Project Vanguard

Project Vanguard

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Project Vanguard was a program managed by the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 Naval Research Laboratory (NRL), which intended to launch the first artificial satellite
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....

 into Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

 orbit
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...

 using a Vanguard rocket
Vanguard rocket
The Vanguard rocket was intended to be the first launch vehicle the United States would use to place a satellite into orbit. Instead, the Sputnik crisis caused by the surprise launch of Sputnik 1 led the U.S., after the failure of Vanguard TV3, to quickly orbit the Explorer 1 satellite using a Juno...

 as the launch vehicle
Launch vehicle
In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure....

 from Cape Canaveral Missile Annex
Cape Canaveral Air Force Station
Cape Canaveral Air Force Station is an installation of the United States Air Force Space Command's 45th Space Wing, headquartered at nearby Patrick Air Force Base. Located on Cape Canaveral in the state of Florida, CCAFS is the primary launch head of America's Eastern Range with four launch pads...

, Florida.

In response to the surprise launch
Sputnik crisis
The Sputnik crisis is the name for the American reaction to the success of the Sputnik program. It was a key event during the Cold War that began on October 4, 1957 when the Soviet Union launched Sputnik 1, the first artificial Earth satellite....

 of Sputnik 1
Sputnik 1
Sputnik 1 ) was the first artificial satellite to be put into Earth's orbit. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957. The unanticipated announcement of Sputnik 1s success precipitated the Sputnik crisis in the United States and ignited the Space...

on October 4, 1957, the U.S. restarted the Explorer program
Explorer program
The Explorer program is a United States space exploration program that provides flight opportunities for physics, heliophysics, and astrophysics investigations from space. Over 90 space missions have been launched from 1958 to 2011, and it is still active...

, which had been proposed earlier by the Army Ballistic Missile Agency
Army Ballistic Missile Agency
The Army Ballistic Missile Agency was the agency formed to develop the US Army's first intermediate range ballistic missile. It was established at Redstone Arsenal on February 1, 1956 and commanded by Major General John B...

 (ABMA). Privately, however, the CIA and President Dwight D. Eisenhower
Dwight D. Eisenhower
Dwight David "Ike" Eisenhower was the 34th President of the United States, from 1953 until 1961. He was a five-star general in the United States Army...

 were aware of progress being made by the Soviets on Sputnik from secret spy plane imagery. Together with the Jet Propulsion Laboratory
Jet Propulsion Laboratory
Jet Propulsion Laboratory is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. The facility is headquartered in the city of Pasadena on the border of La Cañada Flintridge and Pasadena...

 (JPL), ABMA built Explorer 1 in 84 days and launched it on January 31, 1958. Before work was completed, however, the Soviet Union launched a second satellite, Sputnik 2
Sputnik 2
Sputnik 2 , or Prosteyshiy Sputnik 2 ), was the second spacecraft launched into Earth orbit, on November 3, 1957, and the first to carry a living animal, a dog named Laika. Sputnik 2 was a 4-meter high cone-shaped capsule with a base diameter of 2 meters...

, on November 3, 1957. Meanwhile, the spectacular televised failure of Vanguard TV3
Vanguard TV3
Vanguard TV3 was the first attempt of the United States to launch a satellite into orbit around the Earth. It was a small satellite designed to test the launch capabilities of the three-stage Vanguard rocket and study the effects of the environment on a satellite and its systems in Earth orbit...

on December 6, 1957 deepened American dismay over the country's position in the Space Race
Space Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...

.

