly before approach,
the spacecraft instead passed Braille at a distance of 26
km. This fact, along with the asteroid’s lower albedo,
meant that Braille was not bright enough for the autonomous
navigation to focus the camera in the right direction, and
the picture shoot was delayed by almost an hour. As a result,
the pictures received were disappointingly indistinct.
In stark contrast to the fly-by of Braille, the fly-by of
the comet Borrelly was a great success and returned extremely
detailed images of the comet’s surface. These images
were of a higher resolution than the only previous pictures
taken by other spacecrafts, such as Giotto. Moreover, the
PEPE instrument reported that the comet’s fields were
offset from the nucleus. This is believe to be due to the
emission of jets, which were not distributed evenly across
the comet’s surface.
Despite the fact that Deep Space 1 had no debris shields,
the spacecraft survived the comet passage intact. However,
Deep Space 1 could not function for a long time after the
fly-by of the comet Borrelly. Even though the sparse comet
jets did not appear to point towards the spacecraft, Deep
Space 1 eventually went dead when it ran out of hydrazine
fuel for its steering thrusters. Without these thrusters,
the spacecraft could not maintain the pointing of its solar
arrays toward the Sun and, thus, the future of Deep Space
1 was determined. As a result, NASA decided not to pursue
a further extended mission after the Borrelly encounter, and
on December 18, 2001, Deep Space 1 was switched off and left
to orbit the Sun. In such a way, the active history of this
spacecraft ended.
Results
Unquestionably, despite certain problems that Deep Space have
faced while fulfilling its mission, the general results of
the functioning of this spacecraft may be assessed positively.
On analyzing the results of work of Deep Space 1, it should
be pointed out that the spacecraft provided important information
about the comet Borrelly in the result of the successful fly-by.
However, this fly-by provided not only distinct pictures of
the comet but it also provided an opportunity to test the
equipment and practice the fly-by at large.
At the same time, it should be said that the testing of new
technologies was also of a paramount importance and may be
viewed as major achievements of Deep Space 1. In this respect,
it should be said that even though the ion propulsion engine
initially failed after 4.5 minutes of operation, but it was
later restored to action and performed excellently (2).
Furthermore, it was thought that the ion exhaust might interfere
with other spacecraft systems, such as radio communications
or the science instruments. The PEPE detectors had a secondary
function to monitor such effects from the engine and, fortunately,
no such interferences were found.
However, there was another failure when the star tracker was
lost. The star tracker determines spacecraft orientation by
comparing star fields to its internal charts. The mission
was saved when the MICAS camera was reprogrammed to stand
in for the star tracker. In such a way, this problem was successfully
solved demonstrating the effectiveness of technologies applied
in Deep Space 1. Nonetheless, it is worthy of mention that
although MICAS camera is more sensitive, its field-of-view
is an order of magnitude smaller, creating a higher processing
burden. Ironically, the star tracker was an off-the-shelf
component that was expected to be highly reliable.
Also, it should be said that the Autonomous navigation system
required some manual corrections, mostly for problems with
identifying of objects which were not bright enough or were
difficult to identify because of the interference of light.
Objects within the field generated spurious reflections into
the instrument. Furthermore, MICAS was a great design success
but it also had certain problems as the ultraviolet channel
failed due to an electrical fault.
However, regardless certain problems the results of tests
and functioning of Deep Space 1 were very important and useful
since they provided scientists not only with important information
but also with essential experience. In such a situation, even
the failures of the mission turned to be useful as they enlarged
the scientists’ experience and knowledge. Obviously,
this experience was worthy of the budget of the mission which
total cost approaches $150 million, including almost $95 million
of development cost (5).
Conclusion
Thus, taking into account all above mentioned, it is possible
to conclude that Deep Space 1 was an extremely important project
that contributed greatly to the enlargement of human knowledge
about space and spacecrafts effective functioning. It also
provided an opportunity to test 12 advanced and new technologies
which reliability was tested in the conditions of space flight.
At the same time, it was not the only success of Deep Space
1. It is necessary to underline that the fly-by of the comet
Borrelly was another major success of the mission even though
it was the last one.
Bibliography:
1. NASA Report, Deep Space 1 Launch Press Kit. Accessed at:
http://www2.jpl.nasa.gov/files//misc/ds1launchq.pdf. -right
click to download pdfs!
2. NASA Report, The successful conclusion of the Deep Space
1 Mission: important results without a flashy title. Accessed
at: http://techreports.jpl.nasa.gov/2002/02-2512.pdf. -right
click to download pdfs!
3. NASA Report, Deep Space One: Preparing for Space Exploration
in the 21st Century. Accessed at: http://techreports.jpl.nasa.gov/1998/98-1347.pdf.
-right click to download pdfs!
4. NASA Report, Deep Space 1 Fact Sheet. Accessed at: http://www.jpl.nasa.gov/news/fact_sheets/ds1.pdf.
-right click to download pdfs!
5. NASA Report, Deep Space 1 Asteroid Flyby Press Kit. Accessed
at: http://www.jpl.nasa.gov/news/press_kits/ds1asteroid.pdf.
-right click to download pdfs!
6. NASA Report, Deep Space 1 flight experience: adventures
on an ion drive. Accessed at: http://techreports.jpl.nasa.gov/2002/02-0276.pdf.
-right click to download pdfs!
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