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3 A Brief History of Space Flight
Young, Thomas P. Stafford and Eugene A. Cernan by the Apollo-10 were launched
on May 18, 1969, to carry out the flight test mission of encompassing all aspects of an
actual crewed lunar landing, except for the landing. As the Apollo-10 was accelerated
to the second cosmic velocity by the S-IVB stage of the Saturn V rocket, and it entered
the Earth-Moon transfer orbit, the CSM was separated from the S-IVB rocket with
an ejection mode, and turned 180 degrees to dock to the LM which was exposed
by jettisoning the S-IVB shell. The recombined Apollo-10 turned again and flew to
the Moon along the Earth-Moon transfer orbit, with a flight distance of 399,200 km.
When the Apollo-10 entered into the lunar parking-orbit by the brake engine ignition,
Young stayed in the CSM and continued to fly around the Moon while by using the
descent engine, Stafford and Cernan in the LM was slowly descending toward the
lunar surface. At an altitude of 15.2 km away from the lunar surface, they jettisoned
the descent stage, and then returned to the lunar parking-orbit by using the ascent
engines to dock to the CSM. As Stafford and Cernan returned to the CM, the ascent
stage was separated from the CSM, and finally three astronauts returned to the Earth
safely.
In order to ensure the successful implementation of the manned lunar landing
program, the NASA had also carried out four auxiliary projects. Firstly, the Ranger
Program was a series of unmanned space missions by NASA between 1961 and
1965, launched a total of nine vehicles, whose objective was to take the close-up
images of the surface of the Moon and argue the feasibility of the crewed-craft
landing on the Moon. Secondly, the Gemini Program was the NASA’s second human
spaceflight project, which was a bridge between the Project Mercury and the Apollo
Program. A total of ten spaceships with two-astronaut crew each were launched
successively between 1965 and 1966, to carry out a series of space experiments, such
as biomedical research, maneuvering flight, rendezvous and docking, and extravehicular activity. Thirdly, the Lunar Orbiter Program was a series of five unmanned
lunar orbiter missions launched by the NASA from 1966 to 1967. Intended to help
select Apollo landing sites by mapping the lunar surface, they provided the first
photographs from lunar orbit and photographed both the Earth and Moon. Fourthly,
the Surveyor Program was a NASA project from 1964 to 1968, sent seven robotic
vehicles to the lunar surface, whose primary goal was to demonstrate the feasibility
of soft landing on the Moon. The capability of the spacecrafts to make midcourse
corrections was demonstrated, and the Landers carried instruments to help evaluate
the suitability of their landing sites for manned Apollo landings. Moreover, several
Surveyor spacecrafts had robotic shovels designed to test lunar soil mechanics, and
conducted to make the in-situ detection on the lunar surface and to investigate the
physical and chemical properties of the lunar soil.
The Apollo flight tests and its auxiliary project missions were all successful, and
the entire process of landing on the Moon was comprehensively practiced, so the
NASA decided to carry out the mission of manned landing on the Moon, whose
specific tasks are to achieve the astronauts landing on the surface of the Moon and
safe-returning to the Earth, and to complete the investigation and sampling of the
lunar surface. On July 16, 1969, the Apollo-11 spacecraft was put into orbit by the
Saturn V rocket at the launch pad 39Aof the Kennedy Sapce Center. Three astronauts
3 A Brief History of Space Flight
Young, Thomas P. Stafford and Eugene A. Cernan by the Apollo-10 were launched
on May 18, 1969, to carry out the flight test mission of encompassing all aspects of an
actual crewed lunar landing, except for the landing. As the Apollo-10 was accelerated
to the second cosmic velocity by the S-IVB stage of the Saturn V rocket, and it entered
the Earth-Moon transfer orbit, the CSM was separated from the S-IVB rocket with
an ejection mode, and turned 180 degrees to dock to the LM which was exposed
by jettisoning the S-IVB shell. The recombined Apollo-10 turned again and flew to
the Moon along the Earth-Moon transfer orbit, with a flight distance of 399,200 km.
When the Apollo-10 entered into the lunar parking-orbit by the brake engine ignition,
Young stayed in the CSM and continued to fly around the Moon while by using the
descent engine, Stafford and Cernan in the LM was slowly descending toward the
lunar surface. At an altitude of 15.2 km away from the lunar surface, they jettisoned
the descent stage, and then returned to the lunar parking-orbit by using the ascent
engines to dock to the CSM. As Stafford and Cernan returned to the CM, the ascent
stage was separated from the CSM, and finally three astronauts returned to the Earth
safely.
In order to ensure the successful implementation of the manned lunar landing
program, the NASA had also carried out four auxiliary projects. Firstly, the Ranger
Program was a series of unmanned space missions by NASA between 1961 and
1965, launched a total of nine vehicles, whose objective was to take the close-up
images of the surface of the Moon and argue the feasibility of the crewed-craft
landing on the Moon. Secondly, the Gemini Program was the NASA’s second human
spaceflight project, which was a bridge between the Project Mercury and the Apollo
Program. A total of ten spaceships with two-astronaut crew each were launched
successively between 1965 and 1966, to carry out a series of space experiments, such
as biomedical research, maneuvering flight, rendezvous and docking, and extravehicular activity. Thirdly, the Lunar Orbiter Program was a series of five unmanned
lunar orbiter missions launched by the NASA from 1966 to 1967. Intended to help
select Apollo landing sites by mapping the lunar surface, they provided the first
photographs from lunar orbit and photographed both the Earth and Moon. Fourthly,
the Surveyor Program was a NASA project from 1964 to 1968, sent seven robotic
vehicles to the lunar surface, whose primary goal was to demonstrate the feasibility
of soft landing on the Moon. The capability of the spacecrafts to make midcourse
corrections was demonstrated, and the Landers carried instruments to help evaluate
the suitability of their landing sites for manned Apollo landings. Moreover, several
Surveyor spacecrafts had robotic shovels designed to test lunar soil mechanics, and
conducted to make the in-situ detection on the lunar surface and to investigate the
physical and chemical properties of the lunar soil.
The Apollo flight tests and its auxiliary project missions were all successful, and
the entire process of landing on the Moon was comprehensively practiced, so the
NASA decided to carry out the mission of manned landing on the Moon, whose
specific tasks are to achieve the astronauts landing on the surface of the Moon and
safe-returning to the Earth, and to complete the investigation and sampling of the
lunar surface. On July 16, 1969, the Apollo-11 spacecraft was put into orbit by the
Saturn V rocket at the launch pad 39Aof the Kennedy Sapce Center. Three astronauts