On March 17, 1958, Vanguard 1
Vanguard 1
Vanguard 1 was the fourth artificial Earth satellite launched and the first satellite to be solar powered. Although communication with it was lost in 1964, it remains the oldest manmade satellite still in orbit...

became the second artificial satellite successfully placed in Earth orbit by the United States. It was the first solar-powered satellite. Just 152 mm (6 in) in diameter and weighing just 1.4 kg (3 lb), Vanguard 1 was described by then-Soviet Premier Nikita Khrushchev
Nikita Khrushchev
Nikita Sergeyevich Khrushchev led the Soviet Union during part of the Cold War. He served as First Secretary of the Communist Party of the Soviet Union from 1953 to 1964, and as Chairman of the Council of Ministers, or Premier, from 1958 to 1964...

 as, "The grapefruit satellite."

Vanguard 1 is the oldest artificial satellite still in space, as Vanguard's predecessors, Sputnik 1, Sputnik 2, and Explorer 1, have fallen out of orbit.

Project history


In the early 1950s, the American Rocket Society
American Rocket Society
The American Rocket Society began its existence on April 4, 1930, under the name of the American Interplanetary Society. It was founded by science fiction writers G. Edward Pendray, David Lasser, Laurence Manning and others. The members originally conducted their own rocket experiments in New York...

 set up an ad hoc Committee on Space Flight, of which Milton W. Rosen, NRL project manager for the Viking rocket, became chair. Encouraged by conversations between Richard W. Porter of General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

 and Alan T. Waterman, Director of the National Science Foundation
National Science Foundation
The National Science Foundation is a United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health...

 (NSF), Rosen on November 27, 1954 completed a report describing the potential value of launching an earth satellite. The report was submitted to the NSF early in 1955. As part of planning for the International Geophysical Year
International Geophysical Year
The International Geophysical Year was an international scientific project that lasted from July 1, 1957, to December 31, 1958. It marked the end of a long period during the Cold War when scientific interchange between East and West was seriously interrupted...

 (IGY) (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
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...

 (USAF), the United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...

, and the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

. The Army Ballistic Missile Agency
Army Ballistic Missile Agency
The Army Ballistic Missile Agency was the agency formed to develop the US Army's first intermediate range ballistic missile. It was established at Redstone Arsenal on February 1, 1956 and commanded by Major General John B...

 (ABMA) under Dr. Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...

 had suggested using a modified Redstone rocket
Redstone (rocket)
The PGM-11 Redstone was the first large American ballistic missile. A short-range surface-to-surface rocket, it was in active service with the U.S. Army in West Germany from June 1958 to June 1964 as part of NATO's Cold War defense of Western Europe...

 (see: Juno I
Juno I
The Juno I was a four-stage American booster rocket which launched America's first satellite, Explorer 1, in 1958. A member of the Redstone rocket family, it was derived from the Jupiter-C sounding rocket...

) while the Air Force had proposed using the Atlas rocket, which did not yet exist. The Navy proposed designing a rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...

 system based on the Viking
Viking rocket
The Viking rocket series of sounding rockets were designed and built by the Glenn L. Martin Company under the direction of the U.S. Naval Research Laboratory . Twelve Viking rockets flew from 1949 to 1955.- Origins :...

 and Aerobee rocket
Aerobee rocket
The Aerobee rocket was a small unguided suborbital sounding rocket used for high atmospheric and cosmic radiation research in the United States in the 1950s....

 systems.

The Air Force proposal was not seriously considered, as Atlas development was years behind the other vehicles. Among other limitations, the Army submission focused on the vehicle, while a payload was assumed to become available from JPL
Jet Propulsion Laboratory
Jet Propulsion Laboratory is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. The facility is headquartered in the city of Pasadena on the border of La Cañada Flintridge and Pasadena...

, and the network of ground tracking stations was assumed to be a Navy project. Meanwhile, the NRL proposal detailed all three aspects of the mission.

The Navy's project


In August 1955, the US DOD
United States Department of Defense
The United States Department of Defense is the U.S...

 Committee on Special Capabilities chose the Navy's proposal as it appeared most likely, by spring 1958, to fulfill the following:
  1. Place a satellite in orbit during the IGY
    International Geophysical Year
    The International Geophysical Year was an international scientific project that lasted from July 1, 1957, to December 31, 1958. It marked the end of a long period during the Cold War when scientific interchange between East and West was seriously interrupted...

