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 . Space History News - People and events in development of space travel Space History News - People and events in development of space travel Space History News - People and events in development of space travel  

Space History for April 11

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Race To Space
Someone will win the prize...
               ... but at what cost?
Visit to find out more!

Died, Marin Getaldić (Marino Ghetaldi) - Croat physicist and astronomer (conic lens making pioneer, application of algebra in geometry)

Born, William Wallace Campbell, US astronomer, studied stellar motions, director of Lick Observatory

Died, Heinrich Schwabe, German astronomer, discovered the 11 year sunspot cycle

J. Coggia discovered asteroid #187 Lamberta.

Born, Bernhard Schmidt, German optician, invented the Schmidt telescope which corrects optical errors of spherical aberration, coma, and astigmatism

M. Wolf discovered asteroid #530 Turandot.

Born, Frederick "Rick" Hauck (at Long Beach, California, USA), Captain USN, NASA astronaut (STS 7, STS 51-A, STS 26; over 18d 3h total time in spaceflight)

Astronaut Rick Hauck, NASA photo (26 June 1985)
Source: Wikipedia ( unavailable from April 2019)

Born, Anatoli N. Berezovoy (at Enem, Adygei Autonomous Oblast, Russian SFSR), USSR cosmonaut (Salyut 7; over 211d 09h in spaceflgiht) (deceased)

Cosmonauts A. N. Berezovoy (left) and V. V. Lebedev on a "211 days in space" USSR postage stamp (25 April 1983)
Source: Wikipedia

The Ryan X-13 Vertijet became the first jet to take off and land vertically.

F. Borngen discovered asteroid #3539 Weimar.

1970 19:13:00 GMT
NASA launched the ill-fated Apollo 13 mission, intended to be the third mission to carry humans to the surface of the Moon. However, an explosion en-route to the Moon caused the mission to be aborted.

Apollo 13 (AS 508) consisted of the Command and Service Module (CSM) "Odyssey" and the Lunar Module (LM) "Aquarius." The flight was launched on 11 April 1970, intended to be the third mission to carry humans to the surface of the Moon, but an explosion of one of the oxygen tanks and resulting damage to other systems resulted in the mission being aborted before the planned Lunar landing could take place. The crew, commander James A. Lovell, Jr., Command Module pilot John L. Swigert, Jr., and Lunar Module pilot Fred W. Haise Jr., were returned safely to Earth on 17 April 1970.

The purposes of the Apollo 13 mission were (1) to explore the hilly upland Fra Mauro region of the Moon, (2) to perform selenological inspection, survey, and sampling of material in the Fra Mauro formation, (3) to deploy and activate an Apollo Lunar Surface Experiments Package (ALSEP), (4) to further develop man's capability to work in the Lunar environment, and (5) to obtain photographs of candidate Lunar exploration sites. These goals were to be carried out from a near-circular Lunar orbit and on the Lunar surface at 3 deg S latitude, 17 deg W longitude. Although the planned mission objectives were not realized, a limited amount of photographic data was obtained. Lovell was a Navy captain on his fourth spaceflight (he'd flown previously on Gemini 7, Gemini 12, and Apollo 8), Haise and Swigert were both civilians on their first spaceflights.

Apollo 13 was launched at 19:13:00 UT (02:13:00 p.m. EST) from pad 39A at the Kennedy Space Center, Florida. During the second stage boost, the center engine of the S-II stage cut off 132 seconds early, causing the remaining four engines to burn 34 seconds longer than normal. The velocity after the S-II burn was still lower than planned by 68 m/sec, so the S-IVB orbital insertion burn at 19:25:40 was 9 seconds longer than planned. Translunar injection took place at 21:54:47 UT, CSM/S-IVB separation at 22:19:39 UT, and CSM-LM docking at 22:32:09 UT. After separation from the Apollo spacecraft, the S-IVB auxilliary propulsive system burned at 01:13 UT on 12 April for 217 seconds to put the S-IVB into a Lunar impact trajectory. (It impacted the Lunar surface on 14 April 1970.) The Apollo astronauts made a 3.4 second mid-course correction burn at 01:27 UT on 13 April.

