A sample-return mission is a spacecraft mission with the goal of collecting and returning samples from an extraterrestrial location to Earth for analysis. Sample-return missions may bring back atoms and molecules or a deposit of complex compounds such as loose material and rocks; these samples may be obtained in a number of ways, such as soil and rock excavation or a collector array used for capturing particles of solar wind or cometary debris. To date, samples of Moon rock from Earth's Moon have been collected by robotic and crewed missions, the comet Wild 2 and the asteroid 25143 Itokawa have been visited by a robotic spacecraft which returned samples to Earth, samples of the solar wind have been returned by a robotic mission. In addition to sample-return missions, samples from three identified non-terrestrial bodies have been collected by means other than sample-return missions: samples from the Moon in the form of Lunar meteorites, samples from Mars in the form of Martian meteorites, samples from Vesta in the form of HED meteorites.
Samples available on Earth can be analyzed in laboratories, so we can further our understanding and knowledge as part of the discovery and exploration of the Solar System. Until now many important scientific discoveries about the Solar System were made remotely with telescopes, some Solar System bodies were visited by orbiting or landing spacecraft with instruments capable of remote sensing or sample analysis. While such an investigation of the Solar System is technically easier than a sample-return mission, the scientific tools available on Earth to study such samples are far more advanced and diverse than those that can go on spacecraft. Analysis of samples on Earth allows to follow up any findings with different tools, including tools that have yet to be developed. Samples analyzed on Earth can be matched against findings of remote sensing, for more insight into the processes that formed the Solar System; this was done, for example, with findings by the Dawn spacecraft, which visited the asteroid Vesta from 2011 to 2012 for imaging, samples from HED meteorites, which were compared to data gathered by Dawn.
These meteorites could be identified as material ejected from the large impact crater Rheasilvia on Vesta. This allowed deducing the composition of crust and core of Vesta; some differences in composition of asteroids can be discerned by imaging alone. However, for a more precise inventory of the material on these different bodies, more samples will be collected and returned in the future, to match their compositions with the data gathered through telescopes and astronomical spectroscopy. One further focus of such investigation—besides the basic composition and geologic history of the various Solar System bodies—is the presence of the building blocks of life on comets, Mars or the moons of the gas giants. Several sample-return missions to asteroids and comets are in the works. More samples from asteroids and comets will help determine whether life formed in space and was carried to Earth by meteorites. Another question under investigation is whether extraterrestrial life formed on other Solar System bodies like Mars or on the moons of the gas giants, whether life might exist there.
The result of NASA's last "Decadal Survey" was to prioritize a Mars sample-return mission, as Mars has a special importance: it is comparatively "nearby", might have harbored life in the past, might continue to sustain life. Jupiter's moon Europa is another important focus in the search for life in the Solar System. However, due to the distance and other constraints, Europa might not be the target of a sample-return mission in the foreseeable future. Planetary protection aims to prevent biological contamination of both the target celestial body and the Earth—in the case of sample-return missions. No sample has yet been returned with alien life in it. A sample-return from Mars or other location with potential to host life, is a category V mission under COSPAR which directs to containment of any unsterilized sample returned to Earth; this is because it is unknown the effects of such hypothetical life would be on humans or on the biosphere of Earth. For this reason, Carl Sagan and Joshua Lederberg argued in the 1970s that we should do sample-return missions classified as category V missions with extreme caution, studies by the NRC and ESF agreed.
