|Primary goal||First man in space|
|Achievements||US manned flight firsts:|
|Rockets||Little Joe, Redstone, Atlas D|
|Followers||Gemini and Apollo|
|Rival||Vostok program (Soviet)|
United States Project Mercury was the second human spaceflight program of the world. It ran from 1959 through 1963 with two goals: putting a human in orbit around the Earth, and doing it before the Soviet Union, as part of the early space race. It succeeded in the first but not the second: in the first Mercury mission on 5 May 1961, Alan Shepard became the first American in space; however the Soviet Union had put Yuri Gagarin into space (and also into orbit) one month earlier. John Glenn became the first American to reach orbit on February 20, 1962, during the third manned Mercury flight. Glenn was the third person to reach orbit, following Gagarin and Gherman Titov.
The program included 20 unmanned launches, followed by two suborbital and four orbital flights with astronaut pilots. Early planning and research were carried out by the National Advisory Committee for Aeronautics (NACA), but the program was officially conducted by its successor organization, NASA. It also absorbed the USAF program Man In Space Soonest which had had the same objectives. Mercury laid the groundwork for Project Gemini and the follow-on Apollo moon-landing program.
The project name came from Mercury, a Roman god often seen as a symbol of speed. Mercury is also the name of the innermost planet of the Solar System, which moves faster than any other and hence conveys an image of speed, although Project Mercury had no other connection to the planet.
Goals and guidelines 
The goals of the program were to orbit a manned spacecraft around Earth, investigate the pilot's ability to function in space and to recover both pilot and spacecraft safely. NASA also established program guidelines: existing technology and off-the-shelf equipment should be used wherever practical, the simplest and most reliable approach to system design would be followed, an existing launch vehicle would be employed to place the spacecraft into orbit, and a progressive and logical test program would be used..
Spacecraft requirements included: a reliable launch escape system to separate the spacecraft and its occupant from the launch vehicle in case of impending failure; manual attitude control by the pilot; a reliable retrorocket system to bring the spacecraft out of orbit; a zero-lift, drag braking blunt body for atmospheric reentry; and landing on water.
On 29 December 1958 North American Aviation was awarded a contract to design and build Little Joe launch vehicles to be used for altitude flight testing of the Mercury launch escape system. Twelve companies bid to build the Mercury spacecraft, an unusually high number for a $20 million contract, given the project's great prestige. In January 1959 McDonnell Aircraft Corporation was chosen to be prime contractor for the spacecraft, and the contract for 12 spacecraft was awarded in February.
In May 1959 North American Aviation delivered the first two Little Joes, and in June, an Atlas D launch vehicle named Big Joe was delivered, for use in a suborbital heat shield test flight. In July, the planned use of the Jupiter rocket as a suborbital launch vehicle was changed to the Redstone. In October General Electric delivered to McDonnell the ablative heat shield designated for installation on the first Mercury spacecraft. In December the launch vehicle for Mercury-Redstone 1 was ready to begin static tests installed on a test stand at ABMA.
In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was more than $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12, Christopher C. Kraft, Jr. was appointed to head the Mercury operations coordination group. In April, the first spacecraft was delivered to Wallops Island for the beach-abort test. The test was completed successfully on May 9.
Because of their small size, it was said that the Mercury spacecraft were worn, not ridden. With 60 cubic feet (1.7 m3) of habitable volume, the spacecraft was just large enough for the single crew member. Inside were 120 controls: 55 electrical switches, 30 fuses and 35 mechanical levers.[unreliable source] The spacecraft was designed by Max Faget and NASA's Space Task Group.:26–28
Despite the astronauts' test pilot experience, NASA at first envisioned them as "minor participants" during their flights, causing many conflicts between the astronauts and engineers during the spacecraft's design. Nonetheless, contrary to other reports, the project's leaders always intended for pilots to be able to control their spacecraft, as they valued humans' ability to contribute to missions' success.:23–25[contradiction] John Glenn's manual attitude adjustments during the first orbital flight were an example of the value of such control.:33 The astronauts requested—and received—a larger window and manual reentry controls.:24–25
Production summary 
NASA ordered 20 production spacecraft, numbered 1 through 20, from McDonnell Aircraft, St. Louis, Missouri. Five of the 20, Nos. 10, 12, 15, 17, and 19, were not flown. Spacecraft No. 3 and No. 4 were destroyed during unmanned test flights. Spacecraft No. 11 sank and was recovered from the bottom of the Atlantic Ocean after 38 years. Some spacecraft were modified after initial production (refurbished after launch abort, modified for longer missions, etc.) and received a letter designation after their number, examples 2B, 15B. Some spacecraft were modified twice; for example, spacecraft 15 became 15A and then 15B.