A television broadcast was made from Apollo 13 from 02:24 UT to 02:59 UT on 14 April and a few minutes later, at 03:06:18 UT, Jack Swigert turned the fans on to stir oxygen tanks 1 and 2 in the Service Module. Wires which had been damaged during pre-flight testing in the Beech-built oxygen tank number 2 shorted, and the Teflon insulation caught fire. The fire spread within the tank, raising the pressure until at 3:07:53 UT on 14 April (10:07:53 EST 13 April; 55:54:53 mission elapsed time), oxygen tank number 2 exploded, damaging oxygen tank number 1 and the interior of the Service Module, and blowing off the bay number 4 cover. (See a transcript of the events from 2.5 minutes before the accident to about 5 minutes after.) With the oxygen stores depleted, the Command Module was unusable, the mission had to be aborted, and the crew transferred to the Lunar Module and powered down the Command Module.

At 08:43 UT, a mid-course maneuver (11.6 m/s delta V) was performed using the Lunar Module descent propulsion system (LMDPS) to place the spacecraft on a free-return trajectory which would take it around the Moon on a path that took the astronauts farther from Earth than any humans had ever been before and return it to Earth, targeted at the Indian Ocean at 03:13 UT 18 April. After rounding the Moon, another LMDPS burn at 02:40:39 UT 15 April for 263.4 seconds produced a differential velocity of 262 m/s, and shortened the estimated return time to 18:06 UT 17 April, with splashdown in the mid-Pacific. To conserve power and other consumables, the Lunar Module was powered down except for environmental control, communications, and telemetry, and passive thermal control was established. At 04:32 UT on 16 April, a 15 second LMDPS burn at 10% throttle produced a 2.3 m/s velocity decrease and raised the entry flight path angle to -6.52 degrees. Following this, the crew partially powered up the CSM. On 17 April at 12:53 UT, a 22.4 second LMDPS burn put the flight path entry angle at -6.49 degrees.

The Service Module, which had been kept attached to the Command Module to protect the heat shield, was jettisoned on 17 April at 13:15:06 UT, and the crew took photographs of the damage. The Command Module was powered up, and the Lunar Module was jettisoned at 16:43:02 UT. Any parts of the Lunar Module which survived atmospheric re-entry, including the SNAP-27 generator, planned to power the ALSEP apparatus on the Lunar surface and containing 3.9 kg of plutonium, fell into the Pacific Ocean northeast of New Zealand. Apollo 13 splashed down in the Pacific Ocean on 17 April 1970 at 18:07:41 UT (1:07:41 p.m. EST) after a mission elapsed time of 142 hours, 54 minutes, 41 seconds. The splashdown point was 21 deg 38 min S, 165 deg 22 min W, southeast of American Samoa and 6.5 km (4 miles) from the recovery ship USS Iwo Jima.

On 13 June 1970, the Apollo 13 Accident Review Board published the results of its investigation. The explosion was found to have been caused by a bare-wire heating element within the fuel cell liquid oxygen tank. The element itself had burned off its insulation through a combination of unimplemented specification changes early in the program, coupled with unauthorized procedures during ground testing.

The Apollo 13 Command Module "Odyssey" is now on display at the Kansas Cosmosphere and Space Center, Hutchinson, Kansas.

A suspected thruster malfunction caused the USSR Salyut 2 space station to tumble out of control, resulting in four solar panels being torn off and all power to the station being lost.

The Salyut 2 space station, launched 4 April 1973, was designed for scientific research and testing of onboard systems and units. Salyut 2 was intended for service as a space station for experiments and observations. On 11 April 1973, a suspected thruster problem caused craft to tumble out of control, resulting in four solar panels being torn loose from the space station, and cutting off all power to the space station. The craft reentered the Earth's atmosphere 28 May 1973.

E. F. Helin and G. Grueff discovered asteroid #3101 Goldberger.

NASA's Viking 2 lander was turned off on the surface of Mars when its batteries failed.

