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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 May 25

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

Died, Gemma Frisius, geographer, astronomical instrument maker, first described triangulation for surveying and using an accurate clock to determine longitude

Born (6 June N.S. date), Aleksandr Lyapunov, Russian mathemetican, mechanician and physicist (stability theory of a dynamical system, mathematical physics and probability theory)

Born, Igor Sikorsky, helicopter pioneer

Igor Ivanovich Sikorsky (25 May 1889 - 26 October 1972) was a Ukrainian-born pioneer of aviation who designed the first four-engine airplanes and the first modern helicopter.

Igor Sikorsky was born in Kiev, Ukraine and studied at the Naval War College in St. Petersburg. He emigrated from the Russia to the United States in 1919, at the age of 30, fleeing the Bolshevik regime installed after the October Revolution.

Sikorsky's early work included the construction, as chief engineer, of the first four-motor aircraft; he acted as the test pilot for its inaugural flight, on 13 May 1913. His planes were used by the Russian government as bombers in World War I.

In 1923, in the US, he formed the Sikorsky Aero Engineering Company, which was purchased by and became a subsidiary of United Aircraft (itself now a part of United Technologies Corporation). The company manufactured flying boats such as the Sikorsky S42, used by Pan Am for trans-atlantic flights and known as Pan Am Clippers.

Sikorsky had experimented with helicopter type flying machines while in Russia, and brought his work to fruition on 24 May 1940 when he performed the first successful helicopter flight, in a machine with a single three-blade rotor powered by a 75 horsepower (56 kW) engine, the Vought-Sikorsky 300.

M. Wolf discovered asteroid #874 Rotraut.

V. Albitzkij discovered asteroid #1030 Vitja.

US Army Air Corps Lt. James "Jimmy" Doolittle flew the first "outside" loop over McCook Field, near Dayton, Ohio in a Curtiss P-1B Hawk. Some scientists had predicted outside loops (inverted loops) would be fatal.

Born, Georgi Mikhailovich Grechko (at Leningrad, Russian SFSR), Soviet cosmonaut (Salyut 4, Salyut 6, Salyut 7; over 134d 20.5h total time in spaceflight) (deceased)

Soviet cosmonaut Georgy Grechko, 17 May 2011
Photo by Serge Serebro, Vitebsk Popular News
Source: Wikipedia

C. Jackson discovered asteroid #1244 Deira.

Died, Sir Frank Watson Dyson, English Astronomer Royal (proved Einstein right about light being bent by gravity)

C. Jackson discovered asteroid #1393 Sofala.

British Interplanetary Society member and science fiction writer Arthur C. Clark proposed relay satellites in geosynchronous orbit in a typed paper circulated to members of the British Interplanetary Society.

President John F. Kennedy made a speech before Congress urging the US to fly a man to the Moon.

President John F. Kennedy started the US Lunar landing program in his second State of the Union Message before Congress, saying, "I believe this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to Earth..."

Following Gagarin's flight and the Bay of Pigs failure, Kennedy announced the objective of landing an American on the Moon by end of the decade. In his second State of the Union Message, President Kennedy said: "With the advice of the Vice President, who is Chairman of the National Space Council, we have examined where we (United States) are strong and where we are not, where we may succeed and where we may not. . . . Now is the time to take longer strides - time for a great new American enterprise - time for this Nation to take a clearly leading role in space achievement which in many ways may hold the key to our future on Earth." President Kennedy set forth an accelerated space program based upon the long-range national goals of landing a man on the Moon and returning him safely to Earth; early development of the Rover nuclear rocket; speeding up the use of Earth satellites for worldwide communications; and providing "at the earliest possible time a satellite system for worldwide weather observation." An additional $549 million was requested for NASA over the new administration March budget requests; $62 million was requested for the Department of Defense for starting development of a solid-propellant booster of the Nova class.

1961 20:16:00 GMT
NASA launched X-15A Mach 5, SAS, Aero Test mission # 37 in which civilian pilot Joe Walker achieved a maximum speed of 3307 mph (5322 kph, Mach 4.95) and a maximum altitude of 107,500 ft (32.766 km, 20.360 mi).