A number of Mercury boilerplate spacecraft (including mockup/prototype/replica spacecraft, made from non-flight materials or lacking production spacecraft systems and/or hardware) were also made by NASA and McDonnell Aircraft. They were designed and used to test spacecraft recovery systems, and escape tower and rocket motors. Formal tests were done on test pad at Langley and at Wallops Island using the Little Joe and Big Joe rockets.
Launch vehicles 
The Mercury program used three launch vehicles::28–30
- Little Joe (height: 55 ft) – for launch escape system tests at altitude. Eight unmanned flights were made, two of which carried live monkeys. It was a solid-fuel rocket designed specially for Project Mercury and theoretically able to carry a spacecraft to an altitude of 100 miles (161 km) on a ballistic curve. Together with a Mercury boilerplate it was used to test the escape tower and abort procedures.
- Mercury-Redstone Launch Vehicle (height 83 ft) – 1-stage rocket for suborbital (ballistic) flights. Four unmanned flights were made, one of which carried a chimpanzee named Ham. After that it was used for the first two manned flights. The Jupiter rocket was originally considered for the suborbital launch vehicle, but was replaced by the Redstone in July 1959 due to budget constraints.
- Atlas LV-3B (height 94 ft) – 2-stage rocket for orbital manned flight. Six unmanned test flights were made, four suborbital and two orbital one of which carried a chimpanzee. After that it was used for four manned orbital flights. The Atlas D rocket required extra strengthening in order to handle the increased weight of the Mercury spacecraft beyond that of the nuclear warheads they were designed to carry.
The Titan missile was also considered for use for later Mercury missions; however, the Mercury program was terminated before these missions were flown. Instead, the Titan was used for the Gemini program which followed Mercury. The Mercury program also used a Scout rocket for a single flight, Mercury-Scout 1, which was intended to launch a small satellite designed to evaluate the worldwide Mercury Tracking Network. Launched on November 1, 1961, however, the rocket was destroyed by the Range Safety Officer after 44 seconds of flight.
Mission profile 
There were two kinds of missions: suborbital and orbital. In the suborbital flight, the spacecraft went directly from launch to re-entry at the highest point; in the orbital mission the craft went into an orbit around the Earth. To achieve the latter a higher speed and altitude and therefore bigger rocket was needed. The altitude for suborbital missions were 117 miles (188 km) and for orbital missions 156 miles (251 km).
During the launch phase of the mission, the Mercury spacecraft and astronaut were protected from launch vehicle failures by the Launch Escape System. The LES consisted of a solid fuel, 52,000 lbf (231 kN) thrust rocket with three engine bells mounted on a tower above the spacecraft.:28 In the event of a launch abort, the LES would fire for one second, pulling the spacecraft and astronaut away from the launch vehicle and a possible explosion. The spacecraft would then descend on its parachute recovery system. After booster engine cutoff (BECO, point B), the LES was no longer needed and was separated from the spacecraft by a solid fuel, 800 lbf (3.6 kN) thrust jettison rocket that fired for 1.5 seconds (point C).
After a successful liftoff, the spacecraft fired three small clustered solid-fuel, 400 lbf (1.8 kN) thrust rockets for 1 second to separate the spacecraft from the launch vehicle. These rockets were called the posigrade rockets:28 (point D on illustration). Once the spacecraft separated from the launch vehicle, no in-flight change of orbit was possible, except to initiate reentry.