The Apollo program returned over 382 kg of lunar rocks and regolith to the Lunar Receiving Laboratory in Houston. Today, 75% of the samples are stored at the Lunar Sample Laboratory Facility built in 1979. In July 1969, Apollo 11 achieved the first successful sample return from another Solar System body, it returned 22 kilograms of Lunar surface material. This was followed by 34 kilograms of material from Apollo 12, 42.8 kilograms of material from Apollo 14, 76.7 kilograms of material from Apollo 15, 94.3 kilograms of material from Apollo 16, 110.4 kilograms of material from Apollo 17. One of the most significant advances in sample-return missions occurred in 1970 when the robotic Soviet mission known as Luna 16 returned 101 grams of lunar soil. Luna 20 returned 55 grams in 1974, Luna 24 returned 170 grams in 1976. Although they recovered far less than the Apollo missions, they did this automatically. Apart from these three successes, other attempts under the Luna programme failed; the first two missions were intended to outstrip Apollo 11 and wer
Apollo 13 was the seventh manned mission in the Apollo space program and the third intended to land on the Moon. The craft was launched on April 11, 1970 from the Kennedy Space Center, but the lunar landing was aborted after an oxygen tank exploded two days crippling the service module upon which the command module had depended. Despite great hardship caused by limited power, loss of cabin heat, shortage of potable water, the critical need to make makeshift repairs to the carbon dioxide removal system, the crew returned safely to Earth on April 17, 1970, six days after launch; the flight passed the far side of the Moon at an altitude of 254 kilometers above the lunar surface, 400,171 km from Earth, a spaceflight record marking the farthest humans have traveled from Earth. The mission was commanded by James A. Lovell with John L. "Jack" Swigert as Command Module Pilot and Fred W. Haise as Lunar Module Pilot. Swigert was a late replacement for the original CM pilot Ken Mattingly, grounded by the flight surgeon after exposure to German measles.
The story of the Apollo 13 mission has been dramatized multiple times, most notably in the 1995 film Apollo 13. According to the standard crew rotation in place during the Apollo program, the prime crew for Apollo 13 would have been the backup crew for Apollo 10 with Mercury and Gemini veteran L. Gordon Cooper in command; that crew was composed of Commander L. Gordon Cooper Jr.. Deke Slayton, NASA's Director of Flight Crew Operations, never intended to rotate Cooper and Eisele to another mission, as both were out of favor with NASA management for various reasons, he assigned them to the backup crew because of a lack of flight-qualified manpower in the Astronaut Office at the time the assignment needed to be made. Slayton felt Cooper had no more than a small chance of receiving the Apollo 13 command, if he did an outstanding job with the assignment, which he did not. Despite Eisele's issues with management, Slayton always intended to assign him to a future Apollo Applications Program mission rather than a lunar mission, but this program was cut down to only the Skylab component.
Thus, the original assignment Slayton submitted to his superiors for this flight was: Commander Alan B. Shepard Jr.. For the first time Slayton's recommendation was rejected by management, who felt that Shepard needed more time to train properly for a lunar flight, as he had only benefited from experimental surgery to correct an inner ear disorder which had kept him grounded since his first Mercury flight in 1961. Thus, Lovell's crew, backup for the historic Apollo 11 mission and therefore slated for Apollo 14, was swapped with Shepard's crew and the original crew selection for the mission became: Prime crew: Backup crew: Ken Mattingly was intended as the Command Module Pilot. Seven days before launch, the backup lunar module pilot, Charlie Duke, contracted rubella from one of his children; this exposed both the backup crews, who trained together. Mattingly was found to be the only one of the other five who had not had rubella as a child and thus was not immune. Three days before launch, at the insistence of the Flight Surgeon, Swigert was moved to the prime crew.
Mattingly never contracted rubella and was assigned after the mission as command module pilot to Young's crew, which flew Apollo 16, the fifth mission to land on the Moon. Vance D. Brand. Gene Kranz – White team; the astronauts' mission insignia was sculpted as a medallion depicting Steeds of Apollo by Lumen Martin Winter and was struck by the Franklin Mint. Mass: CSM Odyssey 63,470 pounds; the Apollo 13 mission was to explore the Fra Mauro formation, or Fra Mauro highlands, named after the 80-kilometer diameter Fra Mauro crater located within it. It is a widespread, hilly selenological area thought to be composed of ejecta from the impact that formed Mare Imbrium; the next Apollo mission, Apollo 14 made a successful flight to Fra Mauro. April 14, 1970 UTC Oxygen tank explosion: 03:07:53 UTC. Crew was on board USS Iwo Jima 45 minutes later; the mission was launched at the planned time, 02:13:00 PM EST on April 11. An anomaly occurred; the four outboard engines and the third-stage engine burned longer to compensate, the vehicle achieved close to the planned circular 100 nautical miles parking orbit, followed by a normal translunar injection about two hours later.