The Viking project consisted of launches of two separate spacecraft to Mars, Viking 1, launched on 20 August 1975, and Viking 2, launched on 9 September 1975. Each spacecraft consisted of an orbiter and a lander. After orbiting Mars and returning images used for landing site selection, the orbiter and lander detached and the lander entered the Martian atmosphere and soft-landed at the selected site. The orbiters continued imaging and other scientific operations from orbit while the landers deployed instruments on the surface. The fully fueled orbiter-lander pair had a mass of 3530 kg. After separation and landing, the lander had a mass of about 600 kg and the orbiter 900 kg. The lander was encased in a bioshield at launch to prevent contamination by terrestrial organisms.

Following launch and a 333 day cruise to Mars, the Viking 2 Orbiter began returning global images of Mars prior to orbit insertion. The orbiter was inserted into a 1500 x 33,000 km, 24.6 hr Mars orbit on 7 August 1976 and trimmed to a 27.3 hr site certification orbit with a periapsis of 1499 km and an inclination of 55.2 degrees on 9 August. Imaging of candidate sites was begun and the landing site was selected based on these pictures and the images returned by the Viking 1 Orbiter. The lander and its aeroshell separated from the orbiter on 3 September 19:39:59 UT. At the time of separation, the lander was orbiting at about 4 km/s. After separation rockets fired to begin lander deorbit. After a few hours, at about 300 km altitude, the lander was reoriented for entry. The aeroshell with its ablatable heat shield slowed the craft as it plunged through the atmosphere. During this time, entry science experiments were performed. At 6 km altitude at about 250 m/s the 16 m diameter lander parachutes were deployed. Seven seconds later the aeroshell was jettisoned, and 8 seconds after that the three lander legs were extended. In 45 seconds the parachute had slowed the lander to 60 m/s. At 1.5 km altitude, retro-rockets were ignited and fired until landing 40 seconds later at about 2.4 m/s. The landing rockets used an 18 nozzle design to spread the hydrogen and nitrogen exhaust over a wide area. It was determined that this would limit surface heating to no more than 1 degree C and that no more than 1 mm of the surface material would be stripped away.

The Viking 2 Lander touched down about 200 km west of the crater Mie in Utopia Planitia at 48.269 deg N latitude and 225.990 deg W longitude at a reference altitude of 4.23 km relative to a reference ellipsoid with an equatorial radius of 3397.2 km and a flatness of 0.0105 (48.039 deg N, 226.032 deg W planetographic) at 3 September 1976 22:58:20 UT (9:49:05 AM local Mars time). Approximately 22 kg of propellants were left at landing. Due to radar misidentification of a rock or highly reflective surface, the thrusters fired an extra time 0.4 seconds before landing, cracking the surface and raising dust. The lander settled down with one leg on a rock, tilted at 8.2 degrees. The cameras began taking images immediately after landing. The Viking 2 Lander operated on the surface for 1281 Mars days and was turned off on 11 April 1980 when its batteries failed.

The Viking 2 Orbiter's operating plan called for the structure connecting the orbiter and lander (the bioshield) to be ejected after separation, but because of problems with the separation the bioshield remained attached to the orbiter. The orbit inclination was raised to 75 degrees on 30 September 1976. The orbiter primary mission ended at the beginning of solar conjunction on 8 November 1976. The extended mission commenced on 14 December 1976 after solar conjunction. On 20 December 1976 the periapsis was lowered to 778 km and the orbit inclination raised to 80 degrees. Operations included close approaches to Deimos in October 1977. The periapsis was lowered to 300 km and the period changed to 24 hours on 23 October 1977. The orbiter developed a leak in its propulsion system that vented its attitude control gas. It was placed in a 302 x 33176 km orbit and turned off on 25 July 1978 after returning almost 16,000 images in 706 orbits around Mars.

The primary objectives of the Viking orbiters were to transport the landers to Mars, perform reconnaissance to locate and certify landing sites, act as a communications relays for the landers, and to perform their own scientific investigations. The orbiter, based on the earlier Mariner 9 spacecraft, was an octagon approximately 2.5 m across. The total launch mass was 2328 kg, of which 1445 kg were propellant and attitude control gas. The eight faces of the ring-like structure were 0.4572 m high and were alternately 1.397 and 0.508 m wide. The overall height was 3.29 m from the lander attachment points on the bottom to the launch vehicle attachment points on top. There were 16 modular compartments, 3 on each of the 4 long faces and one on each short face. Four solar panel wings extended from the axis of the orbiter, the distance from tip to tip of two oppositely extended solar panels was 9.75 m. Power was provided by eight 1.57 x 1.23 m solar panels, two on each wing, were made up of a total of 34,800 solar cells that produced 620 W of power at Mars. Power was also stored in 2 nickel-cadmium 30-amp-hr batteries.

