Whilst searching for the content of my book i couldn't have stumbled across a source, NASA have a section on their website dedicated to 'The Hubble story', this piece of writing do exactly what it says, it tells the story from the man it is named after up until the launch which is what my publication will cover in the first half, now it's my job to take this information and do the telescope justice with my piece of design.
In the Beginning
Since the dawn of civilization, man was limited by his vision and
imagination about his understanding of the universe. The telescope
enhanced his vision and tempered his pride, as observations by
Copernicus, Galileo and Kepler in the 16th and 17th centuries A.D.
rebuffed the millennia-old conceit that the Earth is the center of the
universe, spearheading the Scientific Revolution.
By the 18th century, the telescope would become the indispensable
instrument for investigations of the cosmos. Bigger and better
telescopes were built all over the world. Planets, stars, and nebulae
which could not be seen by the naked eye were now being routinely noted
and logged. Advances in spectroscopy, photography, and photometry
increased telescope versatility, sensitivity, and discovery power.
Enter Edwin Hubble
By the turn of the 20th century, most astronomers believed that the
observable universe consisted of one galaxy, our Milky Way Galaxy, an
oasis of stars, dust, and gas in the vastness of space. However, in
1924, American astronomer Edwin Hubble used the 100-inch Hooker
Telescope (see image below) on Mount Wilson near Los Angeles,
California, to observe billions of other galaxies besides our own Milky
Way, almost all moving away from each other. This suggested that the
universe is expanding, unleashing a Pandora's box of seminal
inquiries—such as the Big Bang theory—about the possible beginning and
end of the universe—issues which are still being debated to this day.
Image left: American astronomer Edwin Hubble in 1924 - used the 100-inch Hooker Telescope. Image credit: NASA
Astronomers like Edwin Hubble (before and after his time), toiled long,
frigid nights inside enormous dome-shaped "observatories" pointing their
telescopes skyward, yearning for the best possible snapshot of the
heavens. However they faced a major obstacle that stood between them and
a clear view of the universe: the Earth's atmosphere. The Earth's
atmosphere is a fluid, chaotic soup of gas and dust. It blurs visible
light, causing stars to twinkle and making it difficult to see faint
stars. It hinders or even totally absorbs other wavelengths of light,
making observations of such wavelength ranges as infrared, ultraviolet,
gamma rays and X-rays difficult or virtually impossible (it is also
these properties which protect us from the harmful effect of these
rays).
Observatories with the largest of telescopes in various continents have
been perched upon mountain tops and away from distracting city lights,
from Caucasus Mountains in Europe to the Australian outback, with
varying levels of success. Adaptive optics and other image processing
techniques have minimized - but not totally eliminated - the effects of
the atmosphere.
A Telescope in Space?
In 1923, German scientist Hermann Oberth, one of the three fathers of
modern rocketry (Oberth, Robert Goddard and Konstantin Tsiolkovsky),
published "Die Rakete zu den Planetenraumen" ("The Rocket into Planetary
Space"), which mentioned how a telescope could be propelled into Earth
orbit by a rocket. In 1946, Princeton astrophysicist Lyman Spitzer wrote
about the scientific benefits of a telescope in space, above Earth's
turbulent atmosphere.
Following the launch of the Soviet satellite Sputnik in 1957, the
fledgling National Aeronautics and Space Administration (NASA)
successfully launched two Orbital Astronomical Observatories (OAOs) into
orbit. They made a number of ultraviolet observations and provided
learning experiences for the manufacture and launch of future space
observatories.
The LST - Large Space Telescope
Meanwhile, scientific, governmental, and industrial groups planned the
next step beyond the OAO program. Spitzer gathered the support of other
astronomers for a "large orbital telescope" and addressed the concerns
of its critics. In 1969, the National Academy of Sciences gave its
approval for the Large Space Telescope (LST) project, and the hearings
and feasibility studies continued.
After Armstrong's "giant leap for mankind" on the moon in 1969, funding
for NASA space programs began to dwindle, putting the LST program in
jeopardy. LST planners had to design the telescope under budget
constraints. A number of downsizing measures were weighed and
considered: decrease the size of the primary mirror, the number of
scientific instruments, the diameter of the Systems Support Module and
the number of spare parts created and tests performed. In 1974, the LST
Science Working Group recommended the space telescope carry a large
complement of interchangeable instruments. They would have
specifications to resolve at least one-tenth of an arcsecond, and have a
wavelength range from ultraviolet through visible to infrared light.
