Germans operationally test fired over 100 V-2's from Blizna, Poland, launching 10 on one day, only a small number of which were fully successful. References: 17 .

Council of Chief designers approval to proceed with development of R-7. References: 89 .

Seventeen years after his arrest, and after ten years as head of the Soviet rocketry program, Korolev's arrest and imprisonment during Stalin's purges are rescinded.

Korolev revised his earlier, disapproved plan with one that now included participation of his rivals, Chelomei and Yangel.

KH-4; film capsule recovered 3.1 days later. Slight corona static on film. References: 1 , 2 , 5 , 6 .

Surveyor 1 soft landed on the moon in the Ocean of Storms and began transmitting the first of more than 11,150 clear, detailed television pictures to Jet Propulsion Laboratory's Deep Space Facility, Goldstone, Calif. The landing sequence began 3,200 kilometers above the moon with the spacecraft traveling at a speed of 9,700 kilometers per hour. The spacecraft was successfully slowed to 5.6 kilometers per hour by the time it reached 4-meter altitude and then free-fell to the surface at 13 kilometers per hour. The landing was so precise that the three footpads touched the surface within 19 milliseconds of each other, and it confirmed that the lunar surface could support the LM. It was the first U.S. attempt to soft land on the moon. References: 1 , 2 , 5 , 6 , 16 , 278 .

Investigation of the upper atmosphere and outer space. References: 1 , 2 , 5 , 6 , 99 .

The first spacecraft to orbit another planet. The Mariner Mars 71 mission was planned to consist of two spacecraft on complementary missions. Mariner 8 was to map 70 % of the Martian surface and Mariner 9 was to study temporal changes in the Martian atmosphere and on the Martian surface. The launch failure of Mariner 8 forced Mariner 9 to combine the mission objectives of both. For the survey portion of the mission, the planetary surface was to be mapped with the same resolution as planned for the original mission, although the resolution of pictures of the polar regions would be decreased due to the increased slant range. The variable features experiments were changed from studies of six given areas every 5 days to studies of smaller regions every 17 days. Mariner 9 was launched on a direct trajectory to Mars. Separation from the booster occurred at 22:36 GMT. The four solar panels were deployed at 22:40 GMT. The sensors locked onto the Sun at 23:16, shortly after the spacecraft left the Earth's shadow and Canopus acquisition was achieved at 02:26 GMT 31 May. A planned midcourse maneuver was executed on 5 June. Mariner 9 arrived at Mars on 14 November 1971 after a 167 day flight. A 15 minute 23 second rocket burn put the spacecraft into Mars orbit. The insertion orbit had a periapsis of 1398 km and a period of 12 hr, 34 min. Two days later a 6 second rocket burn changed the orbital period to just under 12 hours with a periapsis of 1387 km. A correction trim maneuver was made on 30 December on the 94th orbit which raised the periapsis to 1650 km and changed the orbital period to 11:59:28 so that synchronous data transmissions could be made to the Goldstone 64-m DSN antenna.

Imaging of the surface of Mars by Mariner 9 was delayed by a dust storm which started on 22 September 1971 in the Noachis region. The storm quickly grew into one of the largest global storms ever observed on Mars. By the time the spacecraft arrived at Mars no surface details could be seen except the summits of Olympus Mons and the three Tharsis volcanoes. The storm abated through November and December and normal mapping operations began. The spacecraft gathered data on the atmospheric composition, density, pressure, and temperature and also the surface composition, temperature, gravity, and topography of Mars. A total of 54 billion bits of scientific data were returned, including 7329 images covering the entire planet. After depleting its supply of attitude control gas, the spacecraft was turned off on 27 October 1972. Mariner 9 was left in an orbit which should not decay for at least 50 years, after which the spacecraft will enter the Martian atmosphere.

The Mariner 9 mission resulted in a global mapping of the surface of Mars, including the first detailed views of the martian volcanoes, Valles Marineris, the polar caps, and the satellites Phobos and Deimos. It also provided information on global dust storms, the gravity field as well as evidence for surface aeolian activity. References: 1 , 2 , 5 , 6 , 278 , 296 .

Meteorological Rocket. References: 98 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Application Technology Satellite; experimental commsat. - Also conducted Cesium ion engine test. References: 1 , 2 , 5 , 6 .

Zenit-2M (area survey photo reconnaissance) satellite used for earth resources studies as part of 'Gektor-Priroda' project. Investigation of the natural resources of the earth in the interests of various branches of the national economy of the USSR and international cooperation. References: 1 , 2 , 6 , 103 .

Start Enterprise (OV-101)/ ET mated vertical ground vibration test, MSFC References: 15 .

Deliver ET used in mated vertical ground vibration test from MSFC to Martin Marietta for refurbishment References: 15 .

Ocean monitoring. References: 1 , 2 , 5 , 6 .

Military navigation satellite. Replaced Cosmos 1447. References: 1 , 2 , 5 , 6 .

Investigation of the upper atmosphere and outer space. References: 1 , 2 , 5 , 6 , 114 .

Unmanned resupply vessel to Mir. Docked with Mir on 1 Jun 1991 09:44:37 GMT. Undocked on 15 Aug 1991 22:16:59 GMT. Destroyed in reentry on 16 Aug 1991 06:56:32 GMT. Total free-flight time 2.43 days. Total docked time 75.52 days. References: 1 , 2 , 6 , 275 .

Multi-Spectral Scanner installed. References: 66 .

Also known as Chinastar 1; comsat to serve China, India, Korea and Southeast Asia with 18 C-band and 20 Ku-band transponders. Operated by the China Orient Telecommunications Satellite Company, part of the Chinese telecommunications ministry. Zhongwei 1 and the CZ-3B's final liquid hydrogen upper stage were placed in an initial supersynchronous 216 x 85,035 km x 24.4 deg transfer orbit. Geostationary at 87.6 degrees E.

On May 30 at 02:56 GMT Tammy Jernigan and Dan Barry entered the payload bay of space shuttle Discovery from the tunnel adapter hatch. During the space walk they transferred equipment to the exterior of the station.