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Project Vanguard

2007 Schools Wikipedia Selection. Related subjects: Space transport

   Vanguard Rocket
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   Vanguard Rocket

   Project Vanguard was the name given to the first United States program
   that was commissioned to design and launch the first artificial
   satellite into Earth orbit. The surprise launch of Sputnik I on October
   4, 1957 shocked the U.S. and led to the start of a parallel crash
   program by the U.S. Army, that eventually launched the first U.S.
   satellite, Explorer I. The spectacular televised failure of Vanguard
   TV3 on December 6, 1957 deepened American dismay near the height of the
   Cold War.

   On March 17, 1958 Vanguard I became the second artificial satellite
   successfully placed in Earth orbit by the United States. It was the
   first solar-powered satellite. Just 152 mm (six inches) in diameter and
   weighing just 1.4 kg (3 pounds), Vanguard I was described by then-
   Soviet Premier Nikita Khrushchev as "the grapefruit satellite."

   Vanguard I is the oldest human-launched object still in space.
   Vanguard's predecessors, Sputniks 1 and 2 and Explorer I have long
   since fallen out of orbit.

Project history

   As part of planning for the International Geophysical Year (1957 -
   1958), the U.S. publicly undertook to place an artificial satellite
   with a scientific experiment into orbit around the Earth.

The three services' proposals

   Proposals to do this were presented by the United States Air Force, the
   United States Army, and the United States Navy. The Army's ABMA under
   Dr. Wernher von Braun had suggested using a modified Redstone rocket
   (see: Juno I) while the Air Force had proposed using the Atlas rocket,
   which did not yet exist. The Navy proposed designing a rocket system
   based on the Viking and Aerobee rocket systems, for the purposes of
   launching the first US satellite.

   In August 1955, The DOD Committee on Special Capabilities chose the
   Navy's proposal as it appeared most likely to, by spring 1958, fulfill
   the following:
     * 1) place a satellite in orbit during the IGY
     * 2) accomplish a scientific experiment in orbit
     * 3) track the satellite and ensure its attainment of orbit

   Another consideration was that the Navy proposal used civilian rockets
   rather than military missiles, which were considered inappropriate for
   peaceful scientific exploration. Designated Project Vanguard, the
   program was placed under Navy management and DoD monitorship. The Naval
   Research Laboratory (NRL) in Washington was given overall
   responsibility, while funding came from the National Science
   Foundation. The director was John P. Hagen (1908-1990), an astronomer
   who in 1958 would become the assistant director of space flight
   development with the formation of NASA . The 1.4 kg spherical Vanguard
   satellites (designated "Test Vehicles" prior to launch) were built at
   the NRL, and contained as their payload seven mercury cell batteries in
   a hermetically sealed container, two tracking radio transmitters, a
   temperature sensitive crystal, and six clusters of solar cells on the
   surface of the sphere.

   NRL was also responsible for developing the launch vehicles, developing
   and installing the satellite tracking system, and designing,
   constructing, and testing the satellites. The tracking system was
   called Minitrack. The Minitrack stations, designed, built, and
   initially operated by NRL, were along a North-South line running along
   the east coast of North America and the west coast of South America.
   Minitrack was the forerunner of another NRL-developed system called
   NAVSPASUR, which remains operational today under the control of the Air
   Force and is a major producer of spacecraft tracking data.

Sputnik and Explorer I

   TV-3 on display at NASM
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   TV-3 on display at NASM

   On October 4, 1957, the Vanguard team learned of the launch of Sputnik
   I by the USSR while still working on a test vehicle (TV-2) designed to
   test the first stage of their launcher rocket. After the Soviet Union
   launched Sputnik II, on November 3, 1957, the Secretary of Defense
   directed the Army to use the Juno I and launch a satellite. At 11:45 AM
   on December 6 an attempt was made to launch TV-3; the rocket rose about
   four feet into the air, then immediately sank back down to the launch
   pad and exploded. The payload nosecone detached in the process and
   landed free of the exploding rocket. The satellite was too damaged for
   further use; it now resides in the National Air and Space Museum. On
   February 1, the ABMA managed to launch the Explorer I satellite.

