78-534: The Lunar Orbiter program was a series of five uncrewed lunar orbiter missions launched by the United States in 1966 and 1967. Intended to help select Apollo landing sites by mapping the Moon's surface, they provided the first photographs from lunar orbit and photographed both the Moon and Earth. All five missions were successful, and 99 percent of the lunar surface was mapped from photographs taken with
156-785: A satellite radio and mobile TV standard which, as with proprietary systems in the United States, is incompatible with the open standards used in the rest of the world. In May 2009, Inmarsat and Solaris Mobile (a joint venture between Eutelsat and SES ( EchoStar Mobile )) were each awarded a 2×15 MHz portion of the S band by the European Commission . The two companies are allowed two years to start providing pan-European MSS services for 18 years. Allocated frequencies are 1.98 to 2.01 GHz for Earth to space communications, and from 2.17 to 2.2 GHz for space to Earth communications. The Eutelsat W2A satellite
234-487: A wireless router to connect them to the Internet, and in wireless access points in public places like coffee shops, hotels, libraries and airports to provide the public Internet access for mobile devices. Mobile services are operated in the 2.3 GHz to 2.6 GHz range, specifically between the 2300 - 2400 MHz band and the 2500 - 2690 MHz band. Spectrum in the 3.55 - 3.7 GHz band has been auctioned off in
312-458: A 10 W transmitter and the directional one-meter diameter high-gain antenna for transmission of photographs, and a 0.5 W transmitter and omnidirectional low-gain antenna for other communications. Both transmitters operated in the S band at about 2295 MHz. Thermal control was maintained by a multilayer aluminized Mylar and Dacron thermal blanket which enshrouded the main bus, special paint, insulation, and small heaters. Originally,
390-588: A 58-centimeter (23 in) sphere which weighed 83.6 kilograms (184 lb). Explorer 1 carried sensors which confirmed the existence of the Van Allen belts, a major scientific discovery at the time, while Sputnik 1 carried no scientific sensors. On 17 March 1958, the US orbited its second satellite, Vanguard 1 , which was about the size of a grapefruit, and which remains in a 670-by-3,850-kilometre (360 by 2,080 nmi) orbit as of 2016 . The first attempted lunar probe
468-613: A 610 mm F 5.6 Panoramic lens manufactured by the Pacific Optical Company. The cameras exposed negatives on 65 mm Kodak Bimat film, which was then developed onboard using a semidry process. The subsystem's photomultiplier then scanned the images by a for transmission to Earth as analog video . The receiving stations on Earth then transferred the video images back onto film, which was then shipped to Kodak in Rochester for final processing and printing. This system
546-486: A change which provided vastly improved resolution over the original images released in the 1960s. The first of these restored images were released in late 2008. Almost all of the Lunar Orbiter images had been successfully recovered As of February 2014 and were undergoing digital processing before being submitted to NASA's Planetary Data System . The above links lead to a whole book on the Lunar Orbiter program. For
624-535: A considerable amount of time, is to follow a trajectory on the Interplanetary Transport Network . A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Space telescopes avoid the filtering and distortion of electromagnetic radiation which they observe, and avoid light pollution which ground-based observatories encounter. They are divided into two types: satellites which map
702-549: A descent through that atmosphere towards an intended/targeted region of scientific value, and a safe landing that guarantees the integrity of the instrumentation on the craft is preserved. While the robotic spacecraft is going through those parts, it must also be capable of estimating its position compared to the surface in order to ensure reliable control of itself and its ability to maneuver well. The robotic spacecraft must also efficiently perform hazard assessment and trajectory adjustments in real time to avoid hazards. To achieve this,
780-510: A film handling apparatus. Both lenses, a 610 mm (24 in) narrow angle high resolution (HR) lens and an 80 mm (3.1 in) wide angle medium resolution (MR) lens, placed their frame exposures on a single roll of 70 mm film . The axes of the two cameras were coincident so the area imaged in the HR frames were centered within the MR frame areas. The film was moved during exposure to compensate for
858-429: A high gain antenna on a 1.32 m (4 ft 4 in) boom and a low-gain antenna on a 2.08 m (6 ft 10 in) boom. Above the equipment deck, the middle deck held the velocity control engine, propellant, oxidizer, and pressurization tanks, Sun sensors, and micrometeoroid detectors. The third deck consisted of a heat shield to protect the spacecraft from the firing of the velocity control engine. The nozzle of
