6
Engineering Systems Integration
On April 24, 1990, the Hubble Space Telescope* was launched from Kennedy
Space Center, Florida and carried in the Shuttle Orbiter payload bay aboard
the STS-31 mission of the Space Shuttle Discovery. Some three-and-a-half
years later in December 1993, the crew on STS-61 from the Space Shuttle
Endeavor installed subsystems of corrective optics and replaced solar arrays
and gyroscopes, added new instruments and computer equipment, and
extended the space telescope’s lifecycle. This second mission corrected the
problems with initial implementation of the primary mirror (housed within
the Ritchey–Chretien Cassegrain telescope). The optical flaw had reduced
the performance of the telescope’s resolving power. The result had been a
blurring of the images which used the primary mirror (Mattice 2005). The
development and operational teams overcame the engineering and technical obstacles, the external influences, and the political guidance to provide a
magnificent system that was part of a spectacular system of systems (independent researchers from around the world, astronauts, and space shuttle
with its infrastructure support, space tracking network, and the Hubble
Space Telescope (to highlight but a few components)). With new equipment
and improvements brought and implemented by the space shuttle mission
STS-125 in April 2009, the Hubble Space Telescope is expected to continue
operations into 2014. The Hubble Space Telescope was described (Mattice
2005) in terms of its technical characteristics, its mission, and development
and integration issues.
Hubble Space Telescope Description
The primary mirror is a first-surface optical slab 2.4 m in diameter, providing 10 times better resolution than Earth-based telescopes, nominally 0.1
arc-seconds. Several other major telescopes are integrated into the Hubble
Space Telescope’s physical, electrical, thermal, and data electronics structure. Hubble’s dimensions are: length of 13.3 m (43.6 ft) and diameter of
4.3 m (14 ft); its weight (measured at Earth-sea level) is 24,973 lb; its solar
arrays deliver 4400 W; and its data rate to support science is 1 megabits per
second.
Hubble’s mission is to serve as a permanent space-based observatory at
600 km (320 ± 5 nm) altitude (low-Earth orbit) with an orbital inclination of
28.4°. One Earth orbit takes 95 min to complete, and while the Hubble Space
Telescope operates 24 h, seven days a week, not all of the time is spent observing sectors of the sky to support the schedules of observers. Pointing to new
sectors, avoiding the Sun or Moon, switching electronic modes and communicating data (from and to Earth), and calibrating instruments constrain both
the ground support operations and the available “seeing” time.
* In the early days of work on the Hubble Space Telescope, the project was called the Large
Space Telescope (LST) (1973/4).
Engineering Systems Integration
On April 24, 1990, the Hubble Space Telescope* was launched from Kennedy
Space Center, Florida and carried in the Shuttle Orbiter payload bay aboard
the STS-31 mission of the Space Shuttle Discovery. Some three-and-a-half
years later in December 1993, the crew on STS-61 from the Space Shuttle
Endeavor installed subsystems of corrective optics and replaced solar arrays
and gyroscopes, added new instruments and computer equipment, and
extended the space telescope’s lifecycle. This second mission corrected the
problems with initial implementation of the primary mirror (housed within
the Ritchey–Chretien Cassegrain telescope). The optical flaw had reduced
the performance of the telescope’s resolving power. The result had been a
blurring of the images which used the primary mirror (Mattice 2005). The
development and operational teams overcame the engineering and technical obstacles, the external influences, and the political guidance to provide a
magnificent system that was part of a spectacular system of systems (independent researchers from around the world, astronauts, and space shuttle
with its infrastructure support, space tracking network, and the Hubble
Space Telescope (to highlight but a few components)). With new equipment
and improvements brought and implemented by the space shuttle mission
STS-125 in April 2009, the Hubble Space Telescope is expected to continue
operations into 2014. The Hubble Space Telescope was described (Mattice
2005) in terms of its technical characteristics, its mission, and development
and integration issues.
Hubble Space Telescope Description
The primary mirror is a first-surface optical slab 2.4 m in diameter, providing 10 times better resolution than Earth-based telescopes, nominally 0.1
arc-seconds. Several other major telescopes are integrated into the Hubble
Space Telescope’s physical, electrical, thermal, and data electronics structure. Hubble’s dimensions are: length of 13.3 m (43.6 ft) and diameter of
4.3 m (14 ft); its weight (measured at Earth-sea level) is 24,973 lb; its solar
arrays deliver 4400 W; and its data rate to support science is 1 megabits per
second.
Hubble’s mission is to serve as a permanent space-based observatory at
600 km (320 ± 5 nm) altitude (low-Earth orbit) with an orbital inclination of
28.4°. One Earth orbit takes 95 min to complete, and while the Hubble Space
Telescope operates 24 h, seven days a week, not all of the time is spent observing sectors of the sky to support the schedules of observers. Pointing to new
sectors, avoiding the Sun or Moon, switching electronic modes and communicating data (from and to Earth), and calibrating instruments constrain both
the ground support operations and the available “seeing” time.
* In the early days of work on the Hubble Space Telescope, the project was called the Large
Space Telescope (LST) (1973/4).