Tag Archives: Jet Propulsion Laboratory

31 January 1958, 03:48:00 UTC

Explorer 1 launch, Launch Complex 26A, Cape Canaveral Air Force Station. (NASA)

31 January 1958, 10:48 p.m., Eastern Standard Time (1 February 1958, 03:48:00 UTC): The United States of America launched its first successful satellite, Explorer 1, from Launch Complex 26A at the Cape Canaveral Air Force Station, Cape Canaveral, Florida. The satellite entered an orbit with a perigee of 224 miles (360 kilometers) and apogee of 1,575 miles (2,535 kilometers). It completed one orbit every 1 hour, 54.9 minutes.

Explorer 1 was designed and built by the Jet Propulsion Laboratory (JPL) at the California Institute of Technology, Pasadena, California. The satellite carried a cosmic ray detector, internal and external temperature sensors, and a micrometeorite detector. Powered by batteries, it transmitted data for 105 days.

Cutaway illustration of Explorer 1 satellite and booster. (NASA)

The satellite was launched aboard a Juno-1 four-stage liquid-fueled rocket, produced by the U.S. Army Ballistic Missile Agency (ABMA). The Juno satellite launch vehicle was developed from the Jupiter-C intermediate range ballistic missile, and externally appears virtually identical. The complete Explorer 1/Juno-1 was 71.25 feet (21.72 meters) tall and weighed 64,080 pounds (29,066 kilograms) at launch.

The Juno-1 first stage was 69 feet, 8 inches (21.234 meters) long and 5 feet, 10 inches (1.778 meters) in diameter. Four stabilizing fins had a maximum span of 12 feet, 8 inches (3.861 meters). The engine was a Rocketdyne A-7, which burned a combination of Hydyne and liquid oxygen. The A-7 was rated at 83,000 pounds of thrust (369.20 kilonewtons) and burned for 2 minutes, 35 seconds.

The second stage consisted of a cluster of 11 JPL “Baby Sergeant” solid-rocket boosters, producing a total of 16,500 pounds of thrust (73.40 kilonewtons) and burned for 6.5 seconds. These were scaled-down version of the Thiokol XM100 Sergeant booster. They were 3 feet, 10 inches (1.168 meters) long and 6.00 inches (15.24 centimeters) in diameter. Each booster contained 50 pounds ( kilograms) of solid fuel. The second stage weighed 1,020 pounds (463 kilograms).

Juno-1 satellite launch vehicle number RS-29, marked UE, ready for launch, 31 January 1958. (NASA)

The third stage was powered by three Baby Sergeant boosters, producing 4,500 pounds of thrust (20.02 kilonewtons). These were clustered inside the second stage boosters, and both the second and third stage were covered by a fiberglass “tub” which could be spun up to 750 r.p.m. to stabilize the rocket after launch. The third stage weighed 280 pounds (127 kilograms).

The fourth stage consisted of the Explorer satellite and a single Baby Sergeant booster. The booster remained attached to the satellite in orbit. The Explorer 1 satellite was 2 feet, 6.75 inches (0.781 meters) long, and 6.50 inches (16.51 centimeters) in diameter. It weighed 30.66 pounds (13.91 kilograms). Including its booster, the fourth stage was 6 feet, 8.75 inches (2.051 meters) long and weighed 80 pounds (36 kilograms). The fourth stage booster produced 1,500 pounds of thrust (6.67 kilonewtons) for 6.5 seconds. This gave the Explorer 1 an orbital velocity of approximately 18,000 miles per hour (28,968 kilometers per hour).

Explorer 1 remained in orbit for 12 years, 2 months and 1 day. On 31 March 1970, its orbit decayed and the satellite re-entered Earth’s atmosphere over the Pacific Ocean and was destroyed.

Explorer 1 artificial satellite. (NASA)

© 2019, Bryan R. Swopes

28 November 1964, 14:22:01.309 UTC

Mariner 4 lifts off from LC-12, Cape Kennedy Air Force Station, 9:22 a.m. EST, 28 November 1964. (NASA)

28 November 1964, 14:22:01.309 UTC: Mariner 4, a space probe designed and built by the Jet Propulsion Laboratory (JPL), lifted off from Launch Complex 12 at the Cape Kennedy Air Force Station, Cape Kennedy, Florida. The two-stage launch vehicle consisted of an Atlas D, number 288, and an Agena D, number 6932.

The Mariner 4/Agena D separated from the first stage Atlas booster at 14:27:23 UTC. A 2 minute, 24 second burn placed the Mariner/Agena in an Earth orbit. At 15:02:53, a one minute, 35 second burn placed the vehicle into a Mars Transfer Orbit. Mariner 4 separated from the Agena D at 15:07:09 UTC. Mariner then went into cruise mode.