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#1732772544401936-433: A positively charged atom. The positively charged ions are guided to pass through positively charged grids that contains thousands of precise aligned holes are running at high voltages. Then, the aligned positively charged ions accelerates through a negative charged accelerator grid that further increases the speed of the ions up to 40 kilometres per second (90,000 mph). The momentum of these positively charged ions provides
1014-421: A resolution of 60 meters (200 ft) or better. The first three missions were dedicated to imaging 20 potential crewed lunar landing sites, selected based on Earth-based observations. These were flown at low-inclination orbits. The fourth and fifth missions were devoted to broader scientific objectives and were flown in high-altitude polar orbits. Lunar Orbiter 4 photographed the entire nearside and nine percent of
1092-587: Is 2.4 GHz IEEE 802.11 Wi-Fi wireless networks, allowing smartphones, laptops, printers and TVs to connect to the internet without cables. The largest use of this band is by Wi-Fi networks; the IEEE 802.11b and 802.11g standards use the 2.4 GHz section of the S band. These are the most widely used computer networks in the world, used globally in home and small office networks to link desktop and laptop computers, tablet computers , smartphones , smart TVs , printers , and smart speakers together and to
1170-625: Is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the conventional boundary between the UHF and SHF bands at 3.0 GHz. The S band is used by airport surveillance radar for air traffic control , weather radar , surface ship radar , and some communications satellites , particularly satellites used by NASA to communicate with
1248-441: Is increased fuel consumption or it is a physical hazard such as a poor landing spot in a crater or cliff side that would make landing very not ideal (hazard assessment). In planetary exploration missions involving robotic spacecraft, there are three key parts in the processes of landing on the surface of the planet to ensure a safe and successful landing. This process includes an entry into the planetary gravity field and atmosphere,
1326-457: Is not one universally used propulsion system: monopropellant, bipropellant, ion propulsion, etc. Each propulsion system generates thrust in slightly different ways with each system having its own advantages and disadvantages. But, most spacecraft propulsion today is based on rocket engines. The general idea behind rocket engines is that when an oxidizer meets the fuel source, there is explosive release of energy and heat at high speeds, which propels
1404-475: Is often called a space probe or space observatory . Many space missions are more suited to telerobotic rather than crewed operation, due to lower cost and risk factors. In addition, some planetary destinations such as Venus or the vicinity of Jupiter are too hostile for human survival, given current technology. Outer planets such as Saturn , Uranus , and Neptune are too distant to reach with current crewed spaceflight technology, so telerobotic probes are
1482-419: Is the same as that of monopropellant propulsion system: very dangerous to manufacture, store, and transport. An ion propulsion system is a type of engine that generates thrust by the means of electron bombardment or the acceleration of ions. By shooting high-energy electrons to a propellant atom (neutrally charge), it removes electrons from the propellant atom and this results in the propellant atom becoming
1560-426: Is unique because it requires no ignition system, the two liquids would spontaneously combust as soon as they come into contact with each other and produces the propulsion to push the spacecraft forward. The main benefit for having this technology is because that these kinds of liquids have relatively high density, which allows the volume of the propellent tank to be small, therefore increasing space efficacy. The downside
1638-607: The Sun similar to the Earth's orbit. To reach another planet, the simplest practical method is a Hohmann transfer orbit . More complex techniques, such as gravitational slingshots , can be more fuel-efficient, though they may require the probe to spend more time in transit. Some high Delta-V missions (such as those with high inclination changes ) can only be performed, within the limits of modern propulsion, using gravitational slingshots. A technique using very little propulsion, but requiring
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#17327725444011716-818: The International Space Station (ISS), and the Tiangong space station . Currently, the ISS relies on three types of cargo spacecraft: the Russian Progress , along with the American Cargo Dragon 2 , and Cygnus . China's Tiangong space station is solely supplied by the Tianzhou . The American Dream Chaser and Japanese HTV-X are under development for future use with the ISS. The European Automated Transfer Vehicle
