Sputnik 1 (/ˈspʊtnɪk/ or /ˈspʌtnɪk/; "Satellite-1", or "PS-1", Простейший Спутник-1 or Prosteyshiy Sputnik-1, "Elementary Satellite 1") was the first artificial Earth satellite. The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957, orbiting for three weeks before its batteries died, then silently for two more months before falling back into the atmosphere. It was a 58 cm (23 in) diameter polished metal sphere, with four external radio antennas to broadcast radio pulses. Its radio signal was easily detectable even by radio amateurs, and the 65° inclination and duration of its orbit made its flight path cover virtually the entire inhabited Earth. This surprise success precipitated the American Sputnik crisis and triggered the Space Race, a part of the Cold War. The launch was the beginning of a new era of political, military, technological, and scientific developments.
Tracking and studying Sputnik 1 from Earth provided scientists with valuable information. The density of the upper atmosphere could be deduced from its drag on the orbit, and the propagation of its radio signals gave data about the ionosphere.
Sputnik 1 was launched during the International Geophysical Year from Site No.1/5, at the 5th Tyuratam range, in Kazakh SSR (now known as the Baikonur Cosmodrome). The satellite travelled at about 29,000 kilometres per hour (18,000 mph; 8,100 m/s), taking 96.2 minutes to complete each orbit. It transmitted on 20.005 and 40.002 MHz, which were monitored by radio operators throughout the world. The signals continued for 21 days until the transmitter batteries ran out on 26 October 1957. Sputnik burned up on 4 January 1958 while reentering Earth's atmosphere, after three months, 1440 completed orbits of the Earth, and a distance travelled of about 70 million km (43 million mi).
Replica of Sputnik 1
|Mission type||Technology demonstration|
|Harvard designation||1957 Alpha 2|
|Mission duration||21 days|
Ministry of Radiotechnical Industry
|Launch mass||83.6 kg (184 lb)|
|Dimensions||58 cm (23 in) diameter|
|Start of mission|
|Launch date||4 October 1957, 19:28:34 UTC|
|Launch site||Baikonur 1/5|
|End of mission|
|Last contact||26 October 1957|
|Decay date||4 January 1958|
|Semi-major axis||6,955 km (4,322 mi)|
|Perigee||215 km (134 mi)|
|Apogee||939 km (583 mi)|
|Epoch||4 October 1957, 15:12 UTC|
(20.005 MHz - 40.002 MHz)
On 17 December 1954, chief Soviet rocket scientist Sergei Korolev proposed a developmental plan for an artificial satellite to the Minister of the Defence Industry, Dimitri Ustinov. Korolev forwarded a report by Mikhail Tikhonravov, with an overview of similar projects abroad. Tikhonravov had emphasized that the launch of an orbital satellite was an inevitable stage in the development of rocket technology.
On 29 July 1955, U.S. President Dwight D. Eisenhower announced through his press secretary that, during the International Geophysical Year (IGY), the United States would launch an artificial satellite. A week later, on 8 August, the Politburo of the Communist Party of the Soviet Union approved the proposal to create an artificial satellite. On 30 August Vasily Ryabikov – the head of the State Commission on the R-7 rocket test launches – held a meeting where Korolev presented calculation data for a spaceflight trajectory to the Moon. They decided to develop a three-stage version of the R-7 rocket for satellite launches.
On 30 January 1956 the Council of Ministers approved practical work on an artificial Earth-orbiting satellite. This satellite, named Object D, was planned to be completed in 1957–58; it would have a mass of 1,000 to 1,400 kg (2,200 to 3,100 lb) and would carry 200 to 300 kg (440 to 660 lb) of scientific instruments. The first test launch of "Object D" was scheduled for 1957. Work on the satellite was to be divided among institutions as follows:
Preliminary design work was completed in July 1956 and the scientific tasks to be carried out by the satellite were defined. These included measuring the density of the atmosphere and its ion composition, the solar wind, magnetic fields, and cosmic rays. These data would be valuable in the creation of future artificial satellites. A system of ground stations was to be developed to collect data transmitted by the satellite, observe the satellite's orbit, and transmit commands to the satellite. Because of the limited time frame, observations were planned for only 7 to 10 days and orbit calculations were not expected to be extremely accurate.
By the end of 1956 it became clear that the complexity of the ambitious design meant that 'Object D' could not be launched in time because of difficulties creating scientific instruments and the low specific impulse produced by the completed R-7 engines (304 sec instead of the planned 309 to 310 sec). Consequently, the government rescheduled the launch for April 1958. Object D would later fly as Sputnik 3.
Fearing the U.S. would launch a satellite before the USSR, OKB-1 suggested the creation and launch of a satellite in April–May 1957, before the IGY began in July 1957. The new satellite would be simple, light (100 kg or 220 lb), and easy to construct, forgoing the complex, heavy scientific equipment in favour of a simple radio transmitter. On 15 February 1957 the Council of Ministers of the USSR approved this simple satellite, designated 'Object PS'. This version allowed the satellite to be tracked visually by Earth-based observers, and it could transmit tracking signals to ground-based receiving stations. The launch of two satellites, PS-1 and PS-2, with two R-7 rockets (8K71) was approved, provided that the R-7 completed at least two successful test flights.