The spacecraft was equipped with a thruster attitude control system, consisting of three sets of high and low powered automatic control jets and separate manual jets, one for each axis (roll, pitch, and yaw), supplied from two separate hydrogen peroxide fuel tanks, one automatic and one manual. The pilot could select any one of the three thruster systems and either of the two fuel tanks in flight. The spacecraft was also designed to be completely controllable from the ground in the event that something impaired the pilot's ability to function.
The spacecraft had three solid-fuel, 1000 lbf (4.5 kN) thrust retrorockets that fired for 10 seconds each:28 (point F on illustration). One was sufficient to return the spacecraft to Earth if the other two failed. The firing sequence (known as ripple firing) required firing the first retro, followed by the second retro five seconds later (while the first was still firing). Five seconds after that, the third retro fired (while the second retro was still firing).
There was a small hinged metal flap at the nose of the spacecraft called the spoiler. If the spacecraft started to reenter nose first (another stable reentry attitude for the spacecraft), airflow over the spoiler would flip the spacecraft around to the proper, heatshield-first reentry attitude, a technique called shuttlecocking. During reentry (point G), the astronaut would experience about 8 g-forces on an orbital mission, and 11–12 gs on a suborbital mission.
Design of the spacecraft called for the use of either a beryllium or ablative fiberglass heat shield to protect it from the effects of aerodynamic heating on reentry. Beryllium, fairly expensive and produced in sufficient quantities only by a single U.S. company, was used for the suborbital version of the capsule. The ablative shield, composed of an aluminum honeycomb structure covered with multiple layers of fiberglass, was used on the orbital capsules. As the temperature rose to 2,000 °F (1,100 °C) the fiberglass layers would evaporate and take the heat with it. The spacecraft would become hot, but not harmfully so.
After re-entry, a small, drogue parachute (point H) was deployed at 21,000 ft (6.4 km) for first lowering of speed. The main parachute (point I) was deployed at 10,000 ft (3 km), further slowing the spacecraft in preparation for landing. Just before hitting the water, a landing bag inflated from behind the heat shield to reduce the force of impact. Upon landing, additional bags inflated around the nose of the craft to keep the capsule upright in the water, and the parachutes were released. Once the recovery helicopter hooked onto the spacecraft, the astronaut blew the escape hatch to exit the capsule. It was also possible to exit the capsule through the nose cone.
Space race 
On October 4, 1957, the United States' Cold War adversary, the Soviet Union (USSR), beat the US in orbiting the first artificial satellite Sputnik 1, starting what became known as a "Space Race". The next major goal was to put a human pilot into orbit around the Earth, which became the US Project Mercury. The USSR beat the US again in reaching this goal, by launching Yuri Gagarin in a single orbit aboard Vostok 1 in April 1961. The United States referred to their space pilots as astronauts, while the Soviets referred to their pilots as cosmonauts.
One month after Gagarin's flight, Alan Shepard became the first Mercury astronaut to fly in space, aboard a capsule he named Freedom 7 on a ballistic flight to a landing in the Atlantic ocean. John Glenn, the third Mercury astronaut to fly, became the first American to reach orbit aboard Friendship 7 on February 20, 1962, during the third manned Mercury flight, but only after the Soviets had launched a second cosmonaut, Gherman Titov, into orbit. Three more Mercury orbital flights were made, ending in 1963.
Two suborbital flights were cancelled; they began to look embarrassing after the Soviet Union had made a day-long orbital flight in August 1961. Three orbital flights were also cancelled since it was clear that the spacecraft had reached its limits. At the last flight the batteries were exhausted before reentry, but the spacecraft landed safely.
The USA had lost the first round of the Space Race to the Soviets; however, the FAI rules in 1961 required that a pilot must land safely with the spacecraft for the flight to be considered an official spaceflight.:283 In reality, Gagarin landed separately by parachute while the space craft crashed to the ground, but the Soviet Union did not admit this until 1971.:283[a] Although the FAI initially refused to recognize Gagarin's pioneering flight, it subsequently amended its position to recognize (as the FAI website states) that he was the "first human being to journey into outer space".