Mariner 4 (NASA)
Mariner 4 during Weight Test (NASA/JPL 293_7150Bc)

The mission of Mariner 4 was to “fly by” Mars to take photographic images and gather scientific data, then relay this to tracking stations on Earth. The spacecraft carried an imaging system, cosmic dust detector, cosmic-ray telescope, magnetometer, radiation detector, solar plasma probe and an occultation experiment.

Mariner 4 overall height, including the mast, was 289 centimeters. The body of the spacecraft had a width of 127 centimeters (4 feet, 2 inches) across the diagonal, and was 45.7 centimeters (1 foot, 6 inches high. 260.8 kilograms (118.3 pounds). Power was supplied by four solar panels, each 176 centimeters (5 feet, 9.3 inches) long and 90 centimeters (2 feet, 11.4 inches) wide. The panels had 28,224 individual solar cells capable of producing 310 watts at Mars.

The rocket, a “1-½ stage” liquid-fueled Atlas LV-3, number 228, was built by the Convair Division of General Dynamics at San Diego, California. It was developed from a U.S. Air Force SM-65 Atlas D intercontinental ballistic missile, modified for use as an orbital launch vehicle.

The LV-3 was 65 feet (19.812 meters) long from the base to the adapter section, and the tank section is 10 feet (3.038 meters) in diameter. The complete Atlas-Agena D orbital launch vehicle is 93 feet (28.436 meters) tall. When ready for launch it weighed approximately 260,000 pounds (117,934 kilograms).

The Atlas’ three engines were built by the Rocketdyne Division of North American Aviation, Inc., at Canoga Park, California. Two Rocketdyne LR89-NA-5 engines and one LR105-NA-5 produced 341,140 pounds (1,517.466 kilonewtons) of thrust. The rocket was fueled by a highly-refined kerosene, RP-1, with liquid oxygen as the oxidizer.

The second stage was an Agena D, built by Lockheed Missiles and Space Systems, Sunnyvale, California. The Agena D was 20 feet, 6 inches (6.299 meters) long and had a maximum diameter of 5 feet, 0 inches (1.524 meters). The single engine was a Bell Aerosystems Company LR81-BA-11, with 16,000 pounds of thrust (71.1 kilonewtons). It was also liquid fueled, but used a hypergolic mixture of nitric acid and UDMH. This engine was capable of being restarted in orbit.

Mariner 4 made its closest approach to Mars, 9,846 kilometers (6,118 miles) on 15 July 1965. The final contact with the probe occurred on 21 December 1967.

The first photographic image of Mars was captured by Mariner 4’s imaging system on 15 July 1965 and was transmitted to Earth the following day. (NASA/JPL-Caltech)
Digital image of the surface of Mars, 14 July 1965. (NASA)

© 2019, Bryan R. Swopes

27 August 1962, 06:53:14 UTC, T minus Zero

Engine ignition of Mariner 2 Atlas Agena B at LC-12, Cape Canaveral AFS, 2:53 a.m., EST, 27 August 1962. (NASA)

27 August 1962: At 06:53:14 UTC (2:53 a.m., Eastern Daylight Time), Mariner 2 lifted off from Launch Complex 12 at Cape Canaveral Air Force Station, Florida, aboard an Atlas-Agena B launch vehicle. This was the second space probe to be sent to Venus.

Mariner 1 and 2 were identical space probes built by the Jet Propulsion Laboratory (JPL) of the California Institute of Technology (Caltech), Pasadena, California. The spacecraft were designed to obtain radiometric temperatures of Venus, and to measure the Interplanetary Magnetic Field.

The Mariner 1 mission failed when the launch vehicle veered off course and was destroyed by the Range Safety Officer, 4 minutes, 53 seconds into its flight, 22 July 1962.

Mariner 2 under final inspection. (NASA)

The Atlas Agena B combined an Atlas LV-3A rocket with an Agena B upper stage. The Atlas was derived from the U.S. Air Force SM-65 Atlas intercontinental ballistic missile (ICBM), and was built by the Convair Division of General Dynamics at San Diego, California.

The height of the total vehicle, including the protective shroud encasing Mariner, 103 feet, 5 inches (31.70 meters). The Atlas Agena B first stage was 20.70 meters (67 feet, 11 inches) long, with a maximum diameter of 3.05 meters (10 feet). The maximum width across the booster section was 4.88 meters (16 feet).

The LV-3A is a “1-½ stage” liquid-fueled rocket with three engines. The “half-stage,” was a booster section consisting of two LR89-NA-5 rocket engines. This stage produced approximately 369,800 pounds of thrust (1,645 kilonewtons). The center, or “sustainer,” engine is a LR105-NA-5, rated at 86,800 pounds of thrust (386 kilonewtons). Both engines were built by the Rocketdyne Division of North American Aviation, Inc., at Canoga Park, California. The Atlas rocket used liquid oxygen and RP-1 (a highly-refined kerosene) propellant. The LV-3A had a total thrust of 456,587 pounds (2,031 kilonewtons).