The R-7 Semyorka was initially designed as an intercontinental ballistic missile (ICBM) by OKB-1. The decision to build it was made by the Central Committee of the Communist Party of the Soviet Union and the Council of Ministers of the USSR on 20 May 1954. The R-7 was also known by its GRAU (later GURVO the Russian abbreviation for "Chief Directorate of the Rocket Forces") designation 8K71. At the time, the R-7 was known to NATO sources as the T-3 or M-104, and Type A. A special reconnaissance commission selected Tyuratam for the construction of a rocket proving ground, the 5th Tyuratam range, usually referred to as "NIIP-5", or "GIK-5" in the post-Soviet time. The selection was approved on 12 February 1955 by the Council of Ministers of the USSR, but the site would not be completed until 1958. Actual work on the construction of the site began on 20 July by military building units. On 14 June 1956, Sergei Korolev decided to adapt the R-7 rocket to the 'Object D' (Sputnik 3), that would later be replaced by the much lighter 'Object PS' (Sputnik 1).
The first launch of an R-7 rocket (8K71 No.5L) occurred on 15 May 1957. A fire began in the Blok D strap-on almost immediately at liftoff, but the booster continued flying until 98 seconds after launch when the strap-on broke away and the vehicle crashed some 400 km downrange. Three attempts to launch the second rocket (8K71 No.6) were made on 10–11 June, but an assembly defect prevented launch. The unsuccessful launch of the third R-7 rocket (8K71 No.7) took place on 12 July. An electrical short caused the vernier engines to put the missile into an uncontrolled roll which resulted in all of the strap-ons separating 33 seconds into the launch. The R-7 crashed about 7 km from the pad.
The launch of the fourth rocket (8K71 No.8), on 21 August at 15:25 Moscow Time, was successful. The rocket's core boosted the dummy warhead to the target altitude and velocity, reentered the atmosphere, and broke apart at a height of 10 km (6.2 mi) after traveling 6,000 km. On 27 August, the TASS issued a statement on the successful launch of a long-distance multistage ICBM. The launch of the fifth R-7 rocket (8K71 No.9), on 7 September, was also successful, but the dummy was also destroyed on atmospheric re-entry, and hence needed a redesign to completely fulfill its military purpose. The rocket, however, was deemed suitable for satellite launches, and Korolev was able to convince the State Commission to allow the use of the next R-7 to launch PS-1, allowing the delay in the rocket's military exploitation to launch the PS-1 and PS-2 satellites.
On 22 September a modified R-7 rocket, named Sputnik and indexed as 8K71PS, arrived at the proving ground and preparations for the launch of PS-1 began. Compared to the military R-7 test vehicles, the mass of 8K71PS was reduced from 280 tonnes to 272 tonnes; its length with PS-1 was 29.167 metres (95 ft 8.3 in) and the thrust at liftoff was 3.90 MN (880,000 lbf).
PS-1 was not designed to be controlled; it could only be observed. Initial data at the launch site would be collected at six separate observatories and telegraphed to NII-4. Located back in Moscow (at Bolshevo), NII-4 was a scientific research arm of the Ministry of Defence that was dedicated to missile development. The six observatories were clustered around the launch site, with the closest situated 1 km (0.62 mi) from the launch pad.
A second, nationwide observation complex was established to track the satellite after its separation from the rocket. Called the Command-Measurement Complex, it consisted of the coordination center in NII-4 and seven distant stations situated along the line of the satellite's ground track. These tracking stations were located at Tyuratam, Sary-Shagan, Yeniseysk, Klyuchi, Yelizovo, Makat in Guryev Oblast, and Ishkup in Krasnoyarsk Krai. Stations were equipped with radar, optical instruments, and communications systems. Data from stations were transmitted by telegraphs into NII-4 where ballistics specialists calculated orbital parameters.
The observatories used a trajectory measurement system called "Tral", developed by OKB MEI (Moscow Energy Institute), by which they received and monitored data from transponders mounted on the R-7 rocket's core stage. The data was useful even after the satellite's separation from the second stage of the rocket; Sputnik's location was calculated from the data on the second stage's location which followed Sputnik at a known distance. Tracking of the booster during launch had to be accomplished through purely passive means such as visual coverage and radar detection. R-7 test launches demonstrated that the tracking cameras were only good up to an altitude of 200 km (120 mi), but radar could track it for almost 500 km (310 mi).
Outside the Soviet Union, the satellite was tracked by amateur radio operators in many countries. The booster rocket was located and tracked by the British using the Lovell Telescope at the Jodrell Bank Observatory, the only telescope in the world able to do so by radar. Canada's Newbrook Observatory was the first facility in North America to photograph Sputnik 1.
The chief constructor of Sputnik 1 at OKB-1 was Mikhail S. Khomyakov. The satellite was a 585-millimetre (23.0 in) diameter sphere, assembled from two hemispheres that were hermetically sealed with o-rings and connected by 36 bolts. It had a mass of 83.6 kilograms (184 lb). The hemispheres were 2 mm thick, and were covered with a highly polished 1 mm-thick heat shield made of an aluminium–magnesium–titanium alloy, AMG6T. The satellite carried two pairs of antennas designed by the Antenna Laboratory of OKB-1, led by Mikhail V. Krayushkin. Each antenna was made up of two whip-like parts: 2.4 and 2.9 meters (7.9 and 9.5 ft) in length, and had an almost spherical radiation pattern.
The power supply, with a mass of 51 kg (112 lb), was in the shape of an octagonal nut with the radio transmitter in its hole. It consisted of three silver-zinc batteries, developed at the All-Union Research Institute of Power Sources (VNIIT) under the leadership of Nikolai S. Lidorenko. Two of these batteries powered the radio transmitter and one powered the temperature regulation system. The batteries had an expected lifetime of two weeks, and operated for 22 days. The power supply was turned on automatically at the moment of the satellite's separation from the second stage of the rocket.