The orbiter's main propulsion unit was mounted above the orbiter bus. Propulsion was furnished by a bipropellant (monomethyl hydrazine and nitrogen tetroxide) liquid-fueled rocket engine which could be gimballed up to 9 degrees. The engine was capable of 1323 N thrust, translating to a delta-V of 1480 m/s. Attitude control was achieved by 12 small compressed-nitrogen jets. An acquisition Sun sensor, a cruise Sun sensor, a Canopus star tracker and an inertial reference unit consisting of 6 gyroscopes allowed three-axis stabilization. Two accelerometers were also on board. Communications were accomplished through a 20-W S-band (2.3 GHz) transmitter and 2 20-W TWTA's. An X-band (8.4 GHz) downlink was also added specifically for radio science and to conduct communications experiments. Uplink was via S-band (2.1 GHz). A 2-axis steerable high-gain parabolic dish antenna with a diameter of approximately 1.5 m was attached at one edge of the orbiter base, and a fixed low-gain antenna extended from the top of the bus. Two tape recorders were each capable of storing 1280 Mbits. A 381 MHz relay radio was also available. Temperature control was achieved by multilayer insulation, thermally activated louvers, and electrical heaters.

Scientific instruments for conducting imaging, atmospheric water vapor, and infrared thermal mapping were enclosed in a temperature controlled, pointable scan platform extending from the base of the orbiter. The scientific instrumentation had a total mass of approximately 72 kg. Radio science investigations were also done using the spacecraft transmitter. Command processing was done by two identical and independent data processors, each with a 4096-word memory for storing uplink command sequences and acquired data.

The lander consisted of a 6-sided aluminum base with alternate 1.09 m and 0.56 m long sides, supported on three extended legs attached to the shorter sides. The leg footpads formed the vertices of an equilateral triangle with 2.21 m sides when viewed from above, with the long sides of the base forming a straight line with the two adjoining footpads. Instrumentation was attached to the top of the base, elevated above the surface by the extended legs. Power was provided by two radioisotope thermal generator (RTG) units containing plutonium 238 affixed to opposite sides of the lander base and covered by wind screens. Each generator was 28 cm tall, 58 cm in diameter, had a mass of 13.6 kg and provided 30 W continuous power at 4.4 volts. Four wet-cell sealed nickel-cadmium 8-amp-hour, 28 volt rechargeable batteries were also onboard to handle peak power loads.

The lander's propulsion was provided for deorbit by a monopropellant hydrazine (N2H4) rocket with 12 nozzles arranged in four clusters of three that provided 32 N thrust, giving a delta-V of 180 m/s. These nozzles also acted as the control thrusters for translation and rotation of the lander. Terminal descent and landing was achieved by three (one affixed on each long side of the base, separated by 120 degress) monopropellant hydrazine engines. The engines had 18 nozzles to disperse the exhaust and minimize effects on the ground, were throttleable from 276 N to 2667 N. The hydrazine was purified to prevent contamination of the Martian surface. The lander carried 85 kg of propellant at launch, contained in two spherical titanium tanks mounted on opposite sides of the lander beneath the RTG windscreens, for a total launch mass of 657 kg. Control was achieved through the use of an inertial reference unit, four gyros, an aerodecelerator, a radar altimeter, a terminal descent and landing radar, and the control thrusters.

Lander communications were accomplished through a 20 W S-band transmitter and two 20 W TWTA's. A 2-axis steerable high-gain parabolic antenna was mounted on a boom near one edge of the lander base. An omnidirectional low-gain S-band antenna also extended from the base. Both these antennae allowed for communication directly with the Earth. A UHF (381 MHz) antenna provided a one-way relay to the orbiter using a 30 W relay radio. Data storage was on a 40 Mbit tape recorder, and the lander computer had a 6000 word memory for command instructions.