    .
  2. Accomplish a scientific
    Science
    Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

     experiment
    Experiment
    An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...

     in orbit.
  3. Track the satellite and ensure its attainment of orbit.


Another consideration was that the Navy proposal used civilian sounding rocket
Sounding rocket
A sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The origin of the term comes from nautical vocabulary, where to sound is to throw a weighted line from a ship into...

s rather than military missiles, which were considered inappropriate for peaceful scientific exploration. What went unstated at the time was that the U.S. already had a covert satellite program underway, WS-117, which was developing the ability to launch spy satellites using USAF Thor IRBMs. The US government was concerned that the Soviets would object to military satellites overflying the Soviet Union as they had to many aircraft incursions and the balloons of the Genetrix project. The idea was that if a clearly "civilian" and "scientific" satellite went up first, the Soviets might not object, and thus the precedent would be established that space was above national boundaries
Air rights
Air rights are a type of development right in real estate, referring to the empty space above a property. Generally speaking, owning or renting land or a building gives one the right to use and develop the air rights....

.

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 initial funding came from the National Science Foundation
National Science Foundation
The National Science Foundation is a United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health...

. 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
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

http://www.hq.nasa.gov/office/pao/History/sputnik/hagen.html. The initial 1.4 kg spherical Vanguard satellites were built at the NRL, and contained as their payload seven mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...

 cell batteries
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...

 in a hermetically sealed container, two tracking radio transmitters, a temperature sensitive crystal, and six clusters of solar cell
Solar cell
A solar cell is a solid state electrical device that converts the energy of light directly into electricity by the photovoltaic effect....

s on the surface of the sphere.

NRL was also responsible for developing the Vanguard rocket launch vehicles through a contract to the Martin Company (which had built the Viking rockets), developing and installing the satellite tracking system, and designing, constructing, and testing the satellites. The tracking system was called Minitrack
Minitrack
The Minitrack Network, was the first U.S. satellite tracking network to become operational, in 1957. It was used to track the flights of Sputnik, Vanguard, Explorer, and other early space efforts...

. The Minitrack stations, designed by NRL but subcontracted to the Army Corps of Engineers, 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
Air Force Space Surveillance System
The Air Force Space Surveillance System, colloquially known as the Space Fence, is a multistatic radar system that detects orbital objects passing over America...

, which remains operational today under the control of the Air Force and is a major producer of spacecraft tracking data.

Sputnik and Explorer 1


On October 4, 1957, the Vanguard team learned of the launch of Sputnik 1
Sputnik 1
Sputnik 1 ) was the first artificial satellite to be put into Earth's orbit. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957. The unanticipated announcement of Sputnik 1s success precipitated the Sputnik crisis in the United States and ignited the Space...

by the USSR
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 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 2
Sputnik 2
Sputnik 2 , or Prosteyshiy Sputnik 2 ), was the second spacecraft launched into Earth orbit, on November 3, 1957, and the first to carry a living animal, a dog named Laika. Sputnik 2 was a 4-meter high cone-shaped capsule with a base diameter of 2 meters...

, on November 3, 1957, then Secretary of Defense
United States Secretary of Defense
The Secretary of Defense is the head and chief executive officer of the Department of Defense of the United States of America. This position corresponds to what is generally known as a Defense Minister in other countries...

 Neil H. McElroy
Neil H. McElroy
Neil Hosler McElroy was United States Secretary of Defense from 1957 to 1959 under President Eisenhower. He had been president of Procter & Gamble.- Early life :...

 directed the Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...

 to use the Juno I
Juno I
The Juno I was a four-stage American booster rocket which launched America's first satellite, Explorer 1, in 1958. A member of the Redstone rocket family, it was derived from the Jupiter-C sounding rocket...