The satellite had a one-watt, 3.5 kg (7.7 lb) radio transmitting unit inside, developed by Vyacheslav I. Lappo from NII-885, the Moscow Electronics Research Institute, that worked on two frequencies, 20.005 and 40.002 MHz. Signals on the first frequency were transmitted in 0.3 sec pulses (under normal temperature and pressure conditions onboard), with pauses of the same duration filled by pulses on the second frequency. 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. A temperature regulation system contained a fan, a dual thermal switch, and a control thermal switch. If the temperature inside the satellite exceeded 36 °C (97 °F), the fan was turned on; when it fell below 20 °C (68 °F), the fan was turned off by the dual thermal switch. If the temperature exceeded 50 °C (122 °F) or fell below 0 °C (32 °F), another control thermal switch was activated, changing the duration of the radio signal pulses. Sputnik 1 was filled with dry nitrogen, pressurized to 1.3 atm. The satellite had a barometric switch, activated if the pressure inside the satellite fell below 130 kPa, which would have indicated failure of the pressure vessel or puncture by a meteor, and would have changed the duration of radio signal impulse.
While attached to the rocket, Sputnik 1 was protected by a cone-shaped payload fairing, with a height of 80 cm (31.5 in). The fairing separated from both Sputnik and the spent R-7 second stage at the same time as the satellite was ejected. Tests of the satellite were conducted at OKB-1 under the leadership of Oleg G. Ivanovsky.
The control system of the Sputnik rocket was adjusted to an intended orbit of 223 by 1,450 km (139 by 901 mi), with an orbital period of 101.5 min. The trajectory had been calculated earlier by Georgi Grechko, using the USSR Academy of Sciences' mainframe computer.
The Sputnik rocket was launched on 4 October 1957 at 19:28:34 UTC (5 October at the launch site) from Site No.1 at NIIP-5. Telemetry indicated that the strap-ons separated 116 seconds into the flight and the core stage engine shutdown 295.4 seconds into the flight. At shutdown, the 7.5-tonne core stage (with PS-1 attached) had attained an altitude of 223 km (139 mi) above sea level, a velocity of 7,780 m/s (25,500 ft/s), and a velocity vector inclination to the local horizon of 0 degrees 24 minutes. This resulted in an initial orbit of 223 kilometres (139 mi) by 950 kilometres (590 mi), with an apogee approximately 500 kilometres (310 mi) lower than intended, and an inclination of 65.1 degrees and a period of 96.2 minutes.
A fuel regulator in the booster also failed around 16 seconds into launch, which resulted in excessive RP-1 consumption for most of the powered flight and the engine thrust being 4% above nominal. Core stage cutoff was intended for T+296 seconds, but the premature propellant depletion caused thrust termination to occur one second earlier when a sensor detected overspeed of the empty RP-1 turbopump. There were 375 kilograms (827 lb) of LOX remaining at cutoff.
At 19.9 seconds after engine cut-off, PS-1 separated from the second stage and the satellite's transmitter was activated. These signals were detected at the IP-1 station by Junior Engineer-Lieutenant V.G. Borisov, where reception of Sputnik 1's "beep-beep-beep" tones confirmed the satellite's successful deployment. Reception lasted for two minutes, until PS-1 fell below the horizon. The Tral telemetry system on the R-7 core stage continued to transmit and was detected on its second orbit.
The designers, engineers and technicians who developed the rocket and satellite watched the launch from the range. After the launch they drove to the mobile radio station to listen for signals from the satellite. They waited about 90 minutes to ensure that the satellite had made one orbit and was transmitting before Korolev called Soviet premier Nikita Khrushchev.
On the first orbit the Telegraph Agency of the Soviet Union (TASS) transmitted: "As result of great, intense work of scientific institutes and design bureaus the first artificial Earth satellite has been built." The R-7 core stage, with a mass of 7.5 tonnes and a length of 26 meters, also reached Earth orbit. It was a first magnitude object following behind the satellite and visible at night. Deployable reflective panels were placed on the booster in order to increase its visibility for tracking. A small highly polished sphere, the satellite was barely visible at sixth magnitude, and thus harder to follow optically. The batteries ran out on 26 October 1957, after the satellite completed 326 orbits.
The core stage of the R-7 remained in orbit for two months until 2 December 1957, while Sputnik 1 orbited for three months, until 4 January 1958, having completed 1,440 orbits of the Earth.
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.
The Soviets provided details of Sputnik 1 before the launch, but few outside the Soviet Union noticed. After reviewing information publicly available before the launch, the science writer Willy Ley wrote in 1958:
If somebody tells me that he has the rockets to shoot — which we know from other sources, anyway — and tells me what he will shoot, how he will shoot it, and in general says virtually everything except for the precise date — well, what should I feel like if I'm surprised when the man shoots?
Organized through the citizen science project Operation Moonwatch, teams of visual observers at 150 stations in the United States and other countries were alerted during the night to watch for the satellite at dawn and during the evening twilight as it passed overhead. The USSR requested amateur and professional radio operators to tape record the signal being transmitted from the satellite.
News reports at the time pointed out that "anyone possessing a short wave receiver can hear the new Russian earth satellite as it hurtles over this area of the globe." Directions, provided by the American Radio Relay League were to "Tune in 20 megacycles sharply, by the time signals, given on that frequency. Then tune to slightly higher frequencies. The 'beep, beep' sound of the satellite can be heard each time it rounds the globe." The first recording of Sputnik 1's signal was made by RCA engineers near Riverhead, Long Island. They then drove the tape recording into Manhattan for broadcast to the public over NBC radio. However, as Sputnik rose higher over the East Coast, its signal was picked up by W2AEE, the ham radio station of Columbia University. Students working in the university's FM station, WKCR, made a tape of this, and were the first to rebroadcast the Sputnik signal to the American public (or whoever could receive the FM station).