1794-607: The James Webb Space Telescope , launched in 2021, utilizes 2 GHz S-band to enable 40 kbps real time telemetry from near the Sun–Earth L2 point . Microwave ovens operate at 2495 or 2450 MHz in the ISM band IEEE 802.16a . Some digital cordless telephones operate in this band too. 802.16e standards use a part of the frequency range of S band; under WiMAX standards. Most vendors are manufacturing equipment in
1872-590: The Manned Space Flight Network tracking stations and Apollo Orbit Determination Program was successful, with three of the Lunar Orbiters (2, 3, and 5) being tracked simultaneously from August through October 1967. The Lunar Orbiters were all eventually commanded to crash on the Moon before their attitude control fuel ran out so they would not present navigational or communications hazards to later Apollo flights. The Lunar Orbiter program
1950-663: The Space Shuttle and the International Space Station . The 10 cm radar short-band ranges roughly from 1.55 to 5.2 GHz. India's regional satellite navigation network ( IRNSS ) broadcasts on 2.483778 to 2.500278 GHz. The S band also contains the 2.4–2.483 GHz ISM band , widely used for low power unlicensed microwave devices such as cordless phones , wireless headphones ( Bluetooth ), garage door openers , keyless vehicle locks , baby monitors as well as for medical diathermy machines and microwave ovens (typically at 2.495 GHz). One of its largest uses
2028-480: The United States Air Force considers a vehicle to consist of the mission payload and the bus (or platform). The bus provides physical structure, thermal control, electrical power, attitude control and telemetry, tracking and commanding. JPL divides the "flight system" of a spacecraft into subsystems. These include: The physical backbone structure, which This is sometimes referred to as
2106-489: The spacecraft velocity , which was estimated by an electro-optical sensor. The film was then processed, scanned, and the images transmitted back to Earth. During the Lunar Orbiter missions, the first pictures of Earth as a whole were taken, beginning with Earth-rise over the lunar surface by Lunar Orbiter 1 in August, 1966. The first full picture of the whole Earth was taken by Lunar Orbiter 5 on 8 August 1967. A second photo of
2184-447: The telecommunications subsystem include radio antennas, transmitters and receivers. These may be used to communicate with ground stations on Earth, or with other spacecraft. The supply of electric power on spacecraft generally come from photovoltaic (solar) cells or from a radioisotope thermoelectric generator . Other components of the subsystem include batteries for storing power and distribution circuitry that connects components to
2262-811: The 1960s when the Apollo landing sites were being selected. Frames for sites such as the Apollo 12 landing site, the Marius Hills, and the Sulpicius Gallus rille have been released. In 2007, the Lunar Orbiter Image Recovery Project (LOIRP) began a process to convert the Lunar Orbiter Images directly from the original Ampex FR-900 analog video recordings of the spacecraft data to digital image format,
2340-412: The 2700–2900 MHz range. Particle accelerators may be powered by S-band RF sources. The frequencies are then standardized at 2.998 GHz corresponding to a wavelength of 100 mm (Europe) or 2.856 GHz (US). The National NEXRAD Radar network operates with S-band frequencies. Before implementation of this system, C-band frequencies were commonly used for weather surveillance. In
2418-552: The Air Force had offered NASA several spare cameras from the KH-7 GAMBIT program, but then authorities became concerned over security surrounding the classified cameras, including the possibility of images of the Moon giving away their resolution. Some proposals were made that NASA not publish the orbital parameters of the Lunar Orbiter probes so that the resolution of the images could not be calculated through their altitude. In
Lunar Orbiter program - Misplaced Pages Continue
2496-538: The HTML one, scroll down to see the table of contents link. Robotic spacecraft Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control , or remote guidance. They may also be autonomous , in which they have a pre-programmed list of operations that will be executed unless otherwise instructed. A robotic spacecraft for scientific measurements
2574-605: The Moon two years later. The first interstellar probe was Voyager 1 , launched 5 September 1977. It entered interstellar space on 25 August 2012, followed by its twin Voyager 2 on 5 November 2018. Nine other countries have successfully launched satellites using their own launch vehicles: France (1965), Japan and China (1970), the United Kingdom (1971), India (1980), Israel (1988), Iran (2009), North Korea (2012), and South Korea (2022). In spacecraft design,
2652-775: The Moon. In part because of high interest in the data and in part because that atlas is out of print, the task was undertaken at the Lunar and Planetary Institute to scan the large-format prints of Lunar Orbiter data. These were made available online as the Digital Lunar Orbiter Photographic Atlas of the Moon . In 2000, the Astrogeology Research Program of the US Geological Survey in Flagstaff, Arizona
