Sputnik 1

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Sputnik 1 "Спутник-1"
Organization:	Council of Ministers of the USSR
Major Contractors:	OKB-1, Soviet Ministry of Radiotechnical Industry
Mission type:	Atmospheric studies
Satellite of:	Earth
Launch Date:	October 4, 1957, 19:28:34 UTC (22:28:34 MSK)
Launch Vehicle:	R-7
Decay:	January 4, 1958
Mission Duration:	3 months
NSSDC ID:	1957-001B
Webpage:	NASA NSSDC Master Catalog
Mass:	83.6 kg
Semimajor Axis:	6,955.2 km
Eccentricity:	.05201
Inclination:	65.1°
Orbital Period:	96.1 minutes
Apoapsis:	939 km
Periapsis:	215 km
Orbits:	1,440
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Sputnik 1 (Russian: "Спутник-1", "Satellite-1", byname ПС-1 (PS-1, i.e. "Простейший Спутник-1", or Elementary Satellite-1)) was the first artificial satellite to be put into geocentric orbit. The satellite helped to identify the density of high atmospheric layers by its orbit change and provided data on radio-signal distribution in the ionosphere. Because the satellite's body was filled with pressurized nitrogen, Sputnik 1 also provided the first opportunity for meteoroid detection as losses in internal pressure due to meteoroid penetration of the outer surface would have been evident in the temperature data. Sputnik 1 pioneered Soviet Sputnik program and ignited the so-called Space Race within the Cold War.

Sputnik-1 was set in motion during the International Geophysical Year from the 5th Tyuratam range in Kazakh SSR (now Baikonur Cosmodrome). The satellite travelled at 29000 kilometers (18000 mi) per hour and emitted radio signals at around 20.005 and 40.002 MHz^[1] which were received by scientists and ham radio operators throughout the world. The signals continued until the transmitter batteries ran out on October 26, 1957.^[2] Sputnik 1 burned as it fell from orbit upon reentering Earth's atmosphere, after about 60 million km, made while orbiting.

Contents 1 Prior to launch 2 Design 3 Mission 4 Feedback 5 Controversy surrounding re-entry 6 Trivia 7 Replicas 8 Notes 9 See also 10 External links 10.1 Authentic recordings of the signal 10.2 Primary sources 10.3 Miscellaneous

[edit] Prior to launch

History of Sputnik 1 project dates back to May 26, 1954, when Sergei Korolev addressed Dmitry Ustinov, then Minister of Defense Industries, proposing development of the Earth's artificial satellite and forwarding him a report by Mikhail Tikhonravov with an overview of such works abroad.^[3] Tikhonravov underlined, that artificial satellite is inevitable stage of rocket equipment development, after which interplanetary communication would become possible. ^[4] On July 29, 1955 the U.S. President Dwight Eisenhower announced through his press-secretary, that the United States would launch an artificial satellite during the IGY.^[5] A week later, on August 8 the Presidium of the Central Committee of the CPSU approved the idea of creation of the artificial satellite.^[6] On August 30 a meeting was held by Vasily Ryabikov, the head of the State Commission on R-7 rocket test launches, where Korolev presented calculation data on the spacecraft to be sent to the Moon. There was decided to develop three-stage version of R-7 rocket for satellite launches.^[7]

By a Decision of the Council of Ministers of the USSR of January 30, 1956 practical works on the Earth's artificial satellite were approved, it was named "Object D" and planned to be completed in 1957-58, having a mass of 1,000 to 1,400 kg and carrying 200 to 300 kg of scientific instruments.^[8] The first test launch of the "Object D" was scheduled for 1957.^[4] According to that Decision, works on the satellite were divided between institutions as follows:^[9]

• USSR Academy of Sciences was responsible for the general scientific leadership and research instruments supply
• Ministry of Defense Industry and its main executor OKB-1 were assigned a task of creating the satellite as a special carrier for scientific research instruments
• Ministry of Radiotechnical Industry should develop the control system, radiotechnical instruments and the telemetry system
• Ministry of Ship Building Industry should develop gyroscope devices
• Ministry of Machine Building should develop ground launching, refuelling and transportation means
• Ministry of Defence was responsible for conducting launches

[edit] Design

The Sputnik 1 satellite was a 580 mm (23 in) diameter sphere, made of highly polished 2 mm-thick aluminium AMG6T alloy,^[10] carrying four whip-like antennas between 2.4 and 2.9 m in length. The antennas resembled long "whiskers" pointing to one side. It had two radio transmitters (20 and 40 MHz) and is believed to have orbited Earth at a height of about 250 km (150 mi). Analysis of the radio signals was used to gather information about the electron density of the ionosphere. Temperature and pressure were encoded in the duration of radio beeps, which additionally indicated that the satellite had not been punctured by a meteorite. Sputnik 1 was launched by an R-7 rocket. It burned up upon re-entry on 4 January 1958.

Sputnik was the first of several satellites in the Soviet Union's Sputnik program, the majority of which were successful. Sputnik 2, the second satellite to enter orbit, was also the first to carry an animal: the dog Laika. The first failure occurred with Sputnik 3.

[edit] Mission

The designers, engineers and technicians who developed the rocket and satellite were watching the launching at the range.^[11] After the launch they ran to the mobile radio station to listen to signals from the satellite.^[11] They had to wait for some time to ensure that the satellite was in the orbit and made its first circle. The downlink telemetry included data on temperatures inside and on the surface of the sphere.