 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 (1.2 m) into the air when the engine lost thrust, and the rocket immediately sank back down to the launch pad and exploded. The payload nosecone detached and landed free of the exploding rocket, the small satellite's radio beacon still beeping. The failure was widely and creatively derided in the press, being called a 'kaputnik' in the "Daily Express", a 'flopnik' in the "Daily Herald", a 'puffnik' in the "Daily Mail" and a 'stayputnik' in the "News Chronicle".

On February 1, 1958, the US Army launched the Explorer 1 satellite. With the launch of Sputnik 1 & 2 the previous concern, of the right of satellite overflight, had become moot: those satellites were launched by an early version of the Soviet R-7 rocket, the basis of the USSR's early ICBMs, and definitely military, as well as roughly 40 times larger than the Vanguard launcher.

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 kilometers (2466 mi) and a perigee
Perigee
Perigee is the point at which an object makes its closest approach to the Earth.. Often the term is used in a broader sense to define the point in an orbit where the orbiting body is closest to the body it orbits. The opposite is the apogee, the farthest or highest point.The Greek prefix "peri"...

 of 650 kilometers (404 mi). It was estimated that it would remain in orbit for at least 240 years, and it was renamed Vanguard 1, which remains the oldest human-made satellite still in orbit.

In late 1958, with responsibility for Project Vanguard having been transferred to NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

, the nucleus of the Goddard Space Flight Center
Goddard Space Flight Center
The Goddard Space Flight Center is a major NASA space research laboratory established on May 1, 1959 as NASA's first space flight center. GSFC employs approximately 10,000 civil servants and contractors, and is located approximately northeast of Washington, D.C. in Greenbelt, Maryland, USA. GSFC,...

 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. The program ended with the launch of Vanguard 3 in 1959.

Accomplishments


Despite being overshadowed by Sputnik, and having to overcome the widespread humiliation of its unsuccessful early attempts, the Vanguard Project eventually met its scientific objectives, providing a wealth of information on the size and shape of the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

, air density, temperature ranges, and micrometeorite impact. The Vanguard 1 radio continued to transmit until 1964, and tracking data obtained with this satellite revealed that Earth is not quite a perfect sphere: it is slightly pear-shaped, elevated at the North Pole
North Pole
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is, subject to the caveats explained below, defined as the point in the northern hemisphere where the Earth's axis of rotation meets its surface...

 and flattened at the South Pole
South Pole
The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...

. It corrected ideas about the atmosphere's density at high altitudes and improved the accuracy of world maps. The Vanguard program was transferred to NASA when that agency was created in mid-1958.

NRL space scientists say that the Vanguard 1 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 validated in flight that solar cell
Solar cell
A solar cell is a solid state electrical device that converts the energy of light directly into electricity by the photovoltaic effect....

s 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 optical 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 50th year in space on March 17, 2008. In the years following its launch, the small satellite has made more than 196,990 revolutions of the earth and traveled 5.7 billion nautical miles, the distance from Earth to beyond the dwarf planet Pluto
Pluto
Pluto, formal designation 134340 Pluto, is the second-most-massive known dwarf planet in the Solar System and the tenth-most-massive body observed directly orbiting the Sun...

 and halfway back. Original estimates had the orbit lasting for 2000 years, but it was discovered that solar radiation pressure and atmospheric drag during high levels of solar activity produced significant perturbations in the perigee height of the satellite, which caused a significant decrease in its expected lifetime to only about 240 years.

The Vanguard Satellite Launch Vehicle (the term was invented for the operation SLV models, as opposed to the Test Vehicle TV versions) of the first generation. It was a much smaller and lighter launcher than the Jupiter-C
Jupiter-C
The Jupiter-C was an American sounding rocket used for three sub-orbital spaceflights in 1956 and 1957 to test re-entry nosecones that were later to be deployed on the more advanced PGM-19 Jupiter mobile missile....