2730-406: The Moon; travel through interplanetary space; flyby, orbit, or land on other planetary bodies; or enter interstellar space. Space probes send collected data to Earth. Space probes can be orbiters, landers, and rovers. Space probes can also gather materials from its target and return it to Earth. Once a probe has left the vicinity of Earth, its trajectory will likely take it along an orbit around
2808-400: The S band between 2.0 and 2.2 GHz for the creation of Mobile Satellite Service (MSS) networks in connection with Ancillary Terrestrial Components (ATC). There have been a number of companies attempting to deploy such networks, including ICO Satellite Management (now Pendrell Corporation ) and TerreStar (defunct). The 2.6 GHz range is used for China Multimedia Mobile Broadcasting ,
2886-530: The Soviet Venera 4 was the first atmospheric probe to study Venus. Mariner 4 's 1965 Mars flyby snapped the first images of its cratered surface, which the Soviets responded to a few months later with images from on its surface from Luna 9 . In 1967, America's Surveyor 3 gathered information about the Moon's surface that would prove crucial to the Apollo 11 mission that landed humans on
2964-549: The United States to be used for CBRS services and spectrum between 3.45 - 3.55 GHz and 3.7 - 3.98 GHz has been auctioned off by the FCC for 5G although this spectrum is referred to as C Band by the agency. In the United States, the FCC approved satellite-based Digital Audio Radio Service (DARS) broadcasting in the S band from 2.31 to 2.36 GHz in 1995, used by Sirius XM Radio . More recently, it has approved portions of
3042-735: The United States, the 3.55 to 3.7 GHz band is becoming shared spectrum under rules adopted by the Federal Communications Commission in April 2015 as a result of the National Broadband Plan (United States) . The biggest user of CBRS ( Citizens Broadband Radio Service ) spectrum is the United States Navy . Cable companies are planning to use the band for wireless broadband in rural areas, with Charter Communications beginning tests of
3120-548: The atmosphere and provide high-quality transmissions to small-diameter 80 cm antennas in regions that experience heavy rainfall such as Indonesia. A similar Ku- or C-band reception performance requires greater transmission power or much larger dish to penetrate the moist atmosphere. Many NASA spacecraft (near Earth and interplanetary) can communicate in the S-band, often using the Deep Space Network . For example,
3198-408: The average micrometeoroid flux near the Moon was about two orders of magnitude greater than in interplanetary space, but slightly less than in the near-Earth environment. The radiation experiments confirmed that the design of Apollo hardware would protect the astronauts from average and greater than average short term exposure to solar particle events. The use of Lunar Orbiters for tracking to evaluate
Lunar Orbiter program - Misplaced Pages Continue
3276-409: The base of the craft held the battery, transponder , flight programmer, inertial reference unit (IRU), Canopus star tracker , command decoder, multiplex encoder, traveling-wave tube amplifier (TWTA), and the photographic system. Four solar panels were mounted to extend out from this deck with a total span across of 3.72 m (12.2 ft). Also extending out from the base of the spacecraft were
3354-456: The basis of much of lunar scientific research. Because they were obtained at low to moderate Sun angles, the Lunar Orbiter photographic mosaics are particularly useful for studying the morphology of lunar topographic features. Several atlases and books featuring Lunar Orbiter photographs have been published. Perhaps the most definitive was that of Bowker and Hughes (1971); it contained 675 photographic plates with approximately global coverage of
3432-450: The combustion of the fuel can only occur due to a presence of a catalyst . This is quite advantageous due to making the rocket engine lighter and cheaper, easy to control, and more reliable. But, the downfall is that the chemical is very dangerous to manufacture, store, and transport. A bipropellant propulsion system is a rocket engine that uses a liquid propellant. This means both the oxidizer and fuel line are in liquid states. This system
3510-453: The command and data subsystem. It is often responsible for: This system is mainly responsible for the correct spacecraft's orientation in space (attitude) despite external disturbance-gravity gradient effects, magnetic-field torques, solar radiation and aerodynamic drag; in addition it may be required to reposition movable parts, such as antennas and solar arrays. Integrated sensing incorporates an image transformation algorithm to interpret