The first Americans to venture into space were drawn from a group of 110 military pilots chosen for their flight test experience and because they met certain physical requirements. NASA announced the selection of seven of these – known as the Mercury Seven – as astronauts on 9 April 1959, though only six of the seven flew Mercury missions, after Slayton was grounded due to a heart condition. In order of flight:
- Alan Bartlett Shepard, Jr., USN (1923–1998); first American in space, May 1961
- Virgil Ivan "Gus" Grissom, USAF (1926–1967); flew 21 July 1961. Died 1967 during Apollo 1 pre-launch test
- John Herschel Glenn, Jr., USMC (born 1921); first American to orbit the Earth, 20 February 1962
- Malcolm Scott Carpenter, USN (born 1925), flew 24 May 1962
- Walter Marty "Wally" Schirra, Jr., USN (1923–2007), flew 3 October 1962
- Leroy Gordon "Gordo" Cooper, Jr., USAF (1927–2004), flew 15 May 1963
- Donald Kent "Deke" Slayton, USAF (1924–1993); grounded in 1962, but reinstated in 1972 and flew on the Apollo-Soyuz Test Project in 1975.
Training and model testing 
Just like the rockets and spacecraft were tested in details by unmanned flights, the astronauts went through a training program in special facilities and model arrangements. Some tests were made to see their response to weightlessness on the one hand and high g forces on the other. Other parts of the training were meant to give them practice in maneuvering the spacecraft and get in and out of its narrow openings wearing a space suit. Together with this, the aerodynamics of the spacecraft and its heat shield were tested in wind tunnels.
Maneuvre practice in gimbaling rig
Full scale model for wind tunnel tests, (Planes of Fame Air Museum, Chino, California)
Tracking network 
Six manned Mercury missions were made, all controlled from the Mercury Control Center near the launch site. To track the manned orbit missions a network of radio stations was built around the equator. Two other tracking networks already existed: one for unmanned missions and one for deep space missions, however they were not adequate for manned missions.
Deep space missions require a few big telescopes whereas Earth orbit manned missions require many small radiostations at points that the spacecraft will pass over on its way. Unmanned missions need the same kind of radio stations but in smaller number. These differences led NASA to build an independent network for the manned missions. Apart from the U.S. there were tracking stations in Australia and Africa together with stations on ships in the oceans around the equator.
Launch personnel 
T.J. O'Malley pushed the button to launch Glenn. Site Manager and Launch Conductor for General Dynamics Astronautics at Complex 14 on the Atlantic Missile Range, Calvin D. Fowler, pushed the button to launch Carpenter, Schirra and Cooper, the last three manned Atlas launches, becoming the person who "now has launched more men into space than any other man in the free world".
"M" in the start of a mission name stands for Mercury. Names of launch vehicles can be read from mission names; MR=Redstone, MA=Atlas, MJ=Jupiter, MS=Scout and LJ=Little Joe. Times are in UTC.
Manned flights 
Beginning with Alan Shepard's Freedom 7 flight, the astronauts named their own spacecraft, and all added "7" to the name or callsign to acknowledge the teamwork of they and their fellow astronauts. Redstone and Atlas rockets had been tested by unmanned flight. This is the reason why the first manned mission with a Redstone rocket has the number 3 (MR-3) and the first with an Atlas rocket is MA-6.
Unmanned flights 
The program included 20 robotic launches for development and testing of equipment. Not all of these were intended to reach space and not all were successful in completing their objectives. Four of the flights included animals as test pilots starting with the fifth flight in 1959. All animals returned safely. Launch vehicles not following naming rule: Big Joe 1 was launched by an Atlas rocket and Beach Abort was a test of the launch escape system from the ground.