The second stage was an Agena B, built by Lockheed Missiles and Space Systems, Sunnyvale, California. This engine was capable of being restarted in orbit. The Agena B was 7.20 meters (23 feet, 7 inches) long and had a maximum diameter of 1.50 meters (4 feet, 11 inches). It was also liquid fueled, but used a hypergolic mixture of nitric acid and UDMH. The single engine was a Bell Aerosystems Company LR81-BA-7, with 16,000 pounds of thrust (71.1 kilonewtons).

The Mariner probe was mounted atop the Agena second stage, enclosed in a protective shroud. Mariner had a gross weight of 447 pounds (202.8 kilograms). The probe was 9 feet, 11 inches long (3.02 meters) long, folded for launch, and 5 feet (1.52 meters) wide. When antennas and the solar panels were fully expanded, the spacecraft was 11 feet, 11 inches (3.63 meters) long and had a span of 16 feet, 6 inches (5.03 meters).

Artist's conception of Mariner 2 in interplanetary space. (NASA)
Artist’s conception of Mariner 2 in interplanetary space. (NASA)

At liftoff, all three main engines were burning. After 2minutes, the two-engine booster assembly was jettisoned and the vehicle continued with the center LR105 sustainer. After 4 minutes, 25 seconds, this engine shut down and the Agena second stage separated. At this point, guidance was lost and the vehicle began to roll, but did not deviate significantly from the planned trajectory. About a minute later, guidance was restored and the mission continued.

The Agena B second stage placed the Mariner in a parking orbit at about 118 kilometers (73.3 miles) altitude. 16 minutes, 20 seconds later, the Agena engine was reignited and  Mariner 2 was then placed on a trajectory planned to take it to Venus.

After 3 months, 17 days, at 19:59:28 UTC, 14 December 1962, the probe passed within 34,773 kilometers (21,607 miles) of Venus and measured the planet’s surface and cloud temperatures. It continued inward across the solar system and came within 105,464,560 kilometers (65,432,640 miles) of the sun.

The last transmission was received at 07:00 UTC, 3 January 1963, 129 days into the mission. Mariner 2 remains in orbit around the sun, circling every 292 days.

Mariner 2, carried alloft by Atlas LV3 179D, accelerates past the gantry, 06:53 UTC, 26 August 1962 (NASA)
The Atlas Agena B, carrying Mariner 2, accelerates toward orbit, 06:53 UTC, 27 August 1962 (NASA)

© 2018, Bryan R. Swopes

12 August 1960, 09:39:43 UTC

The Thor Delta launch vehicle at Launch Complex 17A, Cape Canaveral Air Force Station. The spherical capsule containing the Echo 1A is visible at the top of the Altair solid fuel third stage. (NASA)

12 August 1960: At 5:39:43 a.m., Eastern Daylight Savings Time, the Echo 1A experimental passive communications satellite was launched from LC-17A at Cape Canaveral Air Force Station, Florida. The launch vehicle was a Thor-Delta three stage rocket. It entered a nearly circular 944 mile × 1,048 mile orbit (1,519 × 1,687 kilometers). The orbital period was 118.3 minutes.

The satellite was a 100 foot diameter (30.48 meter) Mylar polyester balloon with a reflective surface. The material was just 0.0127 millimeters thick. The mass of the satellite was 66 kilograms (145.5 pounds). In orbit, the balloon envelope was kept inflated by gas from evaporating liquid. It had been constructed by the G.T. Schjeldahl Company, Northfield, Minnesota. This was the second Echo satellite. The first had failed to reach orbit when launched 13 March 1960.

Later the same day, a microwave transmission from the Jet Propulsion Laboratory, Pasadena, California, was reflected off the Echo 1A satellite and received at the Bell Laboratories, Homdel, New York.

According to NASA, “The success of Echo 1A proved that microwave transmission to and from satellites in space was understood and demonstrated the promise of communications satellites. The vehicle also provided data for the calculation of atmospheric density and solar pressure due to its large area-to-mass ratio. Echo 1A was visible to the unaided eye over most of the Earth (brighter than most stars) and was probably seen by more people than any other man-made object in space.”

Echo 1A remained in Earth orbit until 24 May 1968.

An Echo satellite undergoing static inflation tests inside a blimp hangar at Weeksville NAS, North Carolina. The vehicle, which shows scale, is a 1959 Plymouth Suburban 4-door station wagon. (NASA)

The Delta was a three-stage expendable launch vehicle which was developed from the Douglas Aircraft Company’s SM-75 Thor intermediate-range ballistic missile.