The Soviet Union agreed transmit on frequencies that worked with the United States' existing infrastructure, but later announced the lower frequencies. Asserting that the launch "did not come as a surprise", the White House refused to comment on any military aspects. On 5 October the Naval Research Laboratory captured recordings of Sputnik 1 during four crossings over the United States. The USAF Cambridge Research Center collaborated with Bendix-Friez, Westinghouse Broadcasting Co., and the Smithsonian Astrophysical Observatory to obtain a video of Sputnik's rocket body crossing the pre-dawn sky of Baltimore, broadcast on 12 October by WBZ-TV in Boston.
The success of Sputnik 1 seemed to have changed minds around the world regarding a shift in power to the Soviets.
In Britain, the media and population initially reacted with a mixture of fear for the future, but also amazement about humankind's progress. Many newspapers and magazines heralded the arrival of the Space Age. However, when the Soviet Union launched a second craft, containing the dog Laika, the media narrative returned to one of anti-communism and many people sent protests to the Russian embassy and the RSPCA.
Sputnik 1 was not immediately used for Soviet propaganda. The Soviets had kept quiet about their earlier accomplishments in rocketry, fearing that it would lead to secrets being revealed and failures being exploited by the West. When the Soviets began using Sputnik in their propaganda, they emphasized pride in the achievement of Soviet technology, arguing that it demonstrated the Soviets' superiority over the West. People were encouraged to listen to Sputnik's signals on the radio and to look out for Sputnik in the night sky. While Sputnik itself had been highly polished, its small size made it barely visible to the naked eye. What most watchers actually saw was the much more visible 26-metre core stage of the R-7. Shortly after the launch of PS-1, Khrushchev pressed Korolev to launch another satellite to coincide with the 40th anniversary of the October Revolution, on 7 November 1957.
The launch of Sputnik 1 surprised the American public and shattered the perception, furthered by American propaganda, of the United States as the technological superpower and the Soviet Union as a backward country. Privately, however, the CIA and President Eisenhower were aware of progress being made by the Soviets on Sputnik from secret spy plane imagery. Together with the Jet Propulsion Laboratory (JPL), the Army Ballistic Missile Agency built Explorer 1, and launched it on 31 January 1958. Before work was completed, however, the Soviet Union launched a second satellite, Sputnik 2, on 3 November 1957. Meanwhile, the televised failure of Vanguard TV3 on 6 December 1957 deepened American dismay over the country's position in the Space Race. The Americans took a more aggressive stance in the emerging space race, resulting in an emphasis on science and technological research, and reforms in many areas from the military to education systems. The federal government began investing in science, engineering, and mathematics at all levels of education. An advanced research group was assembled for military purposes. These research groups developed weapons such as ICBMs and missile defense systems, as well as spy satellites for the U.S.
On Friday, 4 October 1957, the Soviets had orbited the world's first artificial satellite. Anyone who doubted its existence could walk into the backyard just after sunset and see it.— Mike Gray, Angle of Attack
Initially, U.S. President Eisenhower was not surprised by Sputnik 1. He had been forewarned of the R-7's capabilities by information derived from U-2 spy plane overflight photos, as well as signals and telemetry intercepts. The Eisenhower administration's first response was low-key and almost dismissive. Eisenhower was even pleased that the USSR, not the U.S., would be the first to test the waters of the still-uncertain legal status of orbital satellite overflights. Eisenhower had suffered the Soviet protests and shoot-downs of Project Genetrix (Moby Dick) balloons and was concerned about the probability of a U-2 being shot down. To set a precedent for "freedom of space" before the launch of America's secret WS-117L spy satellites, the U.S. had launched Project Vanguard as its own "civilian" satellite entry for the International Geophysical Year. Eisenhower greatly underestimated the reaction of the American public, who were shocked by the launch of Sputnik and by the televised failure of the Vanguard Test Vehicle 3 launch attempt. The sense of fear was inflamed by Democratic politicians and professional cold warriors, who portrayed the United States as woefully behind. One of the many books that suddenly appeared for the lay-audience noted seven points of "impact" upon the nation: Western leadership, Western strategy and tactics, missile production, applied research, basic research, education, and democratic culture.
The U.S. soon had a number of successful satellites, including Explorer 1, Project SCORE, and Courier 1B. However, public reaction to the Sputnik crisis spurred America to action in the Space Race, leading to the creation of both the Advanced Research Projects Agency (renamed the Defense Advanced Research Projects Agency, or DARPA, in 1972), and NASA (through the National Aeronautics and Space Act), as well as increased U.S. government spending on scientific research and education through the National Defense Education Act.
Sputnik also contributed directly to a new emphasis on science and technology in American schools. With a sense of urgency, Congress enacted the 1958 National Defense Education Act, which provided low-interest loans for college tuition to students majoring in math and science. After the launch of Sputnik, a poll conducted and published by the University of Michigan showed that 26% of Americans surveyed thought that Russian sciences and engineering were superior to that of the United States. (A year later, however, that figure had dropped to 10% as the U.S. began launching its own satellites into space.)