1965 07:41:00 GMT
NASA launched the Pegasus 2 meteoroid detection satellite.

Pegasus 2 was a meteoroid detection satellite launched 25 May 1965. The Saturn I launch vehicle (SA-8) placed the spacecraft, protected by a boilerplate Apollo Model 4 CSM (BP-26), into a 740-by-509-km (460-by-316-mi) orbit. Once in orbit, the dummy CSM was jettisoned. Pegasus 2, still attached to the second stage of the launch vehicle, then deployed its 29-m (96-ft) winglike panels. Within several hours, the device began registering meteoroid hits.

Launch of Pegasus 2, NASA photo
Source: NSSDCA Master Catalog

1965 18:12:00 GMT
NASA launched X-15A IFDS/MIT/RAS Mod Technology/Test mission # 133 in which Air Force pilot Milt Thompson reached a maximum speed of 3418 mph (5501 kph, Mach 4.87) and a maximum altitude of 179,800 ft (54.803 km, 34.053 mi).

Born, John Daniel Olivas (at North Hollywood, California, USA), NASA astronaut (STS 117, STS 128; over 27d 17h total time in spaceflight)

Astronaut John Olivas, NASA photo (18 September 2006)
Source: Wikipedia ( killed 25 Feb 2021)

NASA rolled the first full-scale Apollo Saturn V launch vehicle out of the Vehicle Assembly Building.

AS-500-F, the Pathfinder first full-scale Apollo Saturn V launch vehicle and spacecraft combination, was rolled out from Kennedy Space Center's Vehicle Assembly Building to the launch pad, for use in verifying launch facilities, training crews, and developing test procedures. The 111-meter, 227,000-kilogram vehicle was moved by a diesel-powered steel-link-tread crawler-transporter exactly five years after President John F. Kennedy asked the United States to commit itself to a manned Lunar landing within the decade. Meanwhile, the schedule for Saturn V was threatened by continued problems in development of the S-II stage (inability to get sustained 350 second burns without instrumentation failures, shutoffs, minor explosions).

1966 13:55:00 GMT
NASA launched Explorer 32 (Atmosphere Explorer-B) from Cape Kennedy, Florida, an aeronomy satellite designed to directly measure temperatures, composition, densities, and pressures in the upper atmosphere on a global basis.

Born, Dmitri Yurievich Kondratiyev (at Irkutsk, Irkutsk Oblast, Russian SFSR), Colonel Russian AF, Russian cosmonaut (ISS 26/27 Commander; over 159d 7.25h in spaceflight)

Cosmonaut Dmitry Kondratyev, ISS 26 engineer, ISS 27 commander, NASA photo (15 Sept 2010)
Source: Wikipedia ( dead 25 Feb 2021)

1973 13:00:00 GMT
NASA launched the Skylab 2 (CSM 116, AS 206) mission, almost identical to the Command and Service Module used for Apollo missions to the Moon, bringing the first crew to the Skylab space station.

Skylab 2, launched 25 May 1973, has been described as an "epic repair mission" which brought NASA's Skylab orbital laboratory into working order. Among the flight's events are such great moments as astronaut Pete Conrad being "flung through space by the whiplash" after heaving on a jammed solar panel just as the debris constraining it gave way, and deployment of a lightweight solar shield, developed in Houston in one week, which brought the internal temperatures down to tolerable levels. With this flight, the US again took the manned spaceflight duration record.

The spacecraft was almost identical to the Command and Service Module (CSM) used for the Apollo Moon missions. Modifications were made to accomodate the long duration Skylab missions, and to allow the spacecraft to remain semi-dormant while docked to the Skylab cluster. The mission of the spacecraft was to ferry a crew of three to the Skylab complex and return them to Earth.

The basic flight objectives were: operation of the orbital workshop as a habitable space structure for up to 28 days; acquisition of medical data on the crew for use in extending the duration of manned flight; and in-flight experiments. The mission was considered successful: The crew made repairs to the workshop damaged during launch (Skylab parasol), although they experienced some difficulty in performing the docking procedure.