The engine shutdown was determined to be caused by severe pogo oscillations measured at a strength of 68 g and a frequency of 16 hertz, flexing the thrust frame by 3 inches. The vehicle's guidance system shut the engine down in response to sensed thrust chamber pressure fluctuations. Pogo oscillations had been seen on previous Titan rockets, on the Saturn V during Apollo 6, but on Apollo 13, they were amplified by
A satellite bus or spacecraft bus is a general model on which multiple-production satellite spacecraft are based. The bus is the infrastructure of the spacecraft providing locations for the payload. Bus-derived satellites are opposed to specially produced satellites. Bus-derived satellites are customized to customer requirements, for example with specialized sensors or transponders, in order to achieve a specific mission, they are used for geosynchronous satellites communications satellites, but are used in spacecraft which occupy lower orbits including low Earth orbit missions. Some satellite bus examples include: Boeing DS&S 702 Lockheed Martin Space Systems A2100 Alphabus INVAP ARSAT-3K Airbus D&S Eurostar ISRO's I-1K, I-2K, I-3K, I-4K, I-6K, Indian Mini Satellite bus NASA Ames MCSB SSL 1300 Orbital ATK GEOStar Mitsubishi Electric DS2000 Spacecraft Bus A bus consists of the following subsystems: Command and Data Handling System Communications system and antennas Electrical Power System Propulsion Thermal control Attitude Control System Guidance and control System Structures and trusses Life support.
Comparison of satellite buses Service module Satellite Satellite Glossary JWST Observatory: The Spacecraft Bus Spitzer's Spacecraft Bus Gunter's Space Page: Spacecraft buses
A robotic spacecraft is an uncrewed spacecraft under telerobotic control. A robotic spacecraft designed to make scientific research measurements is called a space probe. Many space missions are more suited to telerobotic rather than crewed operation, due to lower cost and lower 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 and Neptune are too distant to reach with current crewed spacecraft technology, so telerobotic probes are the only way to explore them. Many artificial satellites are robotic spacecraft, as are many rovers; the first robotic spacecraft was launched by the Soviet Union on 22 July 1951, a suborbital flight carrying two dogs Dezik and Tsygan. Four other such flights were made through the fall of 1951; the first artificial satellite, Sputnik 1, was put into a 215-by-939-kilometer Earth orbit by the USSR) on 4 October 1957. On 3 November 1957, the USSR orbited Sputnik 2.
Weighing 113 kilograms, Sputnik 2 carried the first living animal into the dog Laika. Since the satellite was not designed to detach from its launch vehicle's upper stage, the total mass in orbit was 508.3 kilograms. In a close race with the Soviets, the United States launched its first artificial satellite, Explorer 1, into a 193-by-1,373-nautical-mile orbit on 31 January 1958. Explorer I was a 80.75-inch long by 6.00-inch diameter cylinder weighing 30.8 pounds, compared to Sputnik 1, a 58-centimeter sphere which weighed 83.6 kilograms. 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, about the size of a grapefruit, remains in a 360-by-2,080-nautical-mile orbit as of 2016. Nine other countries have launched satellites using their own launch vehicles: France and China, the United Kingdom, Israel, North Korea, New Zealand.
