Ranger 1
Mission type | Technology | ||||||
---|---|---|---|---|---|---|---|
Operator | NASA | ||||||
Harvard designation | 1961 Phi 1 | ||||||
COSPAR ID | 1961-021A | ||||||
SATCAT no. | 173 | ||||||
Mission duration | 7 days | ||||||
Spacecraft properties | |||||||
Manufacturer | Jet Propulsion Laboratory | ||||||
Launch mass | 306.2 kilograms (675 lb) | ||||||
Power | 150.0 W | ||||||
Start of mission | |||||||
Launch date | August 23, 1961, 10:04:10 | UTC||||||
Rocket | LC-12 | ||||||
End of mission | |||||||
Decay date | 30 August 1961 | ||||||
Orbital parameters | |||||||
Reference system | Semi-major axis 6,690.3 kilometres (4,157.2 mi) | | |||||
Eccentricity | 0.019939 | ||||||
Perigee altitude | 179 kilometres (111 mi) | ||||||
Apogee altitude | 446 kilometres (277 mi) | ||||||
Inclination | 32.9 degrees | ||||||
Period | 91.1 minutes | ||||||
Revolution no. | 110 | ||||||
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Ranger 1 was a prototype spacecraft launched as part of the
Spacecraft design
The spacecraft was of the Ranger Block I design and consisted of a hexagonal base 1.5 meters (4 ft 11 in) across upon which was mounted a cone-shaped 4-meter (13 ft) high tower of aluminum struts and braces. Two solar panel wings measuring 5.2 meters (17 ft) from tip to tip extended from the base. A high-gain directional dish antenna was attached to the bottom of the base. Spacecraft experiments and other equipment were mounted on the base and tower. Instruments aboard the spacecraft included a Lyman-alpha telescope, a rubidium-vapor magnetometer, electrostatic analyzers, medium-energy range particle detectors, two triple coincidence telescopes, a cosmic-ray integrating ionization chamber, cosmic dust detectors, and solar X-ray scintillation counters. There was no camera or midcourse correction engine on the Block I spacecraft.[1]
The communications system included the high-gain antenna and an omnidirectional medium-gain antenna and two transmitters, one at 960.1
Mission
The Ranger 1 spacecraft was designed to go into an Earth parking orbit and then move into a 60,000-by-1,100,000-kilometre (37,000 by 684,000 mi) Earth orbit. The purpose of the mission was mainly as an engineering test to verify the functionality of the Ranger hardware.[1]
Launch delays
- Delay of the 1st countdown
- July 26: Trajectory information required by the Range Safety Officer was delayed.
- July 27: A guidance system malfunction in the Atlas booster.
- July 28: Engineers found that the guidance program to be fed into the Cape computer contained an error.
- 1st countdown. July 29.
- 83 minutes before launch: Power interruptions occurred, requiring momentary holds to permit all stations to check and recover.
- 28 minutes before launch: Commercial electrical power failed. Inadequate allowance had been made for changes in cable sag caused by variations in temperature on the new power poles recently installed at Cape Canaveral Air Force Station.
- 2nd countdown. July 30. Engineers discovered a leak in Ranger's attitude control gas system.
- 3rd countdown. July 31. A valve malfunctioned in the liquid-oxygen tank on the Atlas booster.
- 4th countdown. August 1. Ground controllers turned on a spacecraft command applying high voltage to the scientific experiments for calibration purposes. Immediately all stations reported a major spacecraft failure. An electrical malfunction had triggered multiple commands from the central clock timer, and Ranger 1 "turned on" as it had been programmed to do in orbit. The explosive squibs fired, solar panels extended inside the shroud, and all the experiments commenced to operate. Project engineers disengaged Ranger 1 from the Agena and hastily returned it to Hangar AE. Meantime, the launch was rescheduled for August 22, the next available opportunity. Subsequent tests and investigations determined the activating mechanism to have been a voltage discharge to the spacecraft frame; although engineers suspected one or two of the scientific instruments, they could not determine the precise source of the discharge with certainty. In the days that followed, they replaced and requalified the damaged parts and modified the circuitry to prevent a recurrence of this kind of failure.[2]
Launch
During the first half of 1961, Lockheed introduced the new Agena B stage which replaced the early test-model Agena A of 1959-60. Agena B was more powerful and had in-orbit restart capability. Its first flight with the launch of
Footnotes
See also
References
- "National Space Science Data Center - Ranger 1". National Air and Space Administration. Retrieved 19 June 2012.
- "LUNAR IMPACT: A History of Project Ranger - Part I. THE ORIGINS OF RANGER - TEST FLIGHTS AND DISAPPOINTMENTS - A LEARNING EXPERIENCE". NASA. 2006. Retrieved 2010-08-30.
External links
- Standard Trajectory Ranger/Agena 1 <broken link>
- Space flight operations memorandum - Ranger 1 (Post-Flight Mission Analysis) <broken link>
- Field operations memorandum - Ranger A-1, part 1 <broken link>
- Lunar impact: A history of Project Ranger (PDF) 1977 <broken link>