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Skylab
was the first US space station and the world's first big space station. It was
launched on May 14th, 1973 by a Saturn V Rocket. Skylab Space
Station was
assembled from
Saturn
V
and
Apollo components. Skylab's purpose was to serve as a laborarory
for scientific experiments in space until February 1974.
An
Apollo Spacecraft was used to transport the
crew to Skylab and to return them to the Earth's surface. It was a launched on a
Saturn
1B
rocket.
Skylab was used to study:-
- the Sun.
- microgravity research
- learn more about Earth.
- to test the effects of
long-duration space flights and to
see how the human body reacts in space
- to helped us learn to live and work in space.
- to conduct a variety of
scientific and technological experiments, such as
metallic-crystal growth in the weightless state.
- and function as a
laboratory in earth orbit.
Skylab Specifications:
Structure
Weight: 91 metric ton (100-ton)
Height: 36
metres (118 feet)
Diamater: 6.7
metres (22 feet)
Altitude of Orbit:
435km (270 miles)
Orbital Mass:
77,088kg
Habitable Volume:
283 cubic metres (10,000
cubic feet)
Skylab Space Station was
a modified third stage of a Saturn V moon rocket. Skylab
was actually the refitted S-IVB second stage of a Saturn IB
booster (from the AS-212 vehicle), a leftover from the Apollo
program originally intended for one of the canceled Apollo earth
orbital missions. A product of the Apollo Applications program
(a program tasked with finding long-term uses for Apollo program
hardware).
Skylab consisted of five parts:
- Orbital Workshop
was the living and working area for the crew.
- Airlock Module
was used by the
Astronauts to access
the outside of Skylab for
spacewalks.
- Apollo Telescope
Mount (ATM) was attached
to one end of the cylindrical workshop. It was
used
to study our sun, stars and earth with no atmospheric
interference.
- Multiple Docking
Adapter allowed more than one
Apollo spacecraft to dock to the station at once.
- The Saturn Instrument
Unit (IU) was used by NASA teams in Huntsville to
reprogram the space station using a massive ring of
computers. The unit was used to guide Skylab itself into
orbit. IU also controlled the jettisoning of the protective
payload shroud and activated the onboard life support
systems, started the solar inertial attitude maneuver,
deployed the Apollo Telescope mount at a 90-degree angle and
deployed Skylab's solar wings.
SKYLAB
FLIGHTS
Skylab orbited Earth 2,476
times during the 171 days and 13 hours of its occupation during
the three manned Skylab missions. Astronauts performed ten
spacewalks totalling 42 hours 16 minutes.
Skylab 1 -
May 14, 1973 Unmanned
A two-stage version of the
Saturn V rocket launched Skylab to orbit on
May 14, 1973 from
the NASA Kennedy Space Center, Florida.
During the launch, the station
was damaged. A critical meteoroid shield and one of the
station's two main solar panels were ripped off and the other
solar panel was not fully stretched out. That meant that Skylab
had little electrical power and the internal temperature rose to
126 degrees Fahrenheit (52 degrees Celsius).
Originally it
was planned that a crew would be launched from Earth the next
day to inhabit the space station. Sixty-three seconds after
liftoff, however, a critical meteoroid shield ripped off, taking
one of the craft's two solar panels with it and preventing the
other from deploying properly. Ground command maneuvered Skylab
so its solar panels faced the Sun to provide as much electricity
as possible. But because the meteoroid shield was gone (which
also operated as a sun shield), temperatures inside the workshop
rose to 126˚F (52˚C). The launch of Skylab 2 (the
first crew to inhabit the space station) was postponed for 10
days while scientists, engineers, astronauts, and management
personnel at NASA's Marshall Space Flight Center in Huntsville,
Alabama, and elsewhere developed procedures and trained the crew
to make the workshop habitable. At the same time, engineers
"rolled" Skylab to lower the temperature of the
workshop.
Almost immediately, technical
problems developed due to vibrations during lift-off. A critical
meteoroid shield ripped off taking one of the craft's two solar
panels with it; a piece of the shield wrapped around the other
panel keeping it from deploying. Skylab was maneuvered so its
Apollo Telescope Mount (ATM) solar panels faced the Sun to
provide as much electricity as possible. Because of the loss of
the meteoroid shield, however, this positioning caused workshop
temperatures to rise to 52 degrees Celsius (126 degrees F). The
launch of Skylab 2 was postponed while NASA engineers, in an
intensive 10-day period, developed procedures and trained the
crew to make the workshop habitable. At the same time, engineers
"rolled" Skylab to lower the temperature of the
workshop.
On the first launch, part
of Skylab fell off. It tore one solar panel. It wrapped around
the other panel so it could not open. The crew was supposed to
go up the next day. They had to wait until a way to solve these
problems was found. They flew to Skylab 11 days later. The first
thing they had to do was fix the problems.