In spacecraft design, the United States Air Force considers a vehicle to consist of the mission payload and the bus. The bus provides physical structure, thermal control, electrical power, attitude control and telemetry and commanding. JPL divides the "flight system" of a spacecraft into subsystems; these include: This is the physical backbone structure. It: provides overall mechanical integrity of the spacecraft ensures spacecraft components are supported and can withstand launch loads This is sometimes referred to as the command and data subsystem, it is responsible for: command sequence storage maintaining the spacecraft clock collecting and reporting spacecraft telemetry data collecting and reporting mission data This system is responsible for the correct spacecraft's orientation in space despite external disturbance-gravity gradient effects, magnetic-field torques, solar radiation and aerodynamic drag. 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 a entry into the planetary gravity field and atmosphere, a descent through that atmosphere towards a intended/targeted region of scientific value, 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 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 efficiently perform hazard assessment and trajectory adjustments in real time to avoid hazards. To achieve this, the robotic spacecraft requires accurate knowledge of where the spacecraft is located relative to the surface, what may pose as hazards from the terrain, where the spacecraft should presently be headed. Without the capability for operations for localization, hazard assessment, avoidance, the robotic spacecraft becomes unsafe and can enter dangerous situations such as surface collisions, undesirable fuel consumption levels, and/or unsafe maneuvers.
Integrated sensing incorporates an image transformation algorithm to interpret the immediate imagery land data, perform a real-time detection and avoidance of terrain hazards that may impede safe landing, 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; the cameras are used to detect any possible hazards whether it 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 not ideal. Components in the telecommunications subsystem include radio antennas and receivers; these may be used to communicate with other spacecraft. The supply of electric power on spacecraft come from photovoltaic cells or from a radioisotope thermoelectric generator. Other components of the subsystem include batteries for storing power and distribution circuitry that conne
Lunar Reconnaissance Orbiter
The Lunar Reconnaissance Orbiter is a NASA robotic spacecraft orbiting the Moon in an eccentric polar mapping orbit. Data collected by LRO has been described as essential for planning NASA's future human and robotic missions to the Moon, its detailed mapping program is identifying safe landing sites, locating potential resources on the Moon, characterizing the radiation environment, demonstrating new technologies. Launched on June 18, 2009, in conjunction with the Lunar Crater Observation and Sensing Satellite, as the vanguard of NASA's Lunar Precursor Robotic Program, LRO was the first United States mission to the Moon in over ten years. LRO and LCROSS were launched as part of the United States's Vision for Space Exploration program; the probe has made a 3-D map of the Moon's surface at 100-meter resolution and 98.2% coverage, including 0.5-meter resolution images of Apollo landing sites. The first images from LRO were published on July 2, 2009, showing a region in the lunar highlands south of Mare Nubium.
The total cost of the mission is reported as US$583 million, of which $504 million pertains to the main LRO probe and $79 million to the LCROSS satellite. Developed at NASA's Goddard Space Flight Center, LRO is a sophisticated spacecraft, its mission duration was planned for one year, but has since been extended numerous times after review by NASA. After completing a preliminary design review in February 2006 and a critical design review in November 2006, the LRO was shipped from Goddard to Cape Canaveral Air Force Station on February 11, 2009. Launch was planned for October 2008, but this slid to April as the spacecraft underwent testing in a thermal vacuum chamber. Launch was rescheduled for June 17, 2009, because of the delay in a priority military launch, happened one day on June 18; the one-day delay was to allow the Space Shuttle Endeavour a chance to lift off for mission STS-127 following a hydrogen fuel leak that canceled an earlier planned launch. Areas of investigation include selenodetic global topography.
In addition, LRO has provided images and precise locations of landers and equipment from previous American and Russian lunar missions, including the Apollo sites. The orbiter carries a complement of six instruments and one technology demonstration: Cosmic Ray Telescope for the Effects of Radiation The primary goal of the Cosmic Ray Telescope for the Effects of Radiation is to characterize the global lunar radiation environment and its biological impacts. Diviner The Diviner Lunar Radiometer Experiment measures lunar surface thermal emission to provide information for future surface operations and exploration. Lyman-Alpha Mapping Project The Lyman-Alpha Mapping Project peers into permanently shadowed craters in search of water ice, using ultraviolet light generated by stars as well as the hydrogen atoms that are thinly spread throughout the Solar System. Lunar Exploration Neutron Detector The Lunar Exploration Neutron Detector provides measurements, creates maps, detects possible near-surface water ice deposits.