Already on the first circuit Telegraph Agency of the Soviet Union succeeded to inform: "As result of great, intense work of scientific research institutes and design bureaus the first artificial Earth satellite has been built".^[12] The Sputnik 1 rocket booster also reached Earth orbit and was visible from the ground at night as a first magnitude object. The satellite itself, a small but highly polished sphere, was barely visible at sixth magnitude, and thus more difficult to follow optically. Several replicas of the Sputnik 1 satellite can be seen at museums in Russia and another is on display in the Smithsonian National Air and Space Museum in Washington, D.C.

The actual sequence of decision-making as to the form of Sputnik 1 was convoluted. A tonne-and-a-half, cone-shaped artificial satellite capable of making many physics measurements in space was first planned by Academician Keldysh, but when the Soviets read that the American Project Vanguard had two satellite designs, a small one which was just to see if they could get something into orbit, the Soviets decided to have what translates as the "Simplest Satellite" too, one which was one centimeter larger in diameter, and much heavier, than Vanguard's "real" satellite. They had to see whether the conditions in low Earth orbit would permit the bigger satellite to remain there for a useful length of time. When, months after Sputnik 1, the Vanguard test satellite was orbited, Khrushchev ridiculed it as a "grapefruit." Once the Soviets found they could orbit a test satellite too, they planned to orbit Keldysh's space laboratory satellite as Sputnik 3, and did so after one launch failure.

[edit] Feedback

Further information: Space_Race#Artificial_satellites and Sputnik crisis

“

Our movies and television programs in the fifties were full of the idea of going into space. What came as a surprise was that it was the Soviet Union that launched the first satellite. It is hard to recall the atmosphere of the time. John Logsdon[13]

”

Teams of visual observers 150 stations in the United States and other countries were alerted during the night to watch for the Soviet sphere at dawn and evening twilight. They have been organized in Project Moonwatch to sight the satellite through binoculars or telescopes as it passes overhead.^[14] The USSR asked radio amateurs and commercial stations to record the sound of the satellite on magnetic tape.^[14]

Soviet Union at first agreed to use equipment "compatible" with that of the United States, but then announced the lower frequencies.^[14] The White House declined to comment on military aspects of the launching, but said it "did not come as a surprise."^[15] On October 5 the Naval Research Laboratory announced it had recorded four crossings of Sputnik-1 over the United States.^[14] U.S. President Dwight Eisenhower obtained photographs of the Soviet facilities from Lockheed U-2 flights conducting since 1956.^[16] However everyone on Johnston Island in the Pacific were issued sidearms to carry at all times.^[16]

[edit] Controversy surrounding re-entry

Long-standing official accounts state that, based on the degradation of Sputnik 1's orbit, the satellite re-entered the atmosphere on or about January 4th, 1958, whereupon it is assumed to have burned up completely. The Sputnik 1 rocket booster re-entry was expected to occur somewhere above Alaska, or the West coast of North America, according to Soviet predictions in December 1957. ^[17]

However, in light of recent evidence, certain (primarily structural) components may have survived : Per recent news reports, on the morning of December 8th, 1957, Earl Thomas of Encino, California, was leaving his home to go to work, when he noticed something glowing beneath a tree in his back yard. The source turned out to be several pieces of plastic tubing, which upon investigation, matched structural diagrams of the Sputnik 1 satellite. A local Los Angeles radio DJ, Mark Ford of KDAY Radio, was at the same time offering a $50,000 reward for anyone who had found Sputnik, which reportedly had gone down in the L.A. area. When Thomas tried to claim the reward, he was met by a representative of the United States Air Force, who received the pieces Thomas found, and wrote a receipt on Air Force stationery. Later, after the radio station denied having offered a reward, Thomas brought the receipt back to the Air Force, where the sergeant on duty gave the pieces back to Thomas. The family wrote to government officials at all levels in an attempt to collect the reward, but were told that the government had not offered a reward. Of particular interest, however, was a reply from Colonel W.G. Woodbury of the Air Force, which includes the statement "At the time you recovered the Sputnik parts..." Currently, the disputed parts are in the possession of Bob Morgan, Thomas' son. An exhibit about the parts is currently on display at The Beat Museum, in the North Beach neighborhood of San Francisco.

[edit] Trivia

• The First man made object to reach space was launched over 10 years before Sputnik 1. In 1944, a V2 rocket was launched from Peenemünde on a vertical test shot sub-orbital trajectory to an altitude of 176 kilometers, well beyond the 100 km altitude generally considered to be the border of space (see Kármán line). ^[18]

[edit] Replicas

One Sputnik 1 replica, built by French and Russian teenagers and hand-launched from Mir on November 3, 1997, died after two months in orbit.^[16]

In 2003 a back-up unit of Sputnik 1 called "model PS-1" was sold on eBay (minus the classified military radio parts that were removed in the 1960s). It had been on display in a science institute near Kiev. It is estimated that between four and twenty models were made for testing and other purposes.

A Sputnik 1 model was given as a present to the United Nations and now decorates the entry Hall of its New York City Headquarters.

Another replica is on display at the Smithsonian's National Air and Space Museum

[edit] Notes

[edit] See also

• ILLIAC I - First computer to calculate the orbit of Sputnik I.
• Defense Advanced Research Projects Agency (DARPA, created in 1958)

[edit] External links

[edit] Authentic recordings of the signal

• World's first satellite and the international community's response - contains three authentic recordings of the Sputnik signal, at Voice of Russia

[edit] Primary sources

• Soviet documents
• Newspaper accounts on radio ham operators
• Recording of the radio signal by a German ham radio operator

[edit] Miscellaneous

• 1958 Video Newsreel of Russian Exhibition of Sputnik 1
• NASA on Sputnik 1
• A joint Russian project of Ground microprocessing information systems SRC "PLANETA" and Space Monitoring Information Support laboratory (IKI RAN) dedicated to the 40th anniversary of Sputnik 1

Preceded by None

Sputnik program

Succeeded by Sputnik 2