|Mission||Date||Time||Duration||Remarks||Big Joe and Ham|
|LJ-1||21 August 1959||N/A||20 s||Test of launch escape system during flight.|
|Big Joe 1||9 September 1959||N/A||13 m 00 s||Test of heat shield and Atlas / spacecraft interface|
|LJ-6||4 October 1959||N/A||5 m 10 s||Test of spacecraft aerodynamics and integrity|
|LJ-1A||4 November 1959||N/A||8 m 11 s||Test of launch escape system during flight|
|LJ-2||4 December 1959||N/A||11 m 6 s||Carried Sam, a rhesus macaque, to 85 kilometres in altitude|
|LJ-1B||21 January 1960||N/A||8 m 35 s||Carried Miss Sam to 9.3 statute miles (15 kilometres) in altitude|
|Beach Abort||9 May 1960||N/A||1 m 31 s||Test of the off-the-pad abort system|
|MA-1||29 July 1960||13:13||3 m 18 s||First flight of Mercury / Atlas|
|LJ-5||8 November 1960||N/A||2 m 22 s||First flight of a production Mercury spacecraft|
|MR-1||21 November 1960||N/A||2 s||Launched 4 inches (100 mm); settled back on pad due to electrical malfunction|
|MR-1A||19 December 1960||N/A||15 m 45 s||First flight of Mercury / Redstone|
|MR-2||31 January 1961||16:55||16 m 39 s||Carried the chimpanzee Ham on suborbital flight|
|MA-2||21 February 1961||14:10||17 m 56 s||Unmanned test|
|LJ-5A||18 March 1961||N/A||23 m 48 s||Test of the launch escape system during the most severe conditions of a launch|
|MR-BD||24 March 1961||17:30||8 m 23 s||Redstone development test flight|
|MA-3||25 April 1961||16:15||7 m 19 s||Contained "robot astronaut"|
|LJ-5B||28 April 1961||N/A||5 m 25 s||Test of the launch escape system during the most severe conditions of a launch|
|MA-4||13 September 1961||14:09||1 h 49 m 20 s||Unmanned test, completed one orbit|
|MS-1||1 November 1961||15:32||44 s||Test of Mercury tracking network|
|MA-5||29 November 1961||15:08||3 h 20 m 59 s||Carried the chimpanzee Enos on a two-orbit flight|
Canceled flights 
Apart from the listed missions, ballon ascents were intended to study high altitude conditions. These were cancelled on May 22, 1959 and replaced with experiments at the Lewis Research Center altitude wind tunnel facilities.
|Mission||Callsign||Pilot||Planned Launch Date||Cancellation Date||Remarks|
|MJ-1||N/A||N/A||N/A||July 1, 1959||Proposed heat shield test.|
|MJ-2||N/A||chimpanzee||First Quarter, 1960||July 1, 1959||Proposed maximum dynamic pressure qualifying test for a capsule.|
|MR-5||N/A||Glenn (likely)||August 1961|
|MR-6||N/A||July 1961||Deemed unnecessary.|
|MA-10||Freedom 7-II||Shepard||October 1963||June 13, 1963||Intended to be a three-day mission.|
|MA-11||N/A||Grissom||Fourth Quarter, 1963||October 1962||Intended to be a one-day mission.|
|MA-12||N/A||Schirra||Fourth Quarter, 1963||October 1962||Intended to be a one-day mission.|
Splashdown sites 
All of the Mercury spacecraft landed in the Atlantic Ocean east of Florida, except for the final two, which landed in the Pacific.