Lunar Orbiter Laser Altimeter The Lunar Orbiter Laser Altimeter investigation provides a precise global lunar topographic model and geodetic grid. Lunar Reconnaissance Orbiter Camera The Lunar Reconnaissance Orbiter Camera addresses the measurement requirements of landing site certification and polar illumination. LROC comprises a pair of a single wide-angle camera. LROC has flown several times over the historic Apollo lunar landing sites at 50 km altitude; the mission is returning 70–100 terabytes of image data. It is expected that this photography will boost public acknowledgement of the validity of the landings, further discredit Apollo conspiracy theories. Mini-RF The Miniature Radio Frequency radar demonstrated new lightweight SAR and communications technologies and located potential water-ice. Prior to the LRO's launch, NASA gave members of the public the opportunity to have their names placed in a microchip on the LRO; the deadline for this opportunity was July 31, 2008. About 1.6 million names were submitted.
On June 23, 2009, the Lunar Reconnaissance Orbiter entered into orbit around the Moon after a four-and-a-half-day journey from the Earth. When launched, the spacecraft was aimed at a point ahead of the Moon's position. A mid-course correction was required during the trip in order for the spacecraft to enter Lunar orbit. Once the spacecraft reached the far side of the Moon, its rocket motor was fired in order for it to be captured by the Moon's gravity into an elliptical lunar orbit. A series of four rocket burns over the next four days put the satellite into its commissioning phase orbit where each instrument was brought online and tested. On September 15, 2009, the spacecraft started its primary mission by orbiting the Moon at about 50 km for one year. After completing its one-year exploration phase, in September 2010, LRO was handed over to NASA's Science Mission Directorate to continue the science phase of the mission, it will continue in its 50 km circular orbit, but will be transitioned into a fuel-conserving elliptical orbit for the remainder of the mission.
NASA's LCROSS mis
Chang'e 4 is a Chinese lunar exploration mission that achieved the first soft landing on the far side of the Moon, on 3 January 2019. A communication relay satellite, was first launched to a halo orbit near the Earth-Moon L2 point in May 2018; the robotic lander and Yutu 2 rover were launched on 7 December 2018 and entered orbit around the Moon on 12 December 2018. The mission is the follow-up to the first Chinese landing on the Moon; the spacecraft was built as a backup for Chang'e 3 and became available after Chang'e 3 landed in 2013. The configuration of Chang'e 4 was adjusted to meet new scientific objectives. Like its predecessors, the mission is named after Chang ` the Chinese Moon goddess; the Chinese Lunar Exploration Program is designed to be conducted in three phases of incremental technological advancement: the first is to reach lunar orbit, a task completed by Chang'e 1 in 2007 and Chang'e 2 in 2010. The program aims to facilitate a crewed lunar landing in the 2030s and build an outpost near the south pole.
The Chinese Lunar Exploration Program has started to incorporate private investment from individuals and enterprises for the first time, a move aimed at accelerating aerospace innovation, cutting production costs, promoting military–civilian relationships. The Chang'e 4 mission was first scheduled for launch in 2015 as part of the second phase of the Chinese Lunar Exploration Program, but the adjusted objectives and design of the mission imposed delays, launched on 7 December 2018, 18:23 UTC. The spacecraft entered lunar orbit on 12 December 2018, 08:45 UTC; the orbit's perilune was lowered to 15 km on 30 December 2018, 00:55 UTC. Landing took place on 3 January 2019 at 02:26 UTC, shortly after lunar sunrise over the crater Von Kármán; this mission will attempt to determine the age and composition of an unexplored region of the Moon, as well as develop technologies required for the stages of the program. An ancient collision event on the Moon left behind a large crater, called the Aitken Basin, now about 13 km deep, it is thought that the massive impactor exposed the deep lunar crust, the mantle materials.
