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

Experimental, or DC-X, made several successful flights at
the White Sands Missile Range in the mid-1990s.
delta V
The change in velocity needed by a spacecraft to switch
from one trajectory to another.
deluge collection pond
A pond at a launch site that collects water used to cool
the flame deflector.
Demosat (Demonstration Satellite)
The first satellite to be placed in orbit from Sea Launch
Odyssey. It successfully tested the facility’s effectiveness.
Launch
Date: March 28, 1999
Vehicle: Zenit
Site: Sea Launch Odyssey
Orbit: 638 × 36,064 km × 1.2°
Mass (at launch): 4,500 kg
de-orbit burn 101
Denpa
An early Japanese satellite launched by ISAS(Institute of
Space and Astronautical Science) to carry out measurements
of the ionosphere; also known as REXS.
Launch
Date: August 19, 1972
Vehicle: M-3S
Site: Kagoshima
Orbit: 238 × 6,322 km × 31.0°
Mass: 75 kg
Deep Space Network The
Deep Space Operations Center,
known as the Dark Room, at
JPL, which is the nerve center of
the Deep Space Network.
NASA/JPL
density
The ratio of the mass of a substance or an object to its
volume.
de-orbit burn
The firing of a spacecraft’s engine against the direction of
motion to cut the spacecraft’s orbital speed. The speed
reduction places the spacecraft in a lower orbit. If this
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