Skylab
2
Skylab 2 was launched on May 25,
1973 and landed on June 22, 1973. The mission duration
was 28 days, 50 minutes. This was the first manned mission
to Skylab. They
orbited the Earth 404 times, completed 392 experiment hours, and
carried out three spacewalks totalling six hours, 20 minutes.
The first Skylab crew were:
- Charles C. Conrad Jr.
- Paul J. Weitz
- Joseph P. Kerwin
The first
task was to make repairs. These included positioning of a
parasol sunshade that cooled the inside temperatures to a more
comfortable 75˚F (23.8˚C). By June 4, 10 days after
launch, the workshop was fully operational, and the crew began
to conduct solar astronomy and Earth resources experiments,
medical studies, and student experiments. In the period up to
June 22, when the crew left for home,
Skylab was damaged during
launch on May 25, 1973, but the crew, veteran astronaut Conrad,
Comdr. Joseph P. Kerwin (1932?nbsp; ), and
Comdr. Paul J. Weitz (1932?nbsp; ), all of
the navy, carried out EVA repairs, erected a heat-shielding
canopy over the exterior of the spacecraft, and freed a jammed
solar panel. Their flight lasted 28 days.
INSTALLED SOLAR SHIELD
"PARASOL" FROM SCIENTIFIC AIRLOCK RELEASED SOLAR ARRAY
WING ON EVA DOUBLED PREVIOUS LENGTH OF TIME IN SPACE
The first crew was launched 10
days later to fix the ailing station. The astronauts stretched
out the remaining solar panel and set up an umbrella-like
sunshade to cool the station.
Joe Kerwin was on the
first Skylab crew. He said that the first 2 weeks on the station
were very hard. They did not have enough power to run things.
They didn’t even have enough power to make coffee! The crew
had to change their plans until everything was fixed. Once the
power was running, the crew could start the real work on Skylab.
Skylab 3
Skylab 3 was launched on July
28, 1973 and landed on September 25, 1973. This was the second
Skyab maned mission. The mission duration was 59 days, 11 hours.
The crew
completed 858 Earth orbits and 1,081 hours of solar and Earth
experiments and carried out three spacewalks totalling 13 hours,
43 minutes.
The second crew were:
- Alan L. Bean
- Jack R. Lousma
- Owen K. Garriott
After an
early bout of motion sickness, they continued the work of the
previous crew. Garriott and Lousma deployed a second sun shield
during a spacewalk that lasted six and a half hours.
The second crew also had
a problem. On the way up, Jack Lousma looked out the window. He
thought he saw a nozzle floating by. It wasn’t. It was a piece
of ice. That ice showed there was a problem. There was a leak in
the engine. Once the crew was on the station, another engine
started leaking. People on the ground were afraid that the crew
might not be able to come home. A rescue mission was planned.
Two astronauts would fly to Skylab to bring the crew back home.
But, they didn't have to go. The capsule that took the crew to
Skylab was able to bring them home safely.
Installed twinpole solar
shield durng space walk, performed major inflight
maintenace, doubled prvious length of time in space.
Skylab
4
Skylab 4 was
lauched on November 16, 1973 and landed on February 8, 1974.
This was the final mamed mission to Skylab. The mission duration
was 84 days, 1 hour.
At 84 days and 1
hour, Skylab 4 remains the longest U.S. spaceflight to date. The
crew completed 1,214 Earth orbits and four spacewalks totalling
22 hours, 13 minutes. Increased previous length in space by 50%.
The last skylab crew were:
- Gerald P. Carr
- William R. Pogue
- Edward G. Gibson
The crew used
a treadmill in addition to the on-board bicycle-like ergometer
to help stay in shape. The last of the Skylab missions, its
experiments. They observed and photgraphed Comet Kohoutek.
The Skylab project was
considered completely successful. More than 740 hr were spent in
observing the sun by telescopes, and 175,000 solar pictures were
returned to earth, as were about 64 km (about 40 mi) of
electronic data tape and 46,000 photographs of the earth’s
surface. On July 11, 1979, during its 34,981st orbit, Skylab
plunged to earth, raining fiery debris over sparsely populated
western Australia and over the Indian Ocean.
during the three manned Skylab missions.
When the flight of the third crew was finished,
Skylab was abandoned. Skylab remained aloft until intense solar flare activity
caused its orbit to decay sooner than expected. Skylab re-entered the Earth's
atmosphere and burned over Australia in 1979.
Following the last mission the Station was
positioned in a parking orbit expected to last at least 8 years. Increased solar
activity heating the outer layers of the earth's atmosphere and thereby
increasing drag on the Station led to an early reentry on July 11, 1979. Skylab
disintegrated over Western Australia and the Indian Ocean, casting large pieces
of debris in populated areas (fortunately, the only casualty being an Australian
cow). The reentry prevented any further use by the then unfinished Space Shuttle
as was envisioned by some at NASA.