Sputnik also inspired a generation of engineers and scientists. Harrison Storms, the North American designer who was responsible for the X-15 rocket plane, and went on to head the effort to design the Apollo Command/Service Module and Saturn V launch vehicle's second stage was moved by the launch of Sputnik to think of space as being the next step for America. Astronauts Alan Shepard (who was the first American in space) and Deke Slayton later wrote of how the sight of Sputnik 1 passing overhead inspired them to their new careers.
The launch of Sputnik 1 led to the resurgence of the suffix -nik in the English language. The American writer Herb Caen was inspired to coin the term "beatnik" in an article about the Beat Generation in the San Francisco Chronicle on 2 April 1958.
At least two vintage duplicates of Sputnik 1 exist, built apparently as backup units. One resides just outside Moscow in the corporate museum of Energia, the modern descendant of Korolev's design bureau, where it is on display by appointment only. Another is in the Museum of Flight in Seattle, Washington. Unlike Energia's unit, it has no internal components, but it does have casings and molded fittings inside (as well as evidence of battery wear), which suggest it was built as more than just a model. Authenticated by the Memorial Museum of Cosmonautics in Moscow, the unit was auctioned in 2001 and purchased by an anonymous private buyer, who donated it to the museum. Two more Sputnik backups are said to be in the personal collections of American entrepreneurs Richard Garriott and Jay S. Walker.
In 1959, the Soviet Union donated a replica of Sputnik to the United Nations. There are other full-size Sputnik replicas (with varying degrees of accuracy) on display in locations around the world, including the National Air and Space Museum in the US, the Science Museum in England, the Powerhouse Museum in Australia, and outside the Russian embassy in Spain.
Three one-third scale student-built replicas of Sputnik 1 were deployed from the Mir space station between 1997 and 1999. The first, named Sputnik 40 to commemorate the fortieth anniversary of the launch of Sputnik 1, was deployed in November 1997. Sputnik 41 was launched a year later, and Sputnik 99 was deployed in February 1999. A fourth replica was launched, but never deployed, and was destroyed when Mir was deorbited.
Dongfanghong (Chinese: 东方红; pinyin: Dōngfāng Hóng; literally: 'The East is Red') was a satellite program of the People's Republic of China. The program started in August 1965 as Project 651—a less ambitious successor to the earlier Project 581—with the goal of launching a satellite heavier than both Sputnik 1 and Explorer 1 into space, and developing all the necessary technologies to do so.Earth observation satellite
An Earth observation satellite or Earth remote sensing satellite is satellite specifically designed for Earth observation from orbit, similar to spy satellites but intended for non-military uses such as environmental monitoring, meteorology, map making etc.
The first occurrence of satellite remote sensing can be dated to the launch of the first artificial satellite, Sputnik 1, by the Soviet Union on October 4, 1957. Sputnik 1 sent back radio signals, which scientists used to study the ionosphere.
NASA launched the first American satellite, Explorer 1, in January 31, 1958. The information sent back from its radiation detector led to the discovery of the Earth's Van Allen radiation belts.
The TIROS-1 spacecraft, launched on April 1, 1960 as part of NASA's TIROS (Television Infrared Observation Satellite) Program, sent back the first television footage of weather patterns to be taken from space.
As of 2008, more than 150 Earth observation satellites were in orbit, recording data with both passive and active sensors and acquiring more than 10 terabits of data daily.Most Earth observation satellites carry instruments that should be operated at a relatively low altitude. Altitudes below 500-600 kilometers are in general avoided, though, because of the significant air-drag at such low altitudes making frequent orbit reboost maneuvres necessary. The Earth observation satellites ERS-1, ERS-2 and Envisat of European Space Agency as well as the MetOp spacecraft of EUMETSAT are all operated at altitudes of about 800 km. The Proba-1, Proba-2 and SMOS spacecraft of European Space Agency are observing the Earth from an altitude of about 700 km. The Earth observation satellites of UAE, DubaiSat-1 & DubaiSat-2 are also placed in Low Earth Orbits (LEO) orbits and providing satellite imagery of various parts of the Earth.To get (nearly) global coverage with a low orbit it must be a polar orbit or nearly so. A low orbit will have an orbital period of roughly 100 minutes and the Earth will rotate around its polar axis with about 25 deg between successive orbits, with the result that the ground track is shifted towards west with these 25 deg in longitude. Most are in sun-synchronous orbits.
Spacecraft carrying instruments for which an altitude of 36000 km is suitable sometimes use a geostationary orbit. Such an orbit allows uninterrupted coverage of more than 1/3 of the Earth. Three geostationary spacecraft at longitudes separated with 120 deg can cover the whole Earth except the extreme polar regions. This type of orbit is mainly used for meteorological satellites.Explorer 2
Explorer 2 was to be a repeat of the Explorer 1 mission. However, due to a failure in the rocket during launch, the spacecraft did not reach orbit.
Explorer 2 was launched from Cape Canaveral Air Force Station LC-26A in Florida on March 5, 1958 at 18:28 UTC, by a Juno-I launch vehicle.
The Juno-I had its origins in the United States Army's Project Orbiter in 1954. The project was canceled in 1955, when the decision was made to proceed with Project Vanguard.
Following the launch of the Soviet Sputnik 1 on October 4, 1957, the Army Ballistic Missile Agency (ABMA) was directed to proceed with the launching of a satellite using the Juno-I four-stage variant of the three-stage Jupiter-C, which had already been flight-tested in nose-cone re-entry tests for the Jupiter IRBM (intermediate-range ballistic missile). Working closely together, ABMA and Jet Propulsion Laboratory (JPL) completed the job of modifying the Jupiter-C and building Explorer 1 in 84 days.International Designator
The International Designator, also known as COSPAR designation, and in the United States as NSSDC ID, is an international naming convention for satellites. It consists of the launch year, a 3-digit incrementing launch number of that year and up to a 3-letter code representing the sequential identifier of a piece in a launch.