Designated Thor DM-19, the first stage was 60.43 feet (18.42 meters) long and 8 feet (2.44 meters) in diameter. Fully fueled, the first stage had a gross weight of 108,770 pounds (49,337 kilograms). It was powered by a Rocketdyne LR-79-7 engine which burned liquid oxygen and RP-1 (a highly-refined kerosene rocket fuel) and produced 170,565 pounds of thrust (758.711 kilonewtons). This stage had a burn time of 2 minutes, 45 seconds.

The second stage was an Aerojet General Corporation-built Delta 104. It was 19 feet, 3 inches (5.88 meters) long with a maximum diameter of 4 feet, 6 inches (1.40 meters). The second stage had a gross weight of 9,859 pounds (4,472 kilograms). It used an Aerojet AJ10-104 rocket engine which burned a hypergolic  mixture of nitric acid and UDMH. The second stage produced 7,890 pounds of thrust (35.096 kilonewtons) and burned for 4 minutes, 38 seconds.

The third stage was an Alleghany Ballistics Laboratory Altair 1. It was 6 feet long, 1 foot, 6 inches in diameter and had a gross weight of 524 pounds (238 kilograms). This stage used a solid-fuel Thiokol X-248 rocket engine, producing 2,799 pounds of thrust (12.451 kilonewtons). Its burn time was 4 minutes, 16 seconds.

© 2016, Bryan R. Swopes

24 July 1950

Bumper 8 launch at Launch Complex 3, Cape Canaveral Air Force Station, Florida, 24 July 1950. The wooden structure in the foreground houses the firing crew and support personnel. (NASA)

24 July 1950: The first rocket launch at Cape Canaveral, Florida, took place. Bumper 8 was a two-stage rocket consisting of a captured German V-2 ballistic missile as the first stage and a WAC Corporal sounding rocket as the upper, second, stage. The rocket lifted off from Launch Complex 3 at the Cape Canaveral Air Force Station and followed a ballistic trajectory over the Joint Long Range Proving Ground. This was a low-angle atmospheric flight. The WAC Corporal reached an altitude of 10 miles (16.1 kilometers) and traveled 200 miles (322 kilometers) downrange.

The Bumper Project was a U.S. Army Ordnance Corps program, with overall responsibility contracted to the General Electric Corporation. The V-2s used in the Bumper Project were modified at accept the WAC Corporal second stage. Compressed air was used to separate the stages after the V-2 engine was cut off.

The V2, or Vergeltungswaffen 2 (also known as the A4, Aggregat 4) was a ballistic missile weighing 28,000 pounds (12,500 kilograms) when fully loaded. It carried a 2,200 pound (1,000 kilogram) explosive warhead of amatol, a mixture of TNT and ammonium nitrate. Propellant was a 75/25 mixture of of ethanol and water with liquid oxygen as oxidizer.

When launched, the rocket engine burned for 65 seconds, accelerating the rocket to 3,580 miles per hour (5,761 kilometers per hour) on a ballistic trajectory. The maximum range of the rocket was 200 miles (322 kilometers) with a peak altitude between 88 and 128 miles (142–206 kilometers), depending on the desired range. On impact, the rocket was falling at 1,790 miles per hour (2,881 kilometers per hour).

The V-2 could only hit a general area and was not militarily effective. Germany used it against England, France, The Netherlands and Belgium as a terror weapon. More than 3,200 V-2 rockets were launched against these countries.

At the end of World War II, many V-2 rockets and components were captured by Allied forces and were brought to the United States for research, along with many of the German engineers, scientists and technicians who had worked on the German rocket program. Others were captured by the Soviet army.

Bumper 8 supported by a gantry at Launch Complex 3, Cape Canaveral Air Force Station, Florida. (U.S. Army)

The WAC Corporal was a liquid-fueled hypergolic rocket. After separation from the first stage, the WAC Corporal was capable of reaching more than 80 miles (129 kilometers). It was designed by the Jet Propulsion Laboratory in Pasadena, California, and built by Douglas Aircraft. The rocket carried small research packages into the upper atmosphere. The two-stage rocket was used to develop launch techniques and to refine the separation of upper stages at very high speed.

Now named the Kennedy Space Center, but known simply as “The Cape,” the location was selected to allow rocket testing to take place over the Atlantic Ocean, minimizing danger to persons and property. As one of the points within the United States closest to the Equator, rockets launched on an eastward trajectory receive additional velocity due to the Earth’s rotation.

Launch Pad 3 at Cape Canaveral, circa 1950. A rocket is on the pad surrounded by the gantry structure. (U.S. Air Force)
Launch Complex 3 at Cape Canaveral, 28 July 1950. The Bumper 7 two-stage rocket is on the pad surrounded by a gantry structure. It was launched the day after this photograph was taken. (U.S. Air Force)

© 2016, Bryan R. Swopes