3588-552: The end, NASA's existing camera systems, while lower resolution, proved to be adequate for the needs of the mission. Kodak created and constructed built eight photographic subsystems for the Lunar Orbiter program, five of which were used in space missions of 1966 and 1967. The camera used two lenses to simultaneously expose a wide-angle and a high-resolution image on the same film. The wide-angle, medium resolution mode used an 80 mm F 2.8 Xenotar lens manufactured by Schneider Kreuznach of West Germany. The high-resolution mode used
3666-401: The engine protruded through the center of the shield. Mounted on the perimeter of the top deck were four attitude control thrusters. Power of 375 W was provided by the four solar arrays containing 10,856 n/p solar cells which would directly run the spacecraft and also charge the 12 A·h nickel-cadmium battery . The batteries were used during the brief periods of occultation when no solar power
3744-713: The entire sky ( astronomical survey ), and satellites which focus on selected astronomical objects or parts of the sky and beyond. Space telescopes are distinct from Earth imaging satellites , which point toward Earth for satellite imaging , applied for weather analysis , espionage , and other types of information gathering . Cargo or resupply spacecraft are robotic vehicles designed to transport supplies, such as food, propellant, and equipment, to space stations. This distinguishes them from space probes, which are primarily focused on scientific exploration. Automated cargo spacecraft have been servicing space stations since 1978, supporting missions like Salyut 6 , Salyut 7 , Mir ,
3822-459: The fall of 1951. The first artificial satellite , Sputnik 1 , was put into a 215-by-939-kilometer (116 by 507 nmi) Earth orbit by the USSR on 4 October 1957. On 3 November 1957, the USSR orbited Sputnik 2 . Weighing 113 kilograms (249 lb), Sputnik 2 carried the first animal into orbit, the dog Laika . Since the satellite was not designed to detach from its launch vehicle 's upper stage,
3900-415: The far side, and Lunar Orbiter 5 completed the far side coverage and acquired medium (20 m or 66 ft) and high (2 m or 6 ft 7 in) resolution images of 36 preselected areas. All of the Lunar Orbiter spacecraft were launched by Atlas-Agena -D launch vehicles. The Lunar Orbiters had an imaging system which consisted of a dual-lens camera , a film processing unit, a readout scanner, and
3978-608: The ground. Increased autonomy is important for distant probes where the light travel time prevents rapid decision and control from Earth. Newer probes such as Cassini–Huygens and the Mars Exploration Rovers are highly autonomous and use on-board computers to operate independently for extended periods of time. A space probe is a robotic spacecraft that does not orbit Earth, but instead, explores further into outer space. Space probes have different sets of scientific instruments onboard. A space probe may approach
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#17327725444014056-521: The immediate imagery land data, perform a real-time detection and avoidance of terrain hazards that may impede safe landing, and increase the accuracy of landing at a desired site of interest using landmark localization techniques. Integrated sensing completes these tasks by relying on pre-recorded information and cameras to understand its location and determine its position and whether it is correct or needs to make any corrections (localization). The cameras are also used to detect any possible hazards whether it
4134-475: The mosaics were created and several copies were distributed across the U.S. to NASA image and data libraries known as Regional Planetary Information Facilities . The resulting outstanding views were of generally very high spatial resolution and covered a substantial portion of the lunar surface, but they suffered from a "venetian blind" striping, missing or duplicated data, and frequent saturation effects that hampered their use. For many years these images have been
4212-427: The most powerful form of propulsion there is. For a propulsion system to work, there is usually an oxidizer line and a fuel line. This way, the spacecraft propulsion is controlled. But in a monopropellant propulsion, there is no need for an oxidizer line and only requires the fuel line. This works due to the oxidizer being chemically bonded into the fuel molecule itself. But for the propulsion system to be controlled,
4290-402: The only way to explore them. Telerobotics also allows exploration of regions that are vulnerable to contamination by Earth micro-organisms since spacecraft can be sterilized. Humans can not be sterilized in the same way as a spaceship, as they coexist with numerous micro-organisms, and these micro-organisms are also hard to contain within a spaceship or spacesuit. The first uncrewed space mission
4368-518: The original film into a series of strips. The data were written to magnetic tape and also to film. The film data were used to create hand-made mosaics of Lunar Orbiter frames. Each LO exposure resulted in two photographs: medium-resolution frames recorded by the 80-mm focal-length lens and high-resolution frames recorded by the 610-mm focal length lens. Due to their large size, HR frames were divided into three sections, or sub-frames. Large-format prints (16 by 20 inches (410 mm × 510 mm)) from
