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

Escape Velocities of the Planets
Planet Escape Velocity (km/s)
Mercury 3.20
Venus 10.08
Earth 11.12
Mars 4.96
Jupiter 59.20
Saturn 35.20
Uranus 20.80
Neptune 24.00
Pluto 1.1
accelerated from rest, starting an infinite distance away.
The escape velocity of Earth is about 11 km/s. If the
body’s velocity is less than the escape velocity, it is said to
be gravitationally bound. (See table, “Escape Velocities of
the Planets.”)
escape-velocity orbit
The orbit achieved around the Sun by a spacecraft escaping
from Earth’s gravity.
Esnault-Pelterie, Robert A. C. (1881–1957)
A French engineer and aviation pioneer who invented the
joystick and built the first monoplane and radial engine.
He also tested many liquid-propellant rocket engines,
including some that used cryogenic fuels, and put forward
ideas for long-range ballistic missiles that won him
support from the French Army for his rocket experiments.
In 1930 he published his fundamental work, L’Astronautique,
89 and in 1935 a sequel, L’Astronautique-Complément. 90
A crater on the Moon’s farside is named after him.
ESOC (European Space Operations Centre)
ESA’s center for operating spacecraft, located in Darmstadt,
Germany.
Esrange
An international sounding rocket and balloon launch
facility located near Kiruna in northern Sweden and
operated by the Swedish Space Corporation. 277
ESRIN (European Space Research Institute)
An ESA (European Space Agency) center in Frascati,
Italy, responsible for analyzing and distributing remote
sensing data from ESA (ERS and Envisat) and non-ESA
(Landsat, NOAA-TIROS, MOS, JERS, SPOT) Earth
observation missions.
Etalon 127
ESRO (European Space Research Organisation)
An organization formed in 1962 by 10 European nations
plus Australia, which made available its rocket-firing
range at Woomera. Between 1968 and 1972, ESRO
launched seven satellites—Iris (ESRO-2B), Aurora
(ESRO-1A), HEOS-1, Boreas, HEOS-2, TD-1A, and
ESRO-4—using NASA rockets. In 1975, ESRO and its sister
organization ELDO (European Launcher Development
Organisation) merged to form ESA (European
Space Agency). 175
ESSA (Environmental Science
Services Administration)
An American government agency that was a precursor of
NOAA(National Oceanic and Atmospheric Administration).
ESSA managed the first experimental TIROS
satellites and TOS (TIROS Operational System). TOS
satellites were designated ESSA 1, ESSA 2, etc., once
they had been successfully launched.
ESSP (Earth System Science Pathfinder)
Small, rapidly developed missions that form part of
NASA’s Earth Probes program. They include VCL (Vegetation
Canopy Lidar), GRACE (Gravity Recovery and
Climate Experiment), CALIPSO, and CloudSat.
ESTEC (European Space Research
and Technology Centre)
An ESA (European Space Agency) establishment, at
Noordwijk in the Netherlands, responsible for the study,
development, and testing of ESA spacecraft. ESTEC is
also the home of technological development programs
that lay the groundwork for future missions.
Etalon
Soviet passive geodetic satellites; “etalon” is Russian for
“standard.” Each is spherical and covered with 306
antenna arrays, and each array contains 14 corer cubes for
laser reflection. Etalons were designed and launched to
enable the complete characterization of Earth’s gravitational
field at the altitude and inclination planned for the
GLONASS navigation satellites. They were also used to
refine understanding of the Earth-Moon gravitational system,
to determine the effect of nongravitational forces on
satellites, and for geophysical research. Only two Etalon
satellites have been orbited, each accompanied by a pair
of GLONASS satellites. (See table, “Etalon Satellites.”)
Launch
Vehicle: Proton
Site: Baikonur
Size: 1.3 × 1.3 m
Mass: 1,415 kg