Skylab 2, consisting of a modified Apollo CSM payload and a Saturn IB launch vehicle, was inserted into a 357 by 156 km Earth orbit approximately 10 minutes after liftoff. During the six hours following orbit insertion, four maneuvers placed the CSM into a 424 by 415 km orbit for rendezvous with the Skylab Orbital Workshop (OWS). Normal rendezvous sequencing led to stationkeeping during the fifth revolution, followed by a flyaround inspection of the damage to the OWS. The crew provided a verbal description of the damage in conjunction with 15 minutes of television coverage. The solar array system wing (beam) 2 was completely missing. The solar array system wing (beam) 1 was slightly deployed, restrained by a fragment of the meteoroid shield. Large sections of the meteoroid shield were missing. Following the flyaround inspection, the CSM soft-docked with the OWS at 5:56 pm EDT to plan the next activities. At 6:45 pm EDT, the CSM undocked and extravehicular activity was initiated to deploy the beam 1 solar array. The attempt failed. Frustration of the crew was compounded when eight attempts were required to achieve hard docking with the OWS. The hard dock was made at 11:50 pm EDT, terminating a Skylab 2 first day crew work period of 22 hours.

After the failed attempt to deploy the stuck solar panel, the astronauts set up the "parasol" as a replacement sunshade. The "fix" worked, and temperatures inside dropped low enough so that the crew could enter. Two weeks later, Conrad and Kerwin conducted a space-walk, and after a struggle, were able to free the stuck solar panel and begin electricity flowing to their new "home."

For nearly a month, astronauts Charles "Pete" Conrad Jr. (Commander), Paul J. Weitz (Pilot), and Joseph P. Kerwin (Science Pilot) made further repairs to the OWS, conducted medical experiments, gathered solar and Earth science data, and used some 29,000 frames of film with a total of 392 hours of experiments. They spent 26 days, 16 hours working in the OWS before returning to Earth on 22 June 1973 (total flight time 28+ days: 672 hours 49 minutes 49 seconds). Skylab 2 splashed down in the Pacific Ocean 9.6 km from the recovery ship, USS Ticonderoga.

The Skylab 2 astronauts spent 28 days in space, which doubled the previous US record. The mission set the records for the longest duration manned spacelight, greatest distance travelled, and greatest mass docked in space, and Conrad set the record for most time in space for a single astronaut.

The Skylab2 Command Module is displayed at the Naval Aviation Museum, Pensacola, Florida.

See also NASA's Skylab Operations Summary at the Internet Archive

1977 11:02:00 GMT
USSR launched Cosmos 911 into orbit as part of a 6-satellite Soviet military navigation system.

1982 09:00:00 GMT
USSR launched Cosmos 1369 from Plesetsk, a third generation, high resolution Soviet photo surveillance satellite, "for investigation of the natural resources of the Earth."

1989 08:50:00 GMT
USSR launched Resurs F-01 for investigation of the Earth's natural resources. The satellite carried two passive separable 'Pion' probes to investigate upper atmospheric density, which it relased into independent orbits.

1996 02:05:00 GMT
Russia launched the Gorizont 32 communications satellite from Baikonur, positioned in geosynchronous orbit at 53 deg E in 1996-1999.

2004 12:34:00 GMT
Russia launched Progress M-49 from Baikonur to the International Space Station, an unmanned resupply vessel.

The HiRISE camera on NASA's Mars Reconnaissance Orbiter photographed the Phoenix lander during its parachute descent to Vastitas Borealis.

The Mars Reconnaissance Orbiter (MRO), launched 12 August 2005 on an Atlas V, was designed to orbit Mars over a full Martian year and gather data with six scientific instruments, including a high-resolution imager. The science objectives of the mission are to: characterize the present climate of Mars and its physical mechanisms of seasonal and interannual climate change; determine the nature of complex layered terrain on Mars and identify water-related landforms; search for sites showing evidence of aqueous and/or hydrothermal activity; identify and characterize sites with the highest potential for landed science and sample return by future Mars missions; and return scientific data from Mars landed craft during a relay phase. MRO was planned to return high resolution images, study surface composition, search for subsurface water, trace dust and water in the atmosphere, and monitor weather.