4446-408: The power sources. Spacecraft are often protected from temperature fluctuations with insulation. Some spacecraft use mirrors and sunshades for additional protection from solar heating. They also often need shielding from micrometeoroids and orbital debris. Spacecraft propulsion is a method that allows a spacecraft to travel through space by generating thrust to push it forward. However, there
4524-489: The project in the summer of 1967 after the complete success of the Lunar Orbiters. The Lunar Orbiter program consisted of five spacecraft which returned photography of 99 percent of the surface of the Moon (near and far side ) with resolution down to 1 meter (3 ft 3 in). Altogether the Orbiters returned 2180 high resolution and 882 medium resolution frames. The micrometeoroid experiments recorded 22 impacts showing
4602-641: The range of 3.5 GHz. The exact frequency range allocated for this type of use varies between countries. In North America, 2.4–2.483 GHz is an ISM band used for unlicensed spectrum devices such as cordless phones , wireless headphones , and video senders , among other consumer electronics uses, including Bluetooth which operates between 2.402 GHz and 2.480 GHz. Amateur radio and amateur satellite operators have two S-band allocations, 13 cm (2.4 GHz) and 9 cm (3.4 GHz). Amateur television repeaters also operate in these bands. Airport surveillance radars typically operate in
4680-536: The robotic spacecraft requires accurate knowledge of where the spacecraft is located relative to the surface (localization), what may pose as hazards from the terrain (hazard assessment), and where the spacecraft should presently be headed (hazard avoidance). Without the capability for operations for localization, hazard assessment, and avoidance, the robotic spacecraft becomes unsafe and can easily enter dangerous situations such as surface collisions, undesirable fuel consumption levels, and/or unsafe maneuvers. Components in
4758-468: The service in January 2018. The band is also used as a transmit intermediate frequency in satellite communications as a replacement for L band where a single/shared coaxial connection is used between the modem/IDU and antenna/ODU for both the transmit and receive signals. This is to prevent interference between the transmit and receive signals which would otherwise not occur on a dual coaxial setup where
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#17327725444014836-539: The space stations Salyut 7 and Mir , and the International Space Station module Zarya , were capable of remote guided station-keeping and docking maneuvers with both resupply craft and new modules. Uncrewed resupply spacecraft are increasingly used for crewed space stations . The first robotic spacecraft was launched by the Soviet Union (USSR) on 22 July 1951, a suborbital flight carrying two dogs Dezik and Tsygan. Four other such flights were made through
4914-408: The spacecraft forward. This happens due to one basic principle known as Newton's Third Law . According to Newton, "to every action there is an equal and opposite reaction." As the energy and heat is being released from the back of the spacecraft, gas particles are being pushed around to allow the spacecraft to propel forward. The main reason behind the usage of rocket engine today is because rockets are
4992-414: The spacecraft is robotic. Robotic spacecraft use telemetry to radio back to Earth acquired data and vehicle status information. Although generally referred to as "remotely controlled" or "telerobotic", the earliest orbital spacecraft – such as Sputnik 1 and Explorer 1 – did not receive control signals from Earth. Soon after these first spacecraft, command systems were developed to allow remote control from
5070-550: The stripes that had been noticeable in the original photographic frames. Because of its emphasis on construction of a global mosaic, this project only scanned about 15% of the available Lunar Orbiter photographic frames. Data from Lunar Orbiter missions III , IV and V were included in the global mosaic. In addition, the USGS digitization project created frames from very high resolution Lunar Orbiter images for several 'sites of scientific interest.' These sites had been identified in
5148-423: The thrust to propel the spacecraft forward. The advantage of having this kind of propulsion is that it is incredibly efficient in maintaining constant velocity, which is needed for deep-space travel. However, the amount of thrust produced is extremely low and that it needs a lot of electrical power to operate. Mechanical components often need to be moved for deployment after launch or prior to landing. In addition to
5226-421: The total mass in orbit was 508.3 kilograms (1,121 lb). In a close race with the Soviets , the United States launched its first artificial satellite, Explorer 1 , into a 357-by-2,543-kilometre (193 by 1,373 nmi) orbit on 31 January 1958. Explorer I was an 205-centimetre (80.75 in) long by 15.2-centimetre (6.00 in) diameter cylinder weighing 14.0 kilograms (30.8 lb), compared to Sputnik 1,