For example, 1990-037A is the Space Shuttle Discovery on mission STS-31, which carried the Hubble Space Telescope (1990-037B) into space. This launch was the 37th known successful launch worldwide in 1990. The number reveals that it was launched in 1990 and that it was the 37th launch made that year. Spacecraft which do not complete an orbit of the Earth, for example launches which fail to achieve orbit, are not usually assigned IDs.The designation system has been generally known as the COSPAR system, named for the Committee on Space Research (COSPAR) of the International Council for Science.
COSPAR subsumed the first designation system, devised at Harvard University in 1958. That system used letters of the Greek alphabet to designate artificial satellites. For example, Sputnik 1 was designated 1957 Alpha 2. The Harvard designation system continued to be used for satellites launched up to the end of 1962, when it was replaced with the modern system. The first satellite to receive a new-format designator was Luna E-6 No.2, 1963-001B, although some sources, including the NSSDC website, anachronistically apply the new-format designators to older satellites, even those no longer in orbit at the time of its introduction.
The catalog is administered in the United States by the National Space Science Data Center (NSSDC), part of NASA.Korabl-Sputnik 1
Korabl-Sputnik 1 (Russian: Корабль Спутник 1 meaning Vessel Satellite 1), also known as Sputnik 4 in the West, was the first test flight of the Soviet Vostok programme, and the first Vostok spacecraft. It was launched on May 15, 1960. Though Korabl-Sputnik 1 was unmanned, it was a precursor to the first human spaceflight, Vostok 1. Its weight was 4,540 kilograms (10,010 lb), of which 1,477 kilograms (3,256 lb) was instrumentation. A bug in the guidance system had pointed the capsule in the wrong direction, so instead of dropping into the atmosphere the satellite moved into a higher orbit. The descent module re-entered the atmosphere on September 1, 1962. A piece was found in the middle of North 8th Street in Manitowoc, Wisconsin in the northern United States.
This spacecraft, the first of a series of spacecraft used to investigate the means for manned space flight, contained scientific instruments, a television system, and a self-sustaining biological cabin with a dummy of a man. The spacecraft was designed to study the operation of the life support system and the stresses of flight. The spacecraft radioed both extensive telemetry and prerecorded voice communications. After four days of flight, the retro rocket was fired and the descent module was separated from its equipment module, but because of an incorrect attitude the spacecraft did not reenter the atmosphere as planned. The descent module re-entered the atmosphere on September 5, 1962, while the equipment module re-entered on October 15, 1965.Giovanni Battista Judica Cordiglia, who set up his own amateur listening station at Torre Bert near Turin, is reported to have claimed that radio signals were received on November 28, 1960 which could have originated from this spacecraft; the spacecraft is known to have radioed prerecorded voice communications. It has led some to believe a conspiracy theory that the spacecraft may have been manned by the Lost Cosmonauts.List of spacecraft called Sputnik
Sputnik (Спутник, Russian for "satellite" or "fellow traveler") is a spacecraft launched under the Soviet space program. "Sputnik 1", "Sputnik 2" and "Sputnik 3" were the official Soviet names of those objects, while the remaining designations in the series ("Sputnik 4" and so on) were not official names, but were names applied in the West, to objects whose original Soviet names may not have been known at the time.Newbrook
Newbrook is a hamlet in central Alberta, Canada within Thorhild County. It is located at the junction of Highway 63 and Highway 661, approximately 28 kilometres (17 mi) northeast of Thorhild and 36 kilometres (22 mi) south of Boyle. It has an elevation of 665 metres (2,182 ft).
The hamlet is located in census division No. 13 and in the federal riding of Westlock-St. Paul.
The hamlet and surrounding area has a strong Polish and Ukrainian influence, mostly from immigration at the turn of the 20th century. The former Newbrook Observatory, a meteor observatory that was the first facility in North America to photograph Sputnik 1, is located in the hamlet.Project Vanguard
Project Vanguard was a program managed by the United States Naval Research Laboratory (NRL), which intended to launch the first artificial satellite into Earth orbit using a Vanguard rocket as the launch vehicle from Cape Canaveral Missile Annex, Florida.
In response to the surprise launch of Sputnik 1 on October 4, 1957, the U.S. restarted the Explorer program, which had been proposed earlier by the Army Ballistic Missile Agency (ABMA). Privately, however, the CIA and President Dwight D. Eisenhower were aware of progress being made by the Soviets on Sputnik from secret spy plane imagery. Together with the Jet Propulsion Laboratory (JPL), ABMA built Explorer 1 and launched it on January 31, 1958. Before work was completed, however, the Soviet Union launched a second satellite, Sputnik 2, on November 3, 1957. Meanwhile, the spectacular televised failure of Vanguard TV3 on December 6, 1957 deepened American dismay over the country's position in the Space Race.
On March 17, 1958, Vanguard 1 became the second artificial satellite successfully placed in Earth orbit by the United States. It was the first solar-powered satellite. Just 152 mm (6.0 in) in diameter and weighing just 1.4 kg (3.1 lb), Vanguard 1 was described by then-Soviet Premier Nikita Khrushchev as, "The grapefruit satellite."Vanguard 1, and the upper stage of its launch rocket, are the oldest artificial satellites still in space, as Vanguard's predecessors, Sputnik 1, Sputnik 2, and Explorer 1, have decayed from orbit.Satellite
In the context of spaceflight, a satellite is an object that has been intentionally placed into orbit. These objects are called artificial satellites to distinguish them from natural satellites such as Earth's Moon.