The launch window opened at Kennedy Space Center on 10 August 2005, with launch opportunities available until 5 September. The cruise to Mars took about seven months and included checkouts, calibrations, navigation, and three trajectory correction maneuvers (TCMs). The planned fourth TCM and possible fifth TCM were not required, saving 60 pounds (27 kg) of fuel, usable during MRO's extended mission. On 10 March 2006, MRO reached Mars and performed a Mars orbit insertion maneuver, passing under the southern hemisphere of Mars at an altitude of 370–400 km (230–250 mi) and firing its main engines for about 27 minutes. Signals that the burn had started reached Earth at 21:24 UT (4:24 PM EST) on 10 March. With 6 minutes left in the burn MRO passed behind Mars as seen from Earth. Radio communication resumed when it re-emerged about 30 minutes later.

The 1641 second orbit insertion burn slowed the spacecraft by about one km/sec, leaving it in a 400 x 35000 km polar capture orbit with a 35.5 hour period. The helium pressurization tank was colder than expected, which reduced the pressure in the fuel tank by about 21 kilopascals (3.0 psi). The reduced pressure caused the diminished engine thrust by 2%, but MRO automatically compensated by extending the burn time by 33 seconds. Shortly after insertion, the periapsis (closest approach to Mars) was 426 km (265 mi) from the surface (3,806 km (2,365 mi) from the planet's center). The apoapsis (the farthest distance from Mars) was 44,500 km (27,700 mi) from the surface (47,972 km (29,808 mi) from the planet's center).

Aerobraking was used over the next five months, from 30 March to 30 August 2006, to lower the orbit. MRO fired its thrusters twice more in September 2006 to fine-tune its final, nearly circular science orbit to approximately 250 to 316 km (155 to 196 mi) above the Martian surface (with periapsis over the south pole and apoapsis over the north pole). There are twelve sun-synchronous orbits per day so that the orbiter will always see the ground at 3:00 PM local time at the equator.

The SHARAD radar antennas were deployed on 16 September 2006. All of the scientific instruments were tested and most were turned off prior to the solar conjunction which occurred from 7 October to 6 November 2006. The "primary science phase" began after the conjunction ended.

MRO took its first high resolution image from its science orbit on 29 September 2006, resolving items as small as 90 cm (3 feet) in diameter. On 6 October, NASA released detailed pictures from the MRO of Victoria crater with the Opportunity rover on the rim above it. On 17 November 2006 NASA announced the successful test of the MRO as an orbital communications relay: Using the NASA rover Spirit as the point of origin for the transmission, the MRO acted as a relay for transmitting data back to Earth.

HiRISE continues to return images enabling discoveries regarding the geology of Mars. Among these is the banded terrain observations indicating the presence and action of liquid carbon dioxide (CO2) or water on the surface of Mars in its recent geological past. HiRISE photographed the Phoenix lander during its parachute descent to Vastitas Borealis on 25 May 2008 (sol 990). On 6 August 2012 (sol 2483) the orbiter passed over Gale crater, the landing site of the Mars Science Laboratory mission, during its EDL phase. The HiRISE camera captured an image of the Curiosity rover descending with its backshell and supersonic parachute.

On 3 March 2010, the Mars Reconnaissance Orbiter passed another significant milestone, having transmitted over 100 terabits of data back to Earth, which was more than all other interplanetary probes sent from Earth combined.

Science operations took place nominally from the end of solar conjunction in November 2006 to the start of the next solar conjunction in November 2008, roughly one Martian year. Following the nominal mission, extended science and communications relay missions have been undertaken.

In November 2006, problems began to surface with two MRO instruments: A stepping mechanism in the Mars Climate Sounder (MCS) skipped on multiple occasions, resulting in a field of view that is slightly out of position. By December normal operations of the instrument were suspended, although a mitigation strategy allows the instrument to continue making most of its intended observations. Also, an increase in noise and resulting bad pixels has been observed in several CCDs of the High Resolution Imaging Science Experiment (HiRISE). Operation of the camera with a longer warm-up time has alleviated the issue, but the cause is still unknown and the problem may return. The orbiter continued to experience recurring problems in 2009, including four spontaneous resets, culminating in a four-month shut-down of the spacecraft from August to December. While engineers did not determine the cause of the recurrent resets, they have created new software to help troubleshoot the problem should it recur.