|Spacecraft||Landing Date||Location||Recovery Ship||Miss (km)||Ref.||USS Kearsarge with crew spelling Mercury-9|
|Jupiter AM-18||28 May 1959||48–96 km N of Antigua Is||USS Kiowa (ATF-72)||16|||
|Mercury-Big Joe||9 September 1959||2,407 km SE of Cape Canaveral||USS Strong (DD-758)||925|||
|Mercury-Little Joe 2||4 December 1959||319 km SE of Wallops Is, VA||USS Borie (DD-704)||N/A|||
|Mercury-Redstone 1A||19 December 1960||378 km SE of Cape Canaveral||USS Valley Forge (CV-45)||12.9|||
|Mercury-Redstone 2||31 January 1961||676 km SE of Cape Canaveral||USS Donner (LSD-20)||209.2|||
|Mercury-Atlas 2||21 February 1961||2,293 km SE of Cape Canaveral||USS Donner (LSD-20)||20.9|||
|Mercury-Atlas 4||13 September 1961||258 km E of Bermuda||USS Decatur (DD-936)||64.4|||
|Mercury-Atlas 5||29 November 1961||805 km SE of Bermuda||USS Stormes (DD-780)||N/A|||
|Freedom 7||5 May 1961||USS Lake Champlain (CVS-39)||5.6|||
|Liberty Bell 7||21 July 1961||USS Randolph (CVS-15)||9.3|||
|Friendship 7||20 February 1962||USS Noa (DD-841)||74|||
|Aurora 7||24 May 1962||USS Farragut (DLG-6)||400|||
|Sigma 7||3 October 1962||USS Kearsarge (CVS-33)||7.4|||
|Faith 7||16 May 1963||USS Kearsarge (CVS-33)||8.1|||
Program cost 
In January 1969, NASA prepared for the US Congress an estimate of the costs for projects Mercury, Gemini, and Apollo (to the first manned Moon landing). This estimate gave the cost of Project Mercury as $392.6 million, broken down as follows:
- Spacecraft: $135.3 million
- Launch vehicles: $82.9 million
- Operations: $49.3 million
- Tracking operations and equipment: $71.9 million
- Facilities: $53.2 million
Flight patches that purport to be patches from various Mercury missions are available to the public. In reality, these patches were designed by private entrepreneurs several years after the Mercury program. When mission patches were created by crews in the Gemini program, this caused a public demand for Mercury flight patches, which was filled by these entrepreneurs. The only patches the Mercury astronauts wore, however, were the NASA logo and a name tag. Each manned Mercury spacecraft was decorated with a flight insignia featuring the spacecraft name (Freedom 7, etc.).
The Right Stuff is a 1983 American film about Project Mercury, adapted from Tom Wolfe's 1979 book by the same name. It also deals with the test pilots who were involved in high-speed aeronautical research that preceded the project.
In 1962, the US Post Office honored the Mercury-Atlas 6 flight with the Project Mercury commemorative stamp, the first U.S. postal issue to depict a manned spacecraft. The stamp first went on sale in Cape Canaveral, Florida on 20 February 1962, the same day as the Project Mercury launch putting the first U.S. astronaut into orbit. On 4 May 2011, the US Postal Service released a stamp commemorating the 50th anniversary of the 5 May 1961 flight of Freedom 7 (which carried Alan Shepard into space).
On 25 February 2011, the Institute of Electrical and Electronic Engineers, the world's largest technical professional society, awarded Boeing Company (successor to McDonnell Aircraft and McDonnell Douglas) a Milestone Award for important inventions which debuted on the Mercury spacecraft. The IEEE bestows this honor on projects that were accomplished at least 25 years in the past. Boeing received the award in recognition of Project Mercury's pioneering "navigation and control instruments, autopilot, rate stabilization and control, and fly-by-wire systems."
See also 
- Spaceflight portal
- Media related to Mercury program at Wikimedia Commons
- Mercury 13 (About the 13 American women who, as part of a privately funded program, underwent and passed the same Phase I physical examinations that the Lovelace Foundation had developed as part of NASA’s astronaut selection process.)
- The first Soviet spacecraft to make a soft landing was Voskhod 1 in October 1964. It was made possible by a parachute combined with rockets suspended above the capsule in lines. The rockets ignited just before the spacecraft touched the ground to slow it down the last bit.
- "Mercury Manned Flights Summary". NASA. Retrieved 2011-10-09.
- "NASA history, Gagarin". NASA. Retrieved 2011-10-09.
- "NASA, John Glenn". NASA. Retrieved 2011-10-09.
- "Major Events Leading to Project Mercury". NASA.
- Prepared by James M. Grimwood. "Research and Development Phase of Project Mercury". NASA MSC.
- Cheryl L. Mansfield. "In Their Footsteps: The Mercury 7". NASA.