After all crew activities had
been completed and the crews had returned to Earth, Skylab was positioned into a
stable attitude and systems were shut down. It was expected that Skylab would
remain in orbit for eight to ten years. However, in the fall of 1977, Skylab was
no longer flying in a stable attitude as a result of greater than predicted
solar activity. On July 11, 1979, the empty Skylab spacecraft returned to Earth,
scattering debris from the south-eastern Indian Ocean across a sparsely settled
region of western Australia. NASA and the U.S. space program were criticized for
allowing this to happen-ranging from the sale of hardhats as "Skylab
Survival Kits" to serious questions about the propriety of space flight
altogether if people were likely to be killed by falling debris. It was an
inauspicious ending to the first American space station, not one that its
originators had envisioned. Nevertheless, the experiment had whetted the
appetite of NASA leaders for a permanent presence in space
On the 11th July, 1979, Skylab
re-entered the Earth's atmoshpere and scattered debris over the Indian Ocean and
the sparsely settled region of Western Australia.
conclsuion
Three crews visited Skylab.
Each of the Skylab crews set new time records. The
last crew set a record that was not broken for over 20 years.
Did you know?
* Two flight-quality Skylabs were built. The
second (backup) is on display at the National Air and Space Museum in
Washington, DC, USA.
* Skylab was
launched in one launch and required no assembly. The International
Space Station (ISS) will take many years to put together in orbit.
* Skylab was the
first and only United States
Space Station to date. The
ISS involves many countries.
A POST-APOLLO
PROGRAM
In 1969 a Space Task Group recommended to President Richard Nixon a space
program to follow the missions to the Moon. The plan included a permanently
occupied space station, a reusable shuttle spacecraft, and eventual missions to
Mars. But because of increasing budget pressures these ideas received little
political or public support. Only the Space Shuttle won favor and funding, and
even that decision was controversial.
When the last two Apollo missions were cancelled, NASA used some of the
remaining Apollo hardware for an experimental space station, Skylab, as an
interim program before the Shuttle was ready to fly.
Although the STS-107 spiders were the first
Australian animals in space, they weren't the first spiders in space. Anita and
Arabella, two female cross spiders (Araneus diadematus) went into orbit
in 1973 for Skylab 3 space station. Like the STS-107 experiment, the Skylab
experiment was a student project. Judy Miles, from Lexington, Massachusetts,
wanted to know if spiders could spin webs in near-weightlessness. Here is Judith
Miles:
In zero gravity, a lot of things
tumble, roll, flip and tip. Can you name something that spins in
zero-gravity? Hint: it has eight legs and would scare Miss Muffet.
That's right: a spider. In this
case, two of them. Anita and Arabella took off into space way back
in 1973. They were on board Skylab, an early, experimental
orbiting space station. Also on board were 720 fruit flies, six
mice, two minnows and 50 minnow eggs! Busy place.
What was this creature-zoo up to?
They were all part of student experiments. Anita and Arabella were
onboard for high school student Judy Miles from Lexington,
Massachusetts. Judy wondered if spiders could spin webs in
weightlessness. Good question.
So, the lucky student got to team
up with NASA space scientists to design an experiment that would
measure how well spiders weave their webs in space.
So what did Judy and NASA learn?
Zero gravity didn't stop Anita and Arabella from doing what
spiders do -- spin webs.
This little bit of
first spider in space
Spiders have been astronauts in space missions. In
1973, the two common cross spiders "aranous diadematus" Arabella and
Anita became famous for their stay in the Skylab space station.
Both spiders were successful in
spinning webs in weightlessness; examples can be seen in above
images.
Unfortunately, these two spiders
did not return safely: Anita died in-flight before returning, and
Arabella was found dead after splash-down of the Skylab-3 (2nd
manned mission) Apollo CM.
Arabella and Anita have the right stuff. These two
common spiders were NASA’s first eight-legged astronauts! Anita and Arabella
got their mission because a high-school student named Judy Miles wondered if
spiders could spin webs in a weightless environment. She suggested sending
spiders into space to find out. NASA space scientists liked her proposal and
went to work designing special cages, lights, and cameras.
On August 5, 1973, Arabella and Anita blasted off into space on Skylab II.
On her first day in orbit, Arabella didn’t do well. She spun sloppy webs and
obviously felt the effects of weightlessness. However, by her third day in
space, she was spinning just as though she were back at home. Her webs were
finer in space, which was expected. But the pattern remained the same. She
proved that spiders can spin nearly Earth-like webs in space.
Though Arabella and Anita have both died, their bodies remain at the
Smithsonian, memorialized for their small, vital part in increasing our
knowledge of space.
*
Think you are a space expert? Why not test your
knowledge with "Space Trivia," the latest book by Skylab astronaut Bill Pogue.
- Visit
Countdown
Creations
and enter code "aeroshop" for 10% off
all products.
Skylab
Links:
Reference:
Source of
Pictures: http://history.nasa.gov/SP-400/ch1.htm
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