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3 A Brief History of Space Flight
October 1957. It is a significant mark of mankind entering into the age of space flight.
In the 1970s, Pioneer-10 and Pioneer-11, as well as Voyager-1 and Voyager-2, were
successively launched by the United States. They are the first artificial spacecrafts to
reach the edge of the solar system and have currently entered into interstellar space.
From myth to fantasy, and from theory to practice, human beings have embarked on
a long journey of space flight.
3.1 Concepts of Space Flights
In general, the flight activities of the spacecrafts into or through outer space are
defined as the space flights, and similar concepts also include interstellar travel and
aerospace. The interstellar travel is the term used for crewed or un-crewed travels
between stars or planetary systems, namely including interplanetary spaceflight and
interstellar spaceflight. In practice, the former is usually confined to travels between
the planets inside the solar system, and the latter is done to travels between the stars
outside the solar system. The interstellar spaceflight will be much more difficult
than the interplanetary spaceflight. The distances between the planets in the solar
system are less than 30 Astronomical Units (AU), whereas the distances between
stars are at least hundreds of thousands of AU, and usually expressed at light-years.
Because of the vastness of those distances, interstellar spaceflight would require
a high percentage of the velocity of light, and extremely-long travel time, lasting
from decades to millennia or longer, or a combination of both. The aerospace is
also defined as the human efforts in science, engineering and business to fly in the
Earth’s atmosphere (aeronautics) and surrounding space (astronautics). Sometimes,
aerospace especially refers to the general term for the activities of entering, exploring,
developing and utilizing outer space and celestial bodies beyond the Earth.
Currently, astronautic activities are usually divided into three types: space technology, space science and space application. The space technology is a comprehensive engineering technology that provides technical means and guarantees conditions
for various space activities; the space science encompasses all of the scientific disciplines to explore and study various phenomena and laws occurring in outer space by
using the space technology; the space application refers to the utilization of the space
technology and its development of space resources, in the national economy, national
defense construction, scientific research, cultural education, as well as other fields.
the space resources refer to various environments, energy and materials that can be
exploited and utilized by human beings in outer space, including high-altitude space,
high vacuum, ultra-low temperature, strong radiation and microgravity environment,
solar energy sources, as well as rare material resources obtained from extraterrestrial
celestial bodies. There is a mutual needing and supporting relationship among the
space technology, space science and space application, and they are inseparable from
each other to form together with a whole of space activities.
3 A Brief History of Space Flight
October 1957. It is a significant mark of mankind entering into the age of space flight.
In the 1970s, Pioneer-10 and Pioneer-11, as well as Voyager-1 and Voyager-2, were
successively launched by the United States. They are the first artificial spacecrafts to
reach the edge of the solar system and have currently entered into interstellar space.
From myth to fantasy, and from theory to practice, human beings have embarked on
a long journey of space flight.
3.1 Concepts of Space Flights
In general, the flight activities of the spacecrafts into or through outer space are
defined as the space flights, and similar concepts also include interstellar travel and
aerospace. The interstellar travel is the term used for crewed or un-crewed travels
between stars or planetary systems, namely including interplanetary spaceflight and
interstellar spaceflight. In practice, the former is usually confined to travels between
the planets inside the solar system, and the latter is done to travels between the stars
outside the solar system. The interstellar spaceflight will be much more difficult
than the interplanetary spaceflight. The distances between the planets in the solar
system are less than 30 Astronomical Units (AU), whereas the distances between
stars are at least hundreds of thousands of AU, and usually expressed at light-years.
Because of the vastness of those distances, interstellar spaceflight would require
a high percentage of the velocity of light, and extremely-long travel time, lasting
from decades to millennia or longer, or a combination of both. The aerospace is
also defined as the human efforts in science, engineering and business to fly in the
Earth’s atmosphere (aeronautics) and surrounding space (astronautics). Sometimes,
aerospace especially refers to the general term for the activities of entering, exploring,
developing and utilizing outer space and celestial bodies beyond the Earth.
Currently, astronautic activities are usually divided into three types: space technology, space science and space application. The space technology is a comprehensive engineering technology that provides technical means and guarantees conditions
for various space activities; the space science encompasses all of the scientific disciplines to explore and study various phenomena and laws occurring in outer space by
using the space technology; the space application refers to the utilization of the space
technology and its development of space resources, in the national economy, national
defense construction, scientific research, cultural education, as well as other fields.
the space resources refer to various environments, energy and materials that can be
exploited and utilized by human beings in outer space, including high-altitude space,
high vacuum, ultra-low temperature, strong radiation and microgravity environment,
solar energy sources, as well as rare material resources obtained from extraterrestrial
celestial bodies. There is a mutual needing and supporting relationship among the
space technology, space science and space application, and they are inseparable from
each other to form together with a whole of space activities.