5304-530: The transmit and receive signals are separate and both can use the whole L-band frequency range. In a single coaxial connection using S-Band to "frequency shift" the transmit signal away from L band, a multiplier such as 10, is usually applied to form the SHF frequency. For example, the modem would transmit at 2.815 GHz IF (S Band) to the ODU and then the ODU up-converts this signal to 28.15 GHz SHF ( Ka Band ) towards
5382-531: The use of motors, many one-time movements are controlled by pyrotechnic devices. Robotic spacecraft are specifically designed system for a specific hostile environment. Due to their specification for a particular environment, it varies greatly in complexity and capabilities. While an uncrewed spacecraft is a spacecraft without personnel or crew and is operated by automatic (proceeds with an action without human intervention) or remote control (with human intervention). The term 'uncrewed spacecraft' does not imply that
5460-422: The whole Earth was taken by Lunar Orbiter 5 on 10 November 1967. The Boeing-Eastman Kodak proposal was announced by NASA on 20 December 1963. The main bus of the Lunar Orbiter had the general shape of a truncated cone, 1.65 m (5 ft 5 in) tall and 1.5 m (4 ft 11 in) in diameter at the base. The spacecraft was composed of three decks supported by trusses and an arch. The equipment deck at
5538-437: Was Sputnik , launched October 4, 1957 to orbit the Earth. Nearly all satellites , landers and rovers are robotic spacecraft. Not every uncrewed spacecraft is a robotic spacecraft; for example, a reflector ball is a non-robotic uncrewed spacecraft. Space missions where other animals but no humans are on-board are called uncrewed missions. Many habitable spacecraft also have varying levels of robotic features. For example,
5616-793: Was adapted under permission of the NRO from the SAMOS E-1 reconnaissance camera, built by Kodak for a short-lived USAF near-realtime satellite imaging project. As a backup for the Lunar Orbiter program, NASA and the NRO cooperated on the Lunar Mapping and Survey System (LM&SS), based on the KH-7 reconnaissance satellite. Replacing the Lunar Module in the Saturn V , Apollo astronauts would operate LM&SS remotely in lunar orbit. NASA canceled
5694-490: Was available. Propulsion for major maneuvers was provided by the gimballed velocity control engine, a hypergolic 440 newtons (100 lbf) thrust Marquardt Corp. rocket motor. Three axis stabilization and attitude control were provided by four 4 newtons (1 lbf) nitrogen gas jets. Navigational knowledge was provided by five Sun sensors , the Canopus star sensor, and the inertial navigation system. Communications were via
5772-704: Was funded by NASA (as part of the Lunar Orbiter Digitization Project Archived 2017-11-23 at the Wayback Machine ) to scan at 25 micrometer resolution archival LO positive film strips that were produced from the original data. The goal was to produce a global mosaic of the Moon using the best available Lunar Orbiter frames (largely the same coverage as that of Bowker and Hughes, 1971). The frames were constructed from scanned film strips; they were digitally constructed, geometrically controlled, and map-projected without
5850-453: Was launched in April 2009 and is located at 10° East. In Indonesia , S band is used by MNC Vision for Direct-to-Home satellite television (unlike similar services in most countries, which use K u band ). The frequency typically allocated for this service is 2.5 to 2.7 GHz (LOF 1.570 GHz). IndoStar-1 was the world's first commercial communications satellite to use S-band frequencies for broadcast, which efficiently penetrate
5928-525: Was managed by NASA Langley Research Center at a total cost of roughly $ 200 million. Doppler tracking of the five orbiters allowed mapping of the gravitational field of the Moon and discovery of mass concentrations (mascons), or gravitational highs, which were located in the centers of some (but not all) of the lunar maria. Below is the flight log information of the five Lunar Orbiter photographic missions: The Lunar Orbiter orbital photographs were transmitted to Earth as analog data after onboard scanning of
6006-479: Was previously used between 2008 and 2015. Solar System → Local Interstellar Cloud → Local Bubble → Gould Belt → Orion Arm → Milky Way → Milky Way subgroup → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster → Local Hole → Observable universe → Universe Each arrow ( → ) may be read as "within" or "part of". S band The S band
6084-550: Was the Luna E-1 No.1 , launched on 23 September 1958. The goal of a lunar probe repeatedly failed until 4 January 1959 when Luna 1 orbited around the Moon and then the Sun. The success of these early missions began a race between the US and the USSR to outdo each other with increasingly ambitious probes. Mariner 2 was the first probe to study another planet, revealing Venus' extremely hot temperature to scientists in 1962, while
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