The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

198 Intercosmos
Intercosmos
International cooperative satellites, launched by Soviet
boosters, with a variety of missions.
interference
Unwanted electrical signals or noise causing degradation
of reception on a communications circuit.
intergalactic travel
This poses all the difficulties of interstellar travel multiplied
a millionfold—the factor by which the typical distances
between neighboring galaxies exceed those
between stars in the neighborhood of the Sun. If intergalactic
travel is ever to be achieved, it will require the
development of relativistic starships that can accelerate
to well over 99% of the speed of light or, alternatively,
some method of bypassing normal space-time altogether.
International Astronautical Federation (IAF)
A nongovernmental association, with members drawn
from government organizations, industry, professional
associations, and learned societies from around the
world, that encourages the advancement of knowledge
about space and the development and application of
space assets for the benefit of humanity. It plays an
important role in disseminating information and in providing
a worldwide network of experts in space development
and utilization of space. Founded in 1951, the IAF
today has 152 institutional members from 45 countries.
Together with its associates, the International Academy
of Astronautics and the International Institute of Space
Law, the IAF organizes an International Astronautical
Congress, which is held each year in a different country,
and other seminars and events.
International Geophysical Year (IGY)
A comprehensive series of global geophysical activities
spanning the period from July 1957 to December 1958
and timed to coincide with the high point of the 11-year
cycle of sunspot activity. It was proposed by the International
Council of Scientific Unions (ICSU) in 1952 following
a suggestion by Lloyd Berkner. In March 1953,
the National Academy of Science appointed a U.S.
National Committee to oversee American participation
Interbol Missions
Spacecraft Launch Date Orbit Mass (kg)
Interbol 1 Aug. 2, 1995 4,426 × 188,331 km × 68.2° 1,250
Interbol 2 Aug. 29, 1996 239 × 1,093 km × 62.8° 1,400
in the IGY. The American program included investigations
of aurora and airglow, cosmic rays, geomagnetism,
glaciology, gravity, the ionosphere, determinations of
longitude and latitude, meteorology, oceanography, seismology,
solar activity, and the upper atmosphere. In connection
with upper-atmosphere research, the United
States undertook to develop an orbiting satellite program.
It was from the IGY rocket and satellite research
that the United States developed its space program. 164
International Launch Services (ILS)
An organization formed in June 1995 with the merger of
Lockheed Martin Commercial Launch Services, the marketing
and mission management arm for the Atlas vehicle,
and Lockheed-Khrunichev-Energia International, the
marketing and mission management arm for commercial
Proton launches.
International Quiet Sun Years (IQSY)
The period from January 1, 1964, to December 31, 1965,
near solar minimum, when solar and geophysical phenomena
were studied by observatories around the world
and by spacecraft to improve our understanding of solarterrestrial
relations.
International Solar Polar Mission
See Ulysses.
International Space Science Institute
A forum in which space scientists, astronomers, groundbased
observers, and theorists can work together on the
joint analysis and interpretation of their data to achieve a
deeper understanding of space mission results. ISSI funding
comes from ESA (European Space Agency), the Swiss
federal government, the canton of Bern, and the Swiss
National Science Foundation.
International Space Station (ISS)
See article, pages 199–204.
interplanetary magnetic field
The weak magnetic field filling interplanetary space, with
field lines usually connected to the Sun. The IMF is kept
out of Earth’s magnetosphere, but the interaction of the
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