If Chang'e 4 can find and study some of this material, it would get an unprecedented view into the Moon's internal structure and origins. The specific scientific objectives are: Measure the chemical compositions of lunar rocks and soils Measure lunar surface temperature over the duration of the mission. Carry out low-frequency radio astronomical observation and research using a radio telescope Study of cosmic rays Observe the solar corona, investigate its radiation characteristics and mechanism, to explore the evolution and transport of coronal mass ejections between the Sun and Earth. Direct communication with Earth is impossible on the far side of the Moon, since transmissions are blocked by the Moon. Communications must go through a communications relay satellite, placed at a location that has a clear view of both the landing site and the Earth. On 20 May 2018, the China National Space Administration launched the Queqiao relay satellite to a halo orbit around the Earth–Moon L2 point; the relay satellite is based on the Chang'e 2 design, has a mass of 425 kg, it uses a 4.2 m antenna to receive X band signals from the lander and rover, relay them to Earth control on the S band.
The spacecraft took 24 days to reach L2. On 14 June 2018, Queqiao finished its final adjustment burn and entered the L2 halo mission orbit, about 65,000 kilometres from the Moon; this is the first lunar relay satellite at this location. The name Queqiao came from the Chinese tale The Cowherd and the Weaver Girl; as part of the Chang'e 4 mission, two microsatellites named Longjiang-1 and Longjiang-2, were launched along with Queqiao in May 2018. Longjiang-1 failed to enter lunar orbit, but Longjiang-2 succeeded and is operational in lunar orbit; these microsatellites were tasked to observe the sky at low frequencies, corresponding to wavelengths of 300 to 10 metres, with the aim of studying energetic phenomena from celestial sources. Due to the Earth's ionosphere, no observations in this frequency range have been done in Earth orbit, offering potential breakthrough science; as is the case with many of China's space missions, the details of the spacecraft and the mission have been limited. What is known is that much of the Chang'e 4 lander and rover design is modeled after Chang'e-3 and its Yutu rover.
In fact, Chang'e 4 was built as a backup to Chang'e 3, based on the experience and results from that mission, Chang'e 4 was adapted to the specifics of the new mission. The lander and rover were launched on 7 December 2018, 18:23 UTC, six months after the launch of the Queqiao relay satellite; the total landing mass is 1,200 kg. Both the stationary lander and Yutu-2 rover are equipped with a radioisotope heater unit in order to heat their subsystems during the long lunar nights, while electrical power is generated by solar panels. After landing, the lander extended a ramp to deploy the Yutu-2 rover to the lunar surface; the rover measures 1.5 × 1.0 × 1
The Apollo program known as Project Apollo, was the third United States human spaceflight program carried out by the National Aeronautics and Space Administration, which succeeded in landing the first humans on the Moon from 1969 to 1972. First conceived during Dwight D. Eisenhower's administration as a three-man spacecraft to follow the one-man Project Mercury which put the first Americans in space, Apollo was dedicated to President John F. Kennedy's national goal of "landing a man on the Moon and returning him safely to the Earth" by the end of the 1960s, which he proposed in an address to Congress on May 25, 1961, it was the third US human spaceflight program to fly, preceded by the two-man Project Gemini conceived in 1961 to extend spaceflight capability in support of Apollo. Kennedy's goal was accomplished on the Apollo 11 mission when astronauts Neil Armstrong and Buzz Aldrin landed their Apollo Lunar Module on July 20, 1969, walked on the lunar surface, while Michael Collins remained in lunar orbit in the command and service module, all three landed safely on Earth on July 24.