- "Project Mercury". U.S. Centennial of Flight Commission.
- "Project Mercury". NASA Public Affairs Office.
- "Mercury Goals and Guidelines". NASA Public Affairs Office.
- "Little Joe Launch Vehicle". Boeing.
- Bello, Francis (1959). "The Early Space Age". Fortune. Retrieved June 5, 2012.
- "Mercury-Jupiter 2 (MJ-2)". Encyclopedia Astronautica.
- "Chronology – Quarter 1 1960". Encyclopedia Astronautica.
- "Christopher C Kraft, Jr American Manager. Born 1924.". Encyclopedia Astronautica.
- "PART II (B), Research and Development Phase of Project Mercury, January 1960 through 5 May 1961". NASA.
- "Project Mercury". U.S Centennial of flight commission.
- "Biographical Data, Dr. Maxime A. Faget". NASA.
- Logsdon, John M. with Roger D. Launius (editors) Exploring the Unknown: Selected Documents in the History of the U.S. Civil Space Program / Volume VII Human Spaceflight: Projects Mercury, Gemini, and Apollo The NASA History Series, 2008.
- "Appendix 6 – Location of Mercury Spacecraft, and Exhibit Schedule". NASA.
- "Liberty Bell 7 capsule raised from ocean floor". CNN.
- "Mercury MA-10". Encyclopedia Astronautica.
- "Boilerplate Mercury Capsule". NASA.
- "Mercury". Encyclopedia Astronautica.
- NASA Mercury History Sections #44 and #47
- "Mercury Boilerplate Tests". Astronautix.com. Retrieved 2010-12-10.
- "MA-2: Trussed Atlas Qualifies the Capsule". NASA.
- "More Than a Spacecraft". NASA.
- "Mercury Scout 1". NASA.
- NASA, Mercury-Redstone 3 (18), retrieved 2011-10-14
- "Atlas Mercury manual, page 4". NASA. Retrieved 2011-10-02.
- FamiliarizationManual p 2-16
- "How Project Mercury Worked". How Stuff Works. Retrieved 2011-10-04.
- Walter A. McDougall "Shooting the Moon," American Heritage, Winter 2010.
- "Mercury". Encyclopedia Astronautica. Retrieved 2011-10-09.
- Siddiqi, Asif A.. Challenge To Apollo: The Soviet Union and the Space Race, 1945-1974. NASA.
- Astronautix Voskhod 1
- "History of Manned Space Flight - Part 1: The Pioneers". FAI. Retrieved 2012-06-23.
- "Alan B. Shepard, Jr.". NASA.
- "The 40th Anniversary of the Mercury Seven". NASA.
- "APOLLO-SOYUZ". NASA.
- Press release for Gordon Cooper's Mercury Atlas launch on May 15, 1963
- "Sam the Monkey After His Ride in the Little Joe 2 Spacecraft". NASA.
- "Project Mercury - A Chronology. Part 2 (A)". History.nasa.gov. Retrieved 2012-05-24.
- "Mercury-Jupiter 2 (MJ-2)". Astronautix.com. Retrieved 2012-05-24.
- Slayton, Donald K. "Deke"; Cassutt, Michael (1994). Deke! U.S. Manned Space: From Mercury to the Shuttle (1st ed.). New York: Forge (St. Martin's Press). p. 104. ISBN 0-312-85503-6. LCCN 94-2463. OCLC 29845663.
- Slayton, Donald K. "Deke"; Cassutt, Michael (1994). Deke! U.S. Manned Space: From Mercury to the Shuttle (1st ed.). New York: Forge (St. Martin's Press). p. 101. ISBN 0-312-85503-6. LCCN 94-2463. OCLC 29845663.
- "Kiowa". History.navy.mil. Retrieved 2012-05-24.
