The Pegasus Project was a NASA initiative to study the frequency of

micrometeoroid A micrometeoroid is a tiny meteoroid: a small particle of rock in space, usually weighing less than a gram. A micrometeorite is such a particle that survives passage through Earth's atmosphere and reaches Earth's surface. The term "micrometeor ...

impacts on spacecraft by means of a

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the earliest constellation ...

of three

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioiso ...

s launched in 1965. All three Pegasus satellites were launched by

Saturn I The Saturn I was a rocket designed as the United States' first medium lift launch vehicle for up to low Earth orbit payloads.Terminology has changed since the 1960s; back then, 20,000 pounds was considered "heavy lift". The rocket's first st ...

rocket A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entir ...

s, and remained connected with their upper stages. The Pegasus satellites were named for the winged horse of Greek mythology and was first lofted into space by a NASA

rocket on February 16, 1965. Like its namesake, the Pegasus satellite was notable for its "wings", a pair of -long, -wide arrays of 104 panels fitted with sensors to detect punctures by micrometeoroids at high altitudes, in support of the Apollo Program to send manned lunar landing missions starting by 1970. Micrometeoroids were believed to be potentially hazardous to the Apollo crew if they could puncture the spacecraft skin. The sensors successfully measured the frequency, size, direction and penetration of scores of micrometeoroid impacts. The satellite also carried sample protective shields mounted on the arrays. The

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...

Marshall Space Flight Center The George C. Marshall Space Flight Center (MSFC), located in Redstone Arsenal, Alabama (Huntsville postal address), is the U.S. government's civilian rocketry and spacecraft propulsion research center. As the largest NASA center, MSFC's firs ...

was responsible for the design, production and operation of the three Pegasus satellites which were launched by Saturn I rocket test flights in 1965. At launch, a boilerplate

Apollo Command/Service Module The Apollo command and service module (CSM) was one of two principal components of the United States Apollo spacecraft, used for the Apollo program, which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as a mother sh ...

and

launch escape system A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, s ...

tower were atop the Saturn I, with the Pegasus experiment folded inside the Service Module. After first stage separation and second-stage ignition, the launch escape system was jettisoned. When the second stage attained orbit, the 10,000-pound Apollo boilerplate Command and Service modules were jettisoned into a separate orbit. Then a motor driven device extended the winglike panels on the Pegasus to a span of . The Pegasus wings remained attached to the Saturn I's second stage as planned. A television camera, mounted on the interior of the Service Module adapter, provided pictures of the satellite deploying in space and as historian Roger E. Bilstein has written, "captured a vision of the eerie silent wings of Pegasus I as they haltingly deployed." The satellite exposed more than of instrumented surface, with thickness varying up to . Ernst Stuhlinger, then director of the MSFC Research Projects Laboratory, noted that all three Pegasus missions provided more than data on micrometeoroid penetration. Scientists also were able to gather data regarding gyroscopic motion and orbital characteristics of rigid bodies in space, lifetimes of electronic components in the space environment, and thermal control systems and the degrading effects of space on thermal control coatings. Space historian Roger Bilstein reported that for physicists the Pegasus missions provided additional knowledge about the radiation environments of space, the Van Allen radiation belts and other phenomena.

Orbits

Pegasus 1 Pegasus 1 or I, known before launch as Pegasus A, was an American satellite which was launched in 1965 to study micrometeoroid impacts in low Earth orbit. It was the first of three Pegasus satellites to be launched. The Pegasus spacecraft were ma ...

**Launched: February 16, 1965 **Launch vehicle:

A-103 A103, A.103, A 103 or A-103 may refer to: * A103 road (England), a road in London connecting Lower Holloway to Hornsey * A 103 motorway (Germany) , a German autobahn * AS-103, a 1965 spaceflight in the Apollo program * Agusta A.103 The Agusta A ...

**Orbital inclination: 31.7 degrees. **

Perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any el ...

: 510 km **Apogee: 726 km **Launch weight: 10.5 tons. **Dry weight: 1451.5 kg **Decayed: September 17, 1978 ** International Designator
1965-009A
*

Pegasus 2 Pegasus 2 or Pegasus II, known before launch as Pegasus B was an American satellite which was launched in 1965 to study micrometeoroid impacts in Low Earth orbit. It was the second of three Pegasus satellites to be launched, following the launch ...

**Launched: May 25, 1965 **Launch vehicle:

A-104 A104, A.104 or A-104 may refer to: * AS-104, a 1965 spaceflight in the Apollo program * Aero A.104, a 1937 Czechoslovakian biplane light bomber and reconnaissance aircraft * Agusta A.104, a 1960 Italian prototype light helicopter * RFA Eaglesdale ...

**Orbital inclination: 31.7 degrees. **

: 502 km **Apogee: 740 km **Launch weight: 10.46 tons. **Dry weight: 1451.5 kg **Decayed: November 3, 1979 **International Designator
1965-039A
*

Pegasus 3 Pegasus 3 or III, also known as Pegasus C before launch, was an American satellite which was launched in 1965 to study micrometeoroid impacts in Low Earth orbit. It was the last of three Pegasus satellites to be launched, the previous two having ...

**Launched: July 30, 1965 **Launch vehicle:

A-105 A105 may refer to: Roads * A105 road (England), a road in London connecting Canonbury and Enfield * A105 motorway (France), a road near Combs-la-Ville * A105 is the route number of the Rublevo-Uspenskoe Shosse west of Moscow Other uses * AS-105 ...

**Orbital inclination: 28.9 degrees. **

: 441 km **Apogee: 449 km **Launch weight: 10.5 tons. **Dry weight: 1451.5 kg **Decayed: August 4, 1969 **International Designator
1965-060A

References

External links

* {{Include-NASA 1965 in spaceflight Satellites formerly orbiting Earth Spacecraft launched by Saturn rockets Satellite constellations NASA programs