   On March 17, 1958, the program successfully launched the Vanguard
   satellite TV-4. TV-4 achieved a stable orbit with an apogee of 3,969 km
   (2466 miles) and a perigee of 650 km (404 miles) ; it was estimated
   that it would remain in orbit for 240 years, and Vanguard 1 remains the
   oldest human-made satellite still in orbit at this time. The radio
   continued to transmit until 1964, and tracking data obtained with this
   satellite revealed that Earth is not quite round - it is elevated at
   the North Pole and flattened at the South Pole. The Vanguard program
   was transferred to NASA when that agency was created in mid-1958. The
   program ended with the launch of Vanguard 3 in 1959.

   In late 1958, with responsibility for Project Vanguard having been
   transferred to NASA, the nucleus of the Goddard Space Flight Centre was
   formed. After the transfer, NRL rebuilt their spacecraft technology
   capability and have developed some 87 satellites over the past 40 years
   for the Navy, DoD and NASA.

Accomplishments

   Vanguard met 100 percent of its scientific objectives, providing a
   wealth of information on the size and shape of the Earth, air density,
   temperature ranges, and micrometeorite impact. It proved that the Earth
   is slightly pear-shaped, not perfectly round; corrected ideas about the
   atmosphere's density at high altitudes and improved the accuracy of
   world maps.

   NRL space scientists say that the Vanguard I program introduced much of
   the technology that has since been applied in later U.S. satellite
   programs, from rocket launching to satellite tracking. For example, it
   proved that solar cells could be used for several years to power radio
   transmitters. Vanguard's solar cells operated for about seven years,
   while conventional batteries used to power another on-board transmitter
   lasted only 20 days.

   Although Vanguard's solar-powered "voice" became silent in 1964, it
   continues to serve the scientific community. Ground-based tracking of
   the now-inert Vanguards continues to provide information about the
   effects of the Sun, Moon and atmosphere on satellite orbits. Vanguard I
   marked its 48th year in space on March 17, 2006. In the years following
   its launch, the small satellite has made more than 178,061 revolutions
   of the Earth and traveled over 9.4 billion km (5.1 billion nautical
   miles).

Launch history

   Vanguard rocket explodes shortly after launch at Cape Canaveral
   (December 6, 1957).
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   Vanguard rocket explodes shortly after launch at Cape Canaveral (
   December 6, 1957).

   The Vanguard rocket launched 3 satellites out of 11 launch attempts:
     * Vanguard TV3 - December 6, 1957 - Failed to orbit 1.36 kg (3 lb)
       satellite
     * Vanguard TV3 Backup - February 5, 1958 - Failed to orbit 1.36 kg (3
       lb) satellite
     * Vanguard 1 - March 17, 1958 - Orbited 1.47 kg (3.25 lb) satellite
     * Vanguard TV5 - April 28, 1958 - Failed to orbit 9.98 kg (22 lb)
       satellite
     * Vanguard SLV 1 - May 27, 1958 - Failed to orbit 9.98 kg (22 lb)
       satellite
     * Vanguard SLV 2 - June 26, 1958 - Failed to orbit 9.98 kg (22 lb)
       satellite
     * Vanguard SLV 3 - September 26, 1958 - Failed to orbit 9.98 kg (22
       lb) satellite
     * Vanguard 2 - February 17, 1959 - Orbited 23.7 lb (10.8 kg)
       satellite
     * Vanguard SLV 5 - April 13, 1959 - Failed to orbit 10.3 kg (22 lb 11
       oz) satellite
     * Vanguard SLV 6 - June 22, 1959 - Failed to orbit 10.3 kg (22 lb 11
       oz) satellite
     * Vanguard 3 - September 18, 1959 - Orbited 22.7 kg (50 lb) satellite

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