- "Animals Survive 1,500-Mile Ride In Rocket Nose", Windsor, ON Canada - Daily Star newspaper May 28, 1959
- "Big Joe Shot", This New Ocean:A History of Project Mercury,Chapter 7, (NASA SP-4201)
- "Monkey Completes Long Flight Aloft", Ellensburg, WA - Daily Record newspaper, Dec 4, 1959
- "Man-In-Space Capsule To Be Closely Studied", Florence, Alabama - Times newspaper, Dec 20, 1960
- USS Donner Memorial Association
- "Chimp Survives Space Shot", Milwaukee Sentinel newspaper, Feb 1, 1961
- "USS Donner LSD20". Homestead.com. Retrieved 2012-05-24.
- "Space Capsule Soars 107 Miles High", Florence, Alabama - Times newspaper, Feb 21, 1961
- "U.S. Orbited, Returned", Meriden, CT - Journal newspaper, Sep 13, 1961
- "Capsule Trouble Forces Early Landing Of Craft", Toledo, Ohio - Blade newspaper, Nov 29, 1961
- "Mercury-Redstone 3 Landing Point", NASA Historical Data Book, Volume II, Programs and Projects 1958-1968; Pg 143, Table 2-30, Landing Point, (NASA SP-4012)
- "Mercury-Redstone 4 Landing Point", NASA Historical Data Book, Volume II, Programs and Projects 1958-1968; Pg 144, Table 2-31, Landing Point, (NASA SP-4012)
- "Mercury-Atlas 6 Landing Point", NASA Historical Data Book, Volume II, Programs and Projects 1958-1968; Pg 145, Table 2-32, Landing Point, (NASA SP-4012)
- "Mercury-Atlas 7 Landing Point", NASA Historical Data Book, Volume II, Programs and Projects 1958-1968; Pg 146, Table 2-33, Landing Point, (NASA SP-4012)
- "Mercury-Atlas 8 Landing Point", NASA Historical Data Book, Volume II, Programs and Projects 1958-1968; Pg 147, Table 2-34, Landing Point, (NASA SP-4012)
- "Mercury-Atlas 9 Landing Point", NASA Historical Data Book, Volume II, Programs and Projects 1958-1968; Pg 148, Table 2-35, Landing Point, (NASA SP-4012)
- Wilford, John Noble (July 1969). We Reach the Moon. New York: Bantam Books. p. 67.
- Lafleur, Claude (2010-03-08). "Costs of US piloted programs". The Space Review. Retrieved February 18, 2012.
- "The Right Stuff". IMdB. Retrieved 2011-10-04.
- Mystic stamp company, retrieved 1 April 2012
- "Stamps Mark Shepard's 1961 Flight". US Postal Service. Retrieved 5 May 2011.
- Boeing Press Release, 25 February 2011
Further reading 
- Chris Kraft, Flight: My Life in Mission Control (March 2001). Hardcover, 371 pages, ISBN 0-525-94571-7 or paperback (2002) ISBN 0-452-28304-3.
- Gene Kranz, Failure is Not an Option. Factual, from the standpoint of a chief flight controller. ISBN 0-7432-0079-9
- Schirra, Grissom, Glenn, Slayton, Shepherd, Carpenter, Cooper, We Seven. (ISBN B00005X54G); Simon & Schuster – 1962. A collection of articles written by the seven Mercury astronauts.
- Francis French and Colin Burgess, Into That Silent Sea:Trailblazers of the Space Era 1961–1965. ISBN 978-0-8032-1146-9. First-hand interviews of Project Mercury participants.
- The Mercury Project (Kennedy Space Center)
- Space Medicine In Project Mercury By Mae Mills Link
- Project Mercury Simulator for Mac and PC
- Chronology of Project Mercury – NASA report (PDF format)
- This New Ocean: A History of Project Mercury – NASA report
- Project Mercury familiarization manual (PDF) November 1961
- The Mercury Redstone Project (PDF) December 1964
- Results of the first US manned orbital space flight – Feb 20, 1962 (Friendship 7) NASA report – (PDF format)
- Results of the second US manned orbital space flight, May 24, 1962 (Aurora 7) NASA report – (PDF format)
- PDFs of historical Mercury documents including familiarization manuals.
- Project Mercury Drawings and Technical Diagrams
- Project Mercury - 1963 NASA Space Program Documentary (Video)