 (Redstone) which launched the Explorer satellites, or the immense R-7
R-7 Semyorka
The R-7 was a Soviet missile developed during the Cold War, and the world's first intercontinental ballistic missile. The R-7 made 28 launches between 1957 and 1961, but was never deployed operationally. A derivative, the R-7A, was deployed from 1960 to 1968...

 that the Soviets used to launch the early Sputniks. Von Braun has stated (in March 1958) that the Vanguard SLV was one of the most efficient in American history, perhaps the most efficient.

Launch history



Test vehicle launches
The first Vanguard flight, a successful suborbital test of the TV-0 single-stage vehicle, was launched on December 8, 1956. On May 1, 1957, the two-stage test vehicle TV-1 was successfully launched. Vanguard TV-2, another suborbital test, was launched October 23, 1957.

The Vanguard rocket launched three satellites out of eleven launch attempts:
  1. Vanguard TV3
    Vanguard TV3
    Vanguard TV3 was the first attempt of the United States to launch a satellite into orbit around the Earth. It was a small satellite designed to test the launch capabilities of the three-stage Vanguard rocket and study the effects of the environment on a satellite and its systems in Earth orbit...

     - December 6, 1957 - Failed to orbit 1.36 kg (3 lb
    Pound (mass)
    The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...

    ) satellite
  2. Vanguard TV3 Backup - February 5, 1958 - Failed to orbit 1.36 kg (3 lb) satellite
  3. Vanguard 1
    Vanguard 1
    Vanguard 1 was the fourth artificial Earth satellite launched and the first satellite to be solar powered. Although communication with it was lost in 1964, it remains the oldest manmade satellite still in orbit...

     - March 17, 1958 - Orbited 1.47 kg (3.25 lb) satellite
  4. Vanguard TV5 - April 28, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
  5. Vanguard SLV 1 - May 27, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
  6. Vanguard SLV 2 - June 26, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
  7. Vanguard SLV 3 - September 26, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
  8. Vanguard 2
    Vanguard 2
    Vanguard 2 or Vanguard II is an earth-orbiting satellite launched February 17, 1959 aboard a Vanguard SLV 4 rocket as part of the United States Navy's Project Vanguard...

     - February 17, 1959 - Orbited 10.8 kg (23.7 lb) satellite
  9. Vanguard SLV 5 - April 13, 1959 - Failed to orbit 10.3 kg (22 lb 11 oz
    Ounce
    The ounce is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of different systems, including various systems of mass that form part of the imperial and United States customary systems...

    ) satellite
  10. Vanguard SLV 6 - June 22, 1959 - Failed to orbit 10.3 kg (22 lb 11 oz) satellite
  11. Vanguard 3
    Vanguard 3
    Vanguard 3 is a scientific satellite that was launched into Earth orbit by a Vanguard rocket on September 18, 1959, the third successful Vanguard launch out of eleven attempts.-Mission Objectives:...

     - September 18, 1959 - Orbited 22.7 kg (50 lb) satellite

See also

  • Vanguard rocket
    Vanguard rocket
    The Vanguard rocket was intended to be the first launch vehicle the United States would use to place a satellite into orbit. Instead, the Sputnik crisis caused by the surprise launch of Sputnik 1 led the U.S., after the failure of Vanguard TV3, to quickly orbit the Explorer 1 satellite using a Juno...

  • Explorer program
    Explorer program
    The Explorer program is a United States space exploration program that provides flight opportunities for physics, heliophysics, and astrophysics investigations from space. Over 90 space missions have been launched from 1958 to 2011, and it is still active...

  • Sputnik program
  • Sputnik crisis
    Sputnik crisis
    The Sputnik crisis is the name for the American reaction to the success of the Sputnik program. It was a key event during the Cold War that began on October 4, 1957 when the Soviet Union launched Sputnik 1, the first artificial Earth satellite....


External links