The lander carried instruments to achieve the primary scientific objectives of its mission: to study the biology, chemical composition (organic and inorganic), meteorology, seismology, magnetic properties, appearance, and physical properties of the Martian surface and atmosphere. Two 360-degree cylindrical scan cameras were mounted near one long side of the base. From the center of this side extended the sampler arm, with a collector head, temperature sensor, and magnet on the end. A meteorology boom, holding temperature, wind direction, and wind velocity sensors extended out and up from the top of one of the lander legs. A seismometer, magnet and camera test targets, and magnifying mirror are mounted opposite the cameras, near the high-gain antenna. An interior environmentally controlled compartment held the biology experiment and the gas chromatograph mass spectrometer. The X-ray flourescence spectrometer was also mounted within the structure. A pressure sensor was attached under the lander body. The scientific payload had a total mass of approximately 91 kg.

See also the Viking 2 Lander page.

1983 22:39:00 GMT
NASA launched RCA-SATCOM 6, owned by GE American Communications, into geosynchronous orbit.

RCA-SATCOM 6 was the seventh in a series of RCA-GLOBCOM commercial communications satellites, owned by GE American Communications, Inc. It was launched into a geosynchronous orbit from Cape Canaveral, Florida on 11 April 1983. The Delta rocket performed nominally, placing the spacecraft and its apogee boost motor (ABM) into the desired transfer orbit that permitted the propulsion systems to meet the mission's objectives.

1984 10:50:00 GMT
USSR Soyuz T-10 returned to Earth from the Salyut 7 space station, 100 miles east of Dzehezkazgan, with the crew of Soyuz T-11 aboard.

Halley's Comet made its closest approach to Earth during the current orbit, approaching within 63 million km.

1991 06:55:29 PDT (GMT -7:00:00)
NASA's STS 37 (Atlantis 8, 39th Shuttle mission) landed after carrying the Gamma Ray Observatory (GRO) to orbit.

STS 37 was launched 5 April 1991 after a brief delay due to low level clouds in area. Its primary payload, the Gamma Ray Observatory (GRO), the heaviest shuttle-launched payload to date, was deployed on flight day three (7 April 1991). The GRO high-gain antenna failed to deploy on command; it was finally freed and manually deployed by Ross and Apt during an unscheduled contingency space walk, the first since April 1985. The following day, the two astronauts performed the first scheduled space walk since November 1985 to test means for astronauts to move themselves and equipment about while maintaining the Space Station Freedom, then still in the planning stage. Several times during the flight, Atlantis passed within view of the Mir station. The crew attempted to contact their Soviet conterparts via ham radio, but were unsuccessful.

The GRO science instruments were the Burst and Transient Source Experiment (BATSE), Imaging Compton Telescope (COMPTEL), Energetic Gamma Ray Experiment Telescope (EGRET) and Oriented Scintillation Spectrometer Experiment (OSSEE). Secondary payloads on STS 37 included Crew and Equipment Translation Aids (CETA), which involved a scheduled six hour space walk by astronauts Ross and Apt (see above); Ascent Particle Monitor (APM); Shuttle Amateur Radio Experiment II (SAREX II); Protein Crystal Growth (PCG); Bioserve/Instrumentation Technology Associates Materials Dispersion Apparatus (BIMDA); Radiation Monitoring Equipment III (RME III); and the Air Force Maui Optical Site (AMOS) experiment.

STS 37 ended on 11 April 1991 when Atlantis landed on revolution 93 on Runway 33, Edwards Air Force Base, California. Rollout distance: 6,364 feet. Rollout time: 54 seconds. Launch weight: 255,824 pounds. Landing weight: 190,098 pounds. Orbit altitude: 248 nautical miles. Orbit inclination: 28.45 degrees. Mission duration: five days, 23 hours, 32 minutes, 44 seconds. Miles Traveled: 2.5 million. The landing was originally scheduled for 10 April, but was delayed one day due to weather conditions at Edwards and KSC. The orbiter was returned to Kennedy Space Center on 18 April 1991.

