Atlas-Agena launch vehicles-used by NASA during the 1960s to launch a variety of payloads to Earth orbit, the moon, and the near planets-sent Mariner spacecraft (200-260 kilograms) on their way to Venus or Mars. The Agena upper stage, developed by Lockheed Missiles and Space Co. for the Air Force, was capable of restarting its engines, thus permitting the spacecraft to be positioned more precisely. Paired with the Atlas booster, Agena B was used in 1962 for the first two Mariner flights (the Atlas stage malfunctioned during the Mariner 1 launch). Atlas-Agena D, with an improved upper stage that could accept a greater variety of payloads, launched the next three Mariners in 1964 and 1967.
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Characteristics |
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Height (m) |
21.9 |
7.2 |
30.6 |
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Diameter (m) |
3 |
1.5 |
- |
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Launch weight (kg) |
117 780 |
7022 |
124 802 |
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Propulsion system: | |||
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Powerplant |
MA-3 propulsion system
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- |
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Thrust (Kilonewtons) |
1600 |
71.2 |
1670 |
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Propellant a |
LOX/RP-1 |
IRFNA/UDMH |
- |
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Payload capacity (kg) |
- |
- |
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Origin |
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Contractor |
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- |
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Program Use |
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Remarks |
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Characteristics |
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Total With Adapter |
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Height (m) |
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Diameter (m) |
3 |
1.5 |
- |
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Launch weight (kg) |
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Propulsion system: | |||
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Powerplant |
MA-5 propulsion system
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- |
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Thrust (Kilonewtons) |
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Propellant a |
LOX/RP-1 |
N2O4/UDMH |
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Payload capacity (kg) |
- |
- |
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Origin |
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Contractors |
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- |
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Program Use |
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Remarks |
The Agena D stage could accept a greater variety of payloads than could the Agena B model. | ||
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Height (m) |
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Diameter (m) |
3.05 |
3.05 |
- |
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Launch weight (kg) |
128 879 |
17 145 |
146 024 |
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Propulsion system: | |||
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Powerplant |
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- |
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Thrust (Kilonewtons) |
1700/1900 |
133.4 |
1890/2050 |
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Propellant a |
LOX/RP-1 |
LOX/LH2 |
- |
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Payload capacity (kg) |
- |
- |
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Origin |
Air Force ICBM |
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Contractors |
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- General Dynamics/Convair
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Program Use |
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Remarks |
Centaur, the first U.S. launch vehicle to use liquid hydrogen as a propellant, was originally scheduled for operations in the early 1960s for Mars and Venus probes. Because of delays in the vehicle's development, however, it was not ready until 1966. One of the serious problems with the stage's development was hydrogen loss; heat transfer between the oxygen and hydrogen fuel tanks caused the liquid hydrogen to evaporate. | ||
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Height (m)
25.9
22.2
7.1
9.7
(17.7)
48.8
Diameter (m)
3.05
3.05
3.05
3.05
4.3
-
Launch weight (kg)
226 800
123 830
33 112
17 700
3092
631 334
Propulsion system:
Powerplant
United Technology 1205
Aerojet YLR87-AJ-11
Aerojet YLR91-AJ-11
Pratt & Whitney (2)
RL-10A-3-3
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-
Thrust (Kilonewtons)
10 680 (combined)
2310
449.2
133.4
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13 550
Burn time (sec)
110
150
208
450
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918
Payload capacity (kg)
-
-
-
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-
Origin
Air Force Titan IIID modified to NASA
requirements
NASA design
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Contractors
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Program Manager
R. A. Mattson, NASA Hq.
Project Manager
Andrew J. Stofan, Lewis Research
Center
Program Use
Remarks
In this configuration, the Centaur
upper stage replaced the standard Titan third stage, called
the transtage; Centaur was capable of restarting its two
engines, a desirable characteristic for planetary missions.
During Centaur's coast phase, 14 small hydrogen peroxide
thrusters controlled attitude. When the two five-segment
solid-fueled rocket motors, together known as "stage 0",
were jettisoned, the Titan first stage ignited. These
strap-on motors provided more than four times the thrust of
the Atlas booster at liftoff.