Five subsequent Apollo missions landed astronauts on the Moon, the last in December 1972. In these six spaceflights, twelve men walked on the Moon. Apollo ran from 1961 to 1972, with the first manned flight in 1968, it achieved its goal of manned lunar landing, despite the major setback of a 1967 Apollo 1 cabin fire that killed the entire crew during a prelaunch test. After the first landing, sufficient flight hardware remained for nine follow-on landings with a plan for extended lunar geological and astrophysical exploration. Budget cuts forced the cancellation of three of these. Five of the remaining six missions achieved successful landings, but the Apollo 13 landing was prevented by an oxygen tank explosion in transit to the Moon, which destroyed the service module's capability to provide electrical power, crippling the CSM's propulsion and life support systems; the crew returned to Earth safely by using the lunar module as a "lifeboat" for these functions. Apollo used Saturn family rockets as launch vehicles, which were used for an Apollo Applications Program, which consisted of Skylab, a space station that supported three manned missions in 1973–74, the Apollo–Soyuz Test Project, a joint US-Soviet Union Earth-orbit mission in 1975.
Apollo set several major human spaceflight milestones. It stands alone in sending manned missions beyond low Earth orbit. Apollo 8 was the first manned spacecraft to orbit another celestial body, while the final Apollo 17 mission marked the sixth Moon landing and the ninth manned mission beyond low Earth orbit; the program returned 842 pounds of lunar rocks and soil to Earth contributing to the understanding of the Moon's composition and geological history. The program laid the foundation for NASA's subsequent human spaceflight capability and funded construction of its Johnson Space Center and Kennedy Space Center. Apollo spurred advances in many areas of technology incidental to rocketry and manned spaceflight, including avionics, telecommunications, computers; the Apollo program was conceived during the Eisenhower administration in early 1960, as a follow-up to Project Mercury. While the Mercury capsule could only support one astronaut on a limited Earth orbital mission, Apollo would carry three astronauts.
Possible missions included ferrying crews to a space station, circumlunar flights, eventual manned lunar landings. The program was named after Apollo, the Greek god of light and the sun, by NASA manager Abe Silverstein, who said that "I was naming the spacecraft like I'd name my baby." Silverstein chose the name at home one evening, early in 1960, because he felt "Apollo riding his chariot across the Sun was appropriate to the grand scale of the proposed program."In July 1960, NASA Deputy Administrator Hugh L. Dryden announced the Apollo program to industry representatives at a series of Space Task Group conferences. Preliminary specifications were laid out for a spacecraft with a mission module cabin separate from the command module, a propulsion and equipment module. On August 30, a feasibility study competition was announced, on October 25, three study contracts were awarded to General Dynamics/Convair, General Electric, the Glenn L. Martin Company. Meanwhile, NASA performed its own in-house spacecraft design studies led by Maxime Faget, to serve as a gauge to judge and monitor the three industry designs.
In November 1960, John F. Kennedy was elected president after a campaign that promised American superiority over the Soviet Union in the fields of space exploration and missile defense. Up to the election of 1960, Kennedy had been speaking out against the "missile gap" that he and many other senators felt had developed between the Soviet Union and United States due to the inaction of President Eisenhower. Beyond military power, Kennedy used aerospace technology as a symbol of national prestige, pledging to make the US not "first but, first and, first if, but first period." Despite Kennedy's rhetoric, he did not come to a decision on the status of the Apollo program once he became president. He knew little about the technical details of the space program, was put off by the massive financial commitment required by a manned Moon landing; when Kennedy's newly appointed NASA Administrator James E. Webb requested a 30 percent budget increase for his agency, Kennedy supported an acceleration of NASA's large booster program but deferred a decision on the broader issue.
On April 12, 1961, Soviet cosmonaut Yuri Gagarin became the first person to fly in space, reinforcing American fears about being left behind in a technological competition with the Soviet Union. At a meeting of the US House Committee on Science and Astronaut