The Mars Reconnaissance Orbiter consists of a main bus, constructed of titanium, carbon composites, and aluminum honeycomb. Extending from the bus are two solar panel wings and a 3 meter high-gain antenna dish. The bus houses the propulsion system, telecommunications, command, guidance, and science instruments. The maximum spacecraft mass was 2180 kg, including 1149 kg of propellants.

Propulsion is provided by a total of 20 thrusters. Six 170N monopropellant (hydrazine) main-engine thrusters were used for the Mars Orbit insertion burn, which used about 70% of the total fuel onboard. Six 22N thrusters are used for trajectory correction maneuvers and eight 0.9N thrusters for pointing. All thrusters are fed from a single propellant tank mounted near the center of the main bus. A pressurant tank is used to force propellant to the motors. Spacecraft control is achieved with the use of reaction wheels and reaction control system thrusters. Navigation and attitude knowledge is determined by 16 Sun sensors, two star tracker cameras, and two inertial measurement units which use accelerometers and gyroscopes.

Two way telecommunications is done via X-band at about 8000 MHz, primarily through the 3 m diameter steerable high-gain dish antenna. Two low-gain Ka-band antennas, mounted on the high-gain dish, are also available for transmission and reception. Two transponders and three TWT amplifiers allow maximum data rates of 6 megabits/sec. Power is provided by the two solar cell array wings mounted on opposite side of the bus. Each array has an area of 10 square meters and contains 3744 solar cells. The panels produce 1000 Watts at Mars which is used to run the equipment directly, and to charge two nickel-hydrogen 50 A-hr, 32-volt batteries. Thermal control is achieved by a combination of radiators, surface coatings, insulation, and heaters.

MRO's science payload includes the High Resolution Imaging Science Experiment (HiRISE), a visible stereo imaging camera; the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), a visible/near-infrared spectrometer to study the surface composition; the Mars Climate Sounder (MCS), an infrared radiometer to study the atmosphere, a shallow subsurface sounding radar (SHARAD) provided by the Italian Space Agency to search for underground water; the Context Camera (CTX), to provide wide-area views; and the Mars Color Imager (MARCI), to monitor clouds and dust storms. In addition, there are three engineering instruments aboard MRO: the Electra UHF communications and navigation package, used as a relay between the Earth and other Mars missions; the optical navigation camera, tested for possible navigational use on future planetary spacecraft; and the Ka-band telecommunications experiment package, for testing high performance Ka-band communications. Engineering accelerometer data is used to study the structure of the Martian atmosphere, and tracking of the orbiter is used to study the gravity field of Mars.

MRO HiRISE image of Phoenix lander descending at Mars, NASA/JPL photo
Source: Wikipedia

2008 20:38:00 PDT (GMT -7:00:00)
NASA's Phoenix lander touched down on Mars in the north polar region for a nominal 90 day mission.

NASA's Phoenix lander, launched 4 August 2007, was a robotic spacecraft on a space exploration mission to Mars under the Mars Scout Program. The Phoenix lander descended to the surface of Mars on 25 May 2008. Mission scientists used instruments aboard the lander to search for environments suitable for microbial life on Mars, and to research the history of water there.

Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (HiRISE) camera photographed Phoenix suspended from its parachute during its descent through the Martian atmosphere on 25 May 2008, the first time one spacecraft photographed another in the act of landing on a planet. Phoenix landed on Mars at 4:38 PM (PDT) at 68.218830 deg N 234.250778 deg E, NASA's sixth successful landing on Mars out of seven attempts, and was the first successful landing in a Martian polar region.

The lander completed its mission in August 2008, and made a last brief communication with Earth on 2 November 2008 as available solar power dropped with the Martian winter. The mission was declared concluded on 10 November 2008 after engineers were unable to re-contact the craft. Following unsuccessful attempts to contact the lander using the Mars Odyssey orbiter up to and past the Martian summer solstice on 12 May 2010, JPL declared the lander to be dead.

The program was considered a success because it completed all planned science experiments and observations.

See also the Wikipedia "Phoenix (spacecraft)" page

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