On 4 October 1957 the Soviet Union launched the world's first artificial satellite, Sputnik 1. Since then, about 8,100 satellites from more than 40 countries have been launched. According to a 2018 estimate, some 4,900 remain in orbit, of those about 1,900 were operational; while the rest have lived out their useful lives and become space debris. Approximately 500 operational satellites are in low-Earth orbit, 50 are in medium-Earth orbit (at 20,000 km), and the rest are in geostationary orbit (at 36,000 km). A few large satellites have been launched in parts and assembled in orbit. Over a dozen space probes have been placed into orbit around other bodies and become artificial satellites to the Moon, Mercury, Venus, Mars, Jupiter, Saturn, a few asteroids, a comet and the Sun.
Satellites are used for many purposes. Among several other applications, they can be used to make star maps and maps of planetary surfaces, and also take pictures of planets they are launched into. Common types include military and civilian Earth observation satellites, communications satellites, navigation satellites, weather satellites, and space telescopes. Space stations and human spacecraft in orbit are also satellites. Satellite orbits vary greatly, depending on the purpose of the satellite, and are classified in a number of ways. Well-known (overlapping) classes include low Earth orbit, polar orbit, and geostationary orbit.
A launch vehicle is a rocket that places a satellite into orbit. Usually, it lifts off from a launch pad on land. Some are launched at sea from a submarine or a mobile maritime platform, or aboard a plane (see air launch to orbit).
Satellites are usually semi-independent computer-controlled systems. Satellite subsystems attend many tasks, such as power generation, thermal control, telemetry, attitude control and orbit control.Satellite Catalog Number
The Satellite Catalog Number (also known as NORAD Catalog Number, NORAD ID, NASA catalog number, USSPACECOM object number or simply catalog number and similar variants) is a sequential 5-digit number assigned by USSPACECOM (United States Space Command) to all Earth orbiting satellites in order of identification. Before USSPACECOM, the catalog was maintained by NORAD. The first catalogued object, catalog number 00001, is the Sputnik 1 launch vehicle, with the Sputnik 1 satellite assigned catalog number 00002.As of August 2017, the National Space Science Data Center Master Catalog listed more than 42,900 tracked objects including more than 7,800 satellites launched into orbit since 1957.Space Age
The Space Age is a time period encompassing the activities related to the Space Race, space exploration, space technology, and the cultural developments influenced by these events. The Space Age is generally considered to have begun with Sputnik 1 in 1957.Sputnik (rocket)
The Sputnik rocket was an unmanned orbital carrier rocket designed by Sergei Korolev in the Soviet Union, derived from the R-7 Semyorka ICBM. On 4 October 1957, it was used to perform the world's first satellite launch, placing Sputnik 1 into a low Earth orbit.
Two versions of the Sputnik were built, the Sputnik-PS (GRAU index 8K71PS), which was used to launch Sputnik 1 and later Sputnik 2, and the Sputnik (8A91), which failed to launch a satellite in April 1958, and subsequently launched 3 on 15 May 1958.A later member of the R-7 family, the Polyot, used the same configuration as the Sputnik rocket, but was constructed from Voskhod components. Because of the similarity, the Polyot was sometimes known as the Sputnik 11A59.Sputnik 2
Sputnik 2 (Russian pronunciation: [ˈsputʲnʲɪk], Russian: Спутник-2, Satellite 2), or Prosteyshiy Sputnik 2 (PS-2, Russian: Простейший Спутник 2, Elementary Satellite 2) was the second spacecraft launched into Earth orbit, on 3 November 1957, and the first to carry a living animal, a Soviet space dog named Laika. Laika survived for several orbits but died a few hours after the launch.Launched by the U.S.S.R., Sputnik 2 was a 4-meter (13 foot) high cone-shaped capsule with a base diameter of 2 meters (6.6 feet) that weighed around 500 kg, though it was not designed to separate from the rocket core that brought it to orbit, bringing the total mass in orbit to 89 kilos. It contained several compartments for radio transmitters, a telemetry system, a programming unit, a regeneration and temperature-control system for the cabin, and scientific instruments. A separate sealed cabin contained the dog Laika.
Engineering and biological data were transmitted using the Tral D telemetry system, transmitting data to Earth for a 15-minute period during each orbit. Two photometers were on board for measuring solar radiation (ultraviolet and x-ray emissions) and cosmic rays. A 100 line television camera provided images of Laika.