The flight crew for STS 37 was: Steven R. Nagel, Commander; Kenneth D. Cameron, Pilot; Jerry L. Ross, Mission Specialist 1; Jay Apt, Mission Specialist 2; Linda M. Godwin, Mission Specialist 3.

STS 56 astronauts deployed the SPARTAN-201 experiment platform into orbit for two days of independent operation.

The first launch attempt of STS 56 on 6 April 1993 was halted at T-11 seconds by orbiter computers when instrumentation on the liquid hydrogen high point bleed valve in the main propulsion system indicated off instead of on. Later analysis indicated the valve was properly configured; 48 hour scrub turnaround procedures were then implemented. The final countdown on 8 April 1993 proceeded smoothly.

The primary payload for STS 56 was the second flight of the Atmospheric Laboratory for Applications and Science (ATLAS-2), designed to collect data on the relationship between the Sun's energy output and the Earth's middle atmosphere, and how these factors affect the ozone layer. It included six instruments mounted on a Spacelab pallet in the cargo bay, with the seventh mounted on the wall of the bay in two Get Away Special (GAS) canisters. Atmospheric instruments included the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment, the Millimeter Wave Atmospheric Sounder (MAS), and the Shuttle Solar Backscatter Ultraviolet/A (SSBUV/A) spectrometer (on the cargo bay wall). Solar science instruments were the Solar Spectrum Measurement (SOLSPEC) instrument, the Solar Ultraviolet Irradiance Monitor (SUSIM), and the Active Cavity Radiometer (ACR) and Solar Constant (SOLCON) experiments.

ATLAS-2 is one element of NASA's Mission to Planet Earth program. All seven ATLAS-2 instruments first flew on ATLAS-I during STS-45, and were scheduled to fly a third time in late 1994.

On 11 April, the crew used the remote manipulator arm to deploy the Shuttle Point Autonomous Research Tool for Astronomy-201 (SPARTAN-201), a free-flying science instrument platform designed to study velocity and acceleration of the Solar wind and observe the Sun's corona. Collected data was stored on tape for playback after return to Earth. SPARTAN-201 was retrieved on 13 April.

The crew also made numerous radio contacts to schools around the world using the Shuttle Amateur Radio Experiment II (SAREX II), including brief radio contact with the Russian Mir space station, the first such contact between Shuttle and Mir using amateur radio equipment.

The other cargo bay payload was the Solar Ultraviolet Experiment (SUVE), sponsored by Colorado Space Grant Consortium and located in a Get Away Special (GAS) canister on the cargo bay wall.

The middeck payloads were the Commercial Materials Dispersion Apparatus Instrumentation Technology Associates Experiment (CMIX), the Physiological and Anatomical Rodent Experiment (PARE), Space Tissue Loss (STL-1) experiment, the Cosmic Ray Effects and Activation Monitor (CREAM) experiment, the Hand-held, Earth-oriented, Real-time, Cooperative, User-friendly, Location-targeting and Environmental System (HERCULES), Radiation Monitoring Equipment III (RME III), and an Air Force Maui Optical Site (AMOS) calibration test.

STS 56 ended on 17 April 1993 when Discovery landed on revolution 148 on Runway 33, Kennedy Space Center, Florida. Rollout distance: 9,530 feet (2,905 meters). Rollout time: 63 seconds. Launch weight: 236,659 pounds. Landing weight: 206,855 pounds. Orbit altitude: 160 nautical miles. Orbit inclination: 57 degrees. Mission duration: nine days, six hours, eight minutes, 24 seconds. Miles Traveled: 3.9 million. The landing originally set for 16 April at Kennedy Space Center was waved off due to weather.

The flight crew for STS 56 was: Kenneth D. Cameron, Commander; Stephen S. Oswald, Pilot; C. Michael Foale Ph.D., Mission Specialist 1; Kenneth D. Cockrell, Mission Specialist 2; Ellen Ochoa, Mission Specialist 3.

2005 13:35:00 GMT
The US Air Force launched the Air Force Research Laboratory's Experimental Satellite System-11 (XSS-11) to study autonomous satellite rendevous technology.

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