The Space Shuttle
NASA and its industrial partners—called contractors—brought up the
option of developing a vehicle that could achieve orbit and return to
earth intact and be reused repeatedly; the concept of the Space Shuttle
was born. The Space Shuttle could deploy the LST into space and reel it
back for return to Earth. The shuttle could, and would, be used for a
myriad of other operations for the space program as well.
NASA suggested that the lifetime of the space telescope be fifteen
years, which implied that the instruments needed the ability to be
replaced on the ground or even serviced in orbit—an ability not afforded
to any satellite before or since. Scientists also had to balance the
size and quantity of scientific instruments versus their cost. Too many
instruments meant financial support was less likely; conversely,
instruments of minimal capability would result in the loss of scientific
support for the telescope. The European Space Agency (ESA) joined the
project in 1975 and provided fifteen percent of the funding of the LST
via contribution of the Faint Object Camera (FOC) and the solar arrays.
In return, NASA guaranteed at least fifteen percent of telescope
time—the amount of time astronomers use the telescope for space
observations - to European astronomers. In 1977, Congress approved
funding to build one of the most sophisticated satellites ever
constructed.
Who Does What?
NASA chose Marshall Space Flight Center in Huntsville, Alabama, as the
lead NASA field center for the design, development, and construction of
the renamed Space Telescope (ST). Marshall delegated Perkin-Elmer
Corporation (now, Hughes Danbury Optical Systems) the task of developing
the Optical Telescope Assembly and the Fine Guidance Sensors. Lockheed
Missiles and Space Company (now, Lockheed Martin) was selected by
Marshall to build the cylindrical casing and the internal support
systems (the Support Systems Module) and assembling the telescope
together.
NASA chose Goddard Space Flight Center in Greenbelt, Maryland, to be the
lead in scientific instrument design and ground control for the space
observatory. Scientists were organized into "Instrument Definition
Teams" which would translate scientific aims into scientific devices and
incorporate them into the space telescope housing. After an
announcement was made to the astronomy community, proposals were
received and judged, and five devices were selected as the initial
instruments that would be aboard the Space Telescope: the Faint Object
Camera, the Wide Field/Planetary Camera, the Faint Object Spectrograph,
the High Resolution Spectrograph, and the High Speed Photometer.
The Johnson Space Center in Houston, Texas, and the Kennedy Space Center
in Florida supplied Space Shuttle support. In all, dozens of
contractors, a handful of universities, and several NASA centers,
spanning 21 states and 12 other countries worldwide, made the dream of a
telescope above the clouds and in space a reality.
In 1983, the Space Telescope Science Institute (STScI) was established
at The Johns Hopkins University in Baltimore, Maryland. The staff of
STScI evaluated proposals for telescope time and managed the resulting
telescope observations. A number of delays stemming from underestimating
the costs and engineering requirements of the state-of-the-art
telescope caused the launch date to be moved from December 1983 to the
second half of 1986. NASA re-examined interfaces, instruments, and
assemblies. The building of the Optical Telescope Assembly encountered
engineering challenges. Scientific instruments, like the Wide
Field/Planetary Camera (WF/PC), underwent redesign, removing weight and
redundancy.
Hubble is Born
In regards to the maintenance and upgrading of the space telescope,
plans were made to conduct servicing missions in orbit versus returning
the telescope to Earth and refurbishing it on the ground. It was an
innovative concept that would be even easier on a budget. In the midst
of this spirit of renovation, the Space Telescope was renamed the Hubble
Space Telescope (HST). By 1985, the telescope was assembled and ready
for launch.
However, in 1986 disaster struck. The Challenger accident forced NASA to
ground the Space Shuttle fleet for two years. However, these were years
well spent by the HST Project. Solar panels were improved with new
solar cell technology. The aft shroud was modified to make instrument
replacement during servicing easier. Computers and communication systems
were upgraded. The HST was subjected to further stress tests in the
harsh environments of liftoff and space.
Finally, on April 24, 1990, the Space Shuttle Discovery lifted off from
earth with the Hubble Space Telescope nestled securely in its bay. The
following day, Hubble was released into space, ready to peer into the
vast unknown of space, offering mankind a glimpse upon distant, exotic
cosmic shores yet to be described.
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