Sputnik 2 was launched into space only 32 days after its predecessor Sputnik 1. Due to the huge success of Sputnik 1, Nikita Khrushchev ordered Sergey Korolev back to work creating a Sputnik 2 that needed to be ready for space for the 40th anniversary of the Bolshevik revolution.The plan for Sputnik 1 and Sputnik 2 was initiated and presented by Korolev, and was approved in January 1957. At that time, it was not clear that the Soviets' main satellite plan (which would eventually become Sputnik 3) would be able to get to space because of the ongoing issues with the R-7 ICBM, which would be needed to launch a satellite of that size. “Korolev proposed substituting two 'simple satellites' for the IGY satellite”. The choice to launch these two instead of waiting for the more advanced Sputnik 3 to be finished was largely motivated by the desire to launch a satellite to orbit before the US.Sputnik 40
Sputnik 40 (Russian: Спутник 40, French: Spoutnik 40), also known as Sputnik Jr, PS-2 and Radio Sputnik 17 (RS-17), was a Franco-Russian amateur radio satellite which was launched in 1997 to commemorate the fortieth anniversary of the launch of Sputnik 1, the world's first artificial satellite. A 4-kilogram (8.8 lb) one-third scale model of Sputnik 1, Sputnik 40 was deployed from the Mir space station on 3 November 1997. Built by students, the spacecraft was constructed at the Polytechnic Laboratory of Nalchik in Kabardino-Balkaria, whilst its transmitter was assembled by Jules Reydellet College in Réunion with technical support from AMSAT-France.Sputnik 41
Sputnik 41 (Russian: Спутник 41, French: Spoutnik 41), also known as Sputnik Jr 2 and Radio Sputnik 18 (RS-18), was a Franco-Russian amateur radio satellite which was launched in 1998 to commemorate the hundredth anniversary of the Aéro-Club de France, and the forty-first anniversary of the launch of Sputnik 1, the world's first artificial satellite. A 4-kilogram (8.8 lb) one-third scale model of Sputnik 1, Sputnik 41 was deployed from the Mir space station on 10 November 1998.Sputnik 41 was launched aboard Progress M-40 at 04:14 UTC on 25 October 1998, along with supplies for Mir and the Znamya-2.5 reflector experiment. A Soyuz-U carrier rocket placed the spacecraft into orbit, flying from Site 1/5 at the Baikonur Cosmodrome in Kazakhstan: the same launch pad used by Sputnik 1. Progress M-40 docked to Mir on 27 October, and the satellite was transferred to the space station. At about 19:30 UTC on 10 November, during an extra-vehicular activity, Sputnik 41 was deployed by cosmonauts Gennady Padalka and Sergei Avdeyev.On 24 November, a fortnight after deployment, Sputnik 41 was in a low Earth orbit with a perigee of 339 kilometres (211 mi), an apogee of 352 kilometres (219 mi), an inclination of 51.6 degrees, and a period of 91.44 minutes. The satellite was given the International Designator 1998-062C, and was catalogued by the United States Space Command as 25533. Having ceased operations on 11 December 1998 after its batteries expired, Sputnik 41 decayed from orbit on 11 January 1999.Sputnik 41 was originally intended to be built aboard Mir, based on a satellite launched in October 1997 as a backup for Sputnik 40. That spacecraft had been stored aboard the space station for a year after the successful deployment of Sputnik 40, and it was intended that it would be fitted with upgraded electronics and deployed. By the time of launch, the project had grown to involve a complete satellite, and the Sputnik 40 backup was never deployed.Sputnik crisis
The Sputnik crisis was a period of public fear and anxiety in Western nations about the perceived technological gap between the United States and Soviet Union caused by the Soviets' launch of Sputnik 1, the world's first artificial satellite. The crisis was a key event in the Cold War that triggered the creation of NASA and the Space Race between the two superpowers. The satellite was launched on October 4, 1957, from the Baikonur Cosmodrome.Vostok-L
The Vostok-L (Russian: Восток meaning "East"), GRAU index 8K72 was a rocket used by the Soviet Union to conduct several early tests of the Vostok spacecraft. It was derived from the Luna rocket, with a slightly enlarged second stage to accommodate the larger payload, and was a member of the Vostok family of rockets. It used the new 8K74 core instead of the 8K71 used on the original R-7 ICBM and the Luna boosters. The 8K74, first tested in December 1959, had a number of technical improvements to increase reliability and make servicing easier. Four launches were conducted between 15 May and 1 December 1960, three of which successfully reached orbit.
The first flight, on 15 May 1960, carried the Korabl'-Sputnik 1 spacecraft. The second launched on 28 July, however one of the booster engines burned through at launch, causing the booster to separate prematurely, 19 seconds after launch. The rocket broke up 30 seconds after liftoff, killing the two dogs that were aboard the spacecraft. The third flight successfully placed Korabl'-Sputnik 2 into orbit on 19 August, whilst the fourth and final flight orbited Korabl'-Sputnik 3 on 1 December. The Vostok-L was replaced by an uprated version, the Vostok-K, which offered a greater payload capacity.Vostok (rocket family)
Vostok (Russian: Восток, translated as "East") was a family of rockets derived from the Soviet R-7 Semyorka ICBM and was designed for the human spaceflight programme. This family of rockets launched the first artificial satellite (Sputnik 1) and the first manned spacecraft (Vostok) in human history. It was a subset of the R-7 family of rockets.
On March 18, 1980 a Vostok-2M rocket exploded on its launch pad at Plesetsk during a fueling operation, killing 48 people. An investigation into a similar – but avoided – accident revealed that the substitution of lead-based for tin-based solder in hydrogen peroxide filters allowed the breakdown of the H2O2, thus causing the resultant explosion.Yubileiny
Yubileiny (Russian: Юбиле́йный, lit. Jubilee) is an educational Russian satellite built by NPO PM to commemorate the 50th anniversary of the launch of Sputnik 1, the first artificial satellite to be placed into Earth orbit. The satellite was launched on 23 May 2008 aboard a Rokot class rocket from the LC-133 launch facility at the Plesetsk Cosmodrome, after being delayed since the end of 2007. It was a secondary payload accompanying a cluster of three Gonets communication satellites, and utilised the excess capacity of the carrier.The satellite mission was to broadcast audio and video about the Soviet and Russian space programmes, as well as to imitate the beeping call signals of Sputnik 1. These signals are intended for being receipted by amateur radio enthusiasts.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets.