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Space History for October 24
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Race To Space
Someone will win the prize...
... but at what cost?
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1601
Died, Tycho Brahe, astronomer, in Prague at age 54
Tycho Brahe (14 December 1546 - 24 October 1601) was a Danish nobleman, well known as an astronomer/astrologer (the two were not yet distinct) and alchemist. He had Uraniborg built, which became an early "research institute." For purposes of publication, Tycho owned a printing press and paper mill.
Tycho realized that progress in the science of astronomy could be achieved not by occasional haphazard observations, but only by systematic and rigorous observation, night after night, and by using instruments of the highest accuracy obtainable. He is quoted as having asserted in 1563, at age 17, "I've studied all available charts of the planets and stars and none of them match the others. There are just as many measurements and methods as there are astronomers and all of them disagree. What's needed is a long term project with the aim of mapping the heavens conducted from a single location over a period of several years." He was able to improve and enlarge the existing instruments, and construct entirely new ones. Brahe's naked eye measurements of planetary parallax were accurate to the arcminute. (These measurements became the possessions of Johannes Kepler following Brahe's death.)
On 6 November 1572, Tycho had observed a very bright star which had unexpectedly appeared in the constellation Cassiopeia. Since it had been maintained since antiquity that the world of the fixed stars was eternal and unchangeable, other observers held that the phenomenon was something in the Earth's atmosphere. Tycho, however, observed that the parallax of the object did not change from night to night, suggesting that the object was far away. Tycho argued that a nearby object should appear to shift its position with respect to the background. He published a small book, De Stella Nova (1573), thereby coining the term nova for a "new" star. (We now know that Tycho's star was a supernova.)
King Frederick II of Denmark and Norway, impressed with Tycho's 1572 observations, financed the construction of two observatories for Tycho on the island of Hven in the Sont near Copenhagen, Uraniborg and Stjerneborg. Uraniborg also had a laboratory for Brahe's alchemical experiments. After a disagreement with Christian IV, the new king of Denmark, Brahe moved to Prague in 1599. Sponsored by Rudolf II, the Holy Roman Emperor, he built a new observatory (in a castle in Benatky nad Jizerou 50 km away from Prague) and worked there until his death.
http://galileo.rice.edu/sci/brahe.html
1632
Born, Antony van Leeuwenhoek, Dutch microscope pioneer, considered to be "the father of microbiology"
https://en.wikipedia.org/wiki/Antonie_van_Leeuwenhoek
1851
William Lassell discovered Ariel and Umbriel, satellites of Uranus.
https://en.wikipedia.org/wiki/William_Lassell
1861
The first transcontinental telegraph message across the US was sent by Justice Stephen J. Field in San Francisco, California to President Abraham Lincoln in Washington, DC. This event effectively put the Pony Express out of business.
https://www.loc.gov/item/today-in-history/october-24
1908
Born, Aleksei Mikhailovich Isayev, Russian engineer (rocket engines)
https://en.wikipedia.org/wiki/Aleksei_Isaev_%28engineer%29
1922
O. Struve discovered asteroid #991 McDonalda.
1960 15:45:00 GMT
A disaster on a Baikonur launch pad killed USSR missile expert Nedelin and the team working on the R-16 ICBM. 112 died, either at the scene, or from injuries. The USSR claimed they were killed in a plane crash.
The first attempted launch of the USSR R-16 ICBM on 24 October 1960 resulted in an explosion on the pad, killing over 100 military personnel, engineers and technicians. The first R-16 prototype was fueled and on the pad, awaiting launch. An electrical problem developed, leading to a hold in the countdown. Marshal Nedelin, commander of the Strategic Rocket Forces, ordered the engineers and technicians to fix the problem without the long delay of defueling and refurbishing the missile. He personally had a deck chair brought out to the pad so he could watch the work first-hand. At 18:45 local time (15:45 GMT), a spurious radio signal triggered ignition of the second stage while workers swarmed around the missile in its gantry. The missile exploded, killing a good part of the Soviet Union's rocket engineering and management talent. Among the dead were Nedelin, Konoptev, Grishin, Nosov, Kontsevsky, and Lev Berlin. 74 people were killed immediately, and 48 died in the ensuing weeks from burns or contact with the toxic and corrosive propellants. The total included 38 civilian engineers and 84 officers and enlisted rocket technicians. Yangel, the rocket's designer, was spared only because he had slipped into a bunker for a cigarette before the explosion occurred.
https://en.wikipedia.org/wiki/Nedelin_catastrophe
1961
A small liquid-fuel rocket was fueled and fired while floating in the ocean off Point Mugu in an Aerojet-General demonstration of the launching technique.
https://www.hq.nasa.gov/office/pao/History/Timeline/1961-4.html
1961
The USAF fired a Titan 1 Mark 4 from Cape Canaveral, Florida, to coincide with Midas IV passing overhead. The satellite successfully detected the launch, before one solar panel failed and its batteries ran down, ending its mission after just one week.
https://en.wikipedia.org/wiki/Missile_Defense_Alarm_System#Program_summary_and_launch_history
1962 17:55:04 GMT
USSR launched Sputnik 22 (Mars 1962A, Korabl 11) from Baiknour, a Mars probe intended to photograph Mars on a flyby trajectory which instead broke into pieces before achieving Earth orbit.
USSR launched Sputnik 22 on 24 October 1962, a Mars probe intended to photograph Mars on a flyby trajectory, presumably similar to the Mars 1 mission launched 8 days later. The intended Mars probe had a mass of 893.5 kg. The spacecraft and attached upper stage, with a total mass of 6500 kg, were launched by an SL-6 toward a 180 x 485 km Earth parking orbit with an inclination of 64.9 degrees. 16 seconds after ignition of Stage 4, the Block L's S1.5400A1 engine exploded because of a lubricant leak which resulted in jamming of a shaft in the turbopump gearbox, and break up of the turbine. The spacecraft broke into many pieces, some of which apparently remained in Earth orbit for a few days. This occurred during the Cuban missile crisis and was picked up by the US Ballistic Missile Early Warning System radar in Alaska, and was momentarily feared to be the start of a Soviet nuclear ICBM attack.
This spacecraft was originally designated Sputnik 29 in the US Naval Space Command Satellite Situation Summary.
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1962-057A
1965
Purple Mountain Observatory discovered asteroid #2398 Jilin.
1970
USSR's Zond 8 flew past the Moon at a distance of 690 mi (1110 km) and obtained both black and white and color photographs of the Lunar surface during the USSR's final circumlunar flight.
The USSR's final circumlunar flight, Zond 8 was launched 20 October 1970 from an Earth orbiting platform, Tyazheliy Sputnik (70-088B), towards the Moon for further demonstration of circumlunar flight, Lunar and planetary photography. The announced objectives were investigations of the Moon and circumlunar space, and testing of onboard systems and units.
The spacecraft obtained photographs of the Earth on 21 October from a distance of 64,480 km, and transmitted flight images of the Earth for three days. Zond 8 flew past the Moon on 24 October 1970 at a distance of 690 miles (1110 km), and obtained both black and white and color photographs of the Lunar surface. Scientific measurements were also obtained during the flight.
Zond 8 reentered the Earth's atmosphere and splashed down in the Indian Ocean on 27 October 1970. The spacecraft used a new variant of the double-dip re-entry, coming in over the North Pole, bouncing off the atmosphere, tracked by Soviet radar stations as it soared south over the Soviet Union, then making a final precision re-entry followed by splashdown at the recovery point in the Indian Ocean, the Soviets' second water recovery.
Zond 8 was recovered only 15 minutes after splashdown by the vessel Taman. Of five Zonds recovered, this was the only one to fly over the North Pole, the remainder re-entered over the South Pole. The reason for the different trajectory was the need to fly over tracking stations on Soviet territory in order to get trajectory updates that allowed a precise landing after the second plunge into the atmosphere. Mishin subsequently wanted a water landing for the L3, the dilemma being that after a first dip into the atmosphere over the North Pole, tracking for a precision landing is possible, but then the spacecraft cannot land on Soviet territory. Re-entering first over the South Pole would mean that no trajectory updates were available, but the spacecraft could land only imprecisely somewhere on Soviet territory.
15 L1's were completed, of which only five ever returned to Earth. Following this successful final recovery, the program was cancelled. The main cause of the project's failure was the unreliability of the UR-500K rocket.
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1970-088A
1976
R. M. West discovered asteroids #2052 Tamriko, #2053 Nuki, #2115 Irakli, #2935, #2116 Mtskheta, #2145 Blaauw, #2146 Stentor, #2148 Epeios, and #2187 La Silla.
1981
Purple Mountain Observatory discovered asteroids #3088 and #3462.
1984
Intelsat 5 F-9 re-entered Earth's atmosphere after the launch vehicle failed to place the satellite into a useful orbit on 9 June 1984.
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/displayTrajectory.action?id=1984-057A
1991
Died (cardiac arrest, age 70), Gene Roddenberry, creator of the Star Trek television series
https://en.wikipedia.org/wiki/Gene_Roddenberry
1995
A total solar eclipse occurred, visible over Southern Asia and the western Pacific, the totality lasting 2 minutes 9 seconds.
https://en.wikipedia.org/wiki/Solar_eclipse_of_October_24,_1995
1998 12:08:00 GMT
NASA launched the Deep Space 1 comet/asteroid mission satellite to asteroid 9969 Braille and comet Borrelly.
NASA's Deep Space 1 (DS1), launched 24 October 1998, was the first of a series of technology demonstration probes being developed by NASA's New Millennium Program. The spacecraft flew by the Mars-crossing near-Earth asteroid 9969 Braille (formerly known as 1992 KD) in July, 1999 and flew by comet Borrelly on 22 September 2001. As part of the technology demonstrations, the probe carried the Miniature Integrated Camera-Spectrometer (MICAS), an instrument combining two visible imaging channels with UV and IR spectrometers. MICAS was used to study the chemical composition, geomorphology, size, spin-state, and atmosphere of the target objects. It also carried the Plasma Experiment for Planetary Exploration (PEPE), an ion and electron spectrometer which measured the solar wind during cruise, the interaction of the solar wind with target bodies during encounters, and the composition of the cometary coma.
DS1 flew by the near-Earth asteroid 9969 Braille at 04:46 UT (12:46 a.m. EDT) on 29 July 1999 at a distance of about 26 km and at approximately 15.5 km/sec relative velocity. The spacecraft made its final pre-encounter transmission about 7 hours before closest approach, after which it turned its high-gain antenna away from Earth to point the MICAS camera/spectrometer camera towards the asteroid. The spacecraft had a target-tracking problem and the MICAS instrument was not pointed towards the asteroid as it approached, so no images or spectra were obtained. MICAS turned off about 25 seconds before closest approach at a distance of about 350 km and measurements were taken with the PEPE plasma instrument. The spacecraft then turned after the encounter to obtain images and spectra of the opposite side of the asteroid as it receded from view, but due to the target-tracking problem only two black and white images and a dozen spectra were obtained. The images were taken at 915 and 932 seconds after closest approach from 14,000 km and the spectra were taken about 3 minutes later. The data were transmitted back to Earth over the next few days. The diameter of Braille is estimated at 2.2 km at its longest and 1 km at its shortest. The spectra showed it to be similar to the asteroid Vesta.
The original plan was to fly by the dormant comet Wilson-Harrington in January 2001 and comet Borrelly in September 2001. The star tracker failed on 11 November 1999 and a new extended mission to fly by comet Borrelly (using techniques developed to operate the spacecraft without the star tracker) was planned. On 22 September 2001, Deep Space 1 entered the coma of comet Borrelly and made its closest approach (2171 km) to the nucleus at 22:29:33 UT (6:29:33 p.m. EDT) at a relative velocity of 16.58 km/second. At the time of the flyby the spacecraft and comet were 1.36 AU from the Sun. The PEPE instrument was turned on throughout the encounter. MICAS started making measurements and imaging 80 minutes before encounter and operated until a few minutes before encounter as planned. Both instruments successfully returned data and images from the encounter.
The ion engines on DS1 were commanded off on 18 December 2001 at about 20:00 UT (3:00 p.m. EST) to end the mission. The radio receiver was left on in case future contact with the spacecraft is desired. All new technologies on board DS1 were successfully tested during the primary mission.
Deep Space 1 comet probe, NASA illustration
Source: NSSDCA Master Catalog
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1998-061A
2000 16:00:00 CDT (GMT -5:00:00)
NASA's STS 92 (Discovery 28, Shuttle 100) ended, returning from the International Space Station Flight 3A mission.
STS 92 was launched 11 October 2000. It docked at the International Space Station on 13 October, and undocked prior to returning to Earth, on 20 October.
During STS 92, the crew brought the Z-1 Truss (mounted on a Spacelab pallet), Control Moment Gyros, Pressurized Mating Adapter-3 (PMA-3) and two DDCU (Heat pipes) to the International Space Station.
STS 92 crew members conducted four space walks on the outside of the docked complex. Beginning 15 October, space walkers conducted the complex, demanding tasks that were required for installation of the Z1 Truss and Pressurized Mating Adapter 3 onto the station's Unity module. Mission Specialists Leroy Chiao and Bill McArthur performed the first and third excursions. Mission Specialists Jeff Wisoff and Michael Lopez-Alegria performed the second and fourth. The total space walk time for the mission was 27 hours, 19 minutes.
During the International Space Station 3A mission (STS 92), the following elements were added: 1) Integrated Truss Structure Z1, an early exterior framework to allow the first US solar arrays on Flight 4A to be temporarily installed on Unity for early power; 2) Ku-band Communication System, to support early science capability and US television broadcasts on Flight 6A; 3) Control Moment Gyros, to provide non-propulsive (electrically powered) attitude control when activated on Flight 5A; and, 4) Pressurized Mating Adapter 3, to provide a shuttle docking port for solar array installation on Flight 4A, and Lab installation on Flight 5A.
STS 92 ended 24 October 2000 when Discovery landed at Edwards Air Force Base, California. Orbit altitude: 177 nautical miles. Orbit inclination: 51.6 degrees. Mission duration: 12 days, 21 hours, 43 minutes. Miles traveled: 5.3 million.
The flight crew for STS 92 was: Commander Brian Duffy, Pilot Pam Melroy, Mission Specialists Leroy Chiao, Bill McArthur, Koichi Wakata (NASDA), Jeff Wisoff and Mike Lopez-Alegria.
https://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-92.html
2001 02:26:00 GMT
NASA's 2001 Mars Odyssey arrived at Mars and went into orbit.
NASA's 2001 Mars Odyssey is the remaining part of the Mars Surveyor 2001 Project, which originally consisted of two separately launched missions, The Mars Surveyor 2001 Orbiter and the Mars Surveyor 2001 Lander. The lander spacecraft was cancelled as part of the reorganization of the Mars Exploration Program at NASA. The orbiter, renamed the 2001 Mars Odyssey, was nominally planned to orbit Mars for three years with the objective of conducting a detailed mineralogical analysis of the planet's surface from orbit and measuring the radiation environment. The mission had as its primary science goals to gather data to help determine whether the environment on Mars was ever conducive to life, to characterize the climate and geology of Mars, and to study potential radiation hazards to possible future astronaut missions. The orbiter also acted (and is acting, as of 2022) as a communications relay for [future] missions to Mars. It has enough propellant to function until 2025.
The 2001 Mars Odyssey was launched aboard a Delta II 7425 on 7 April 2001. In August, during the cruise to Mars, the MARIE instrument failed to respond during a routine data transfer and was put into hibernation. (Attempts to revive the instrument were successful in March 2002, and MARIE began taking scientific data from orbit on 13 March 2002.) After a seven month cruise the spacecraft reached Mars on 24 October 2001. The spacecraft used a 19.7 minute propulsive maneuver to transfer into an 18.6 hour elliptical capture orbit and used aerobraking until 11 January 2002, when the spacecraft pulled out of the aerobraking orbit into a 201 x 500 km orbit. This orbit was trimmed over the next few weeks until it became a 2-hour, approximately 400 x 400 km polar science orbit on 30 January 2002. The science mapping mission began on 19 February 2002, and on 28 May 2002, NASA reported that Odyssey's GRS had detected large amounts of hydrogen, a sign that there must be ice lying within a meter of the planet's surface. The Orbiter acts as a communications relay for the Mars Exploration Rovers (Spirit and Opportunity) which arrived in January 2004, the Mars Science Laboratory rover Curiosity, and will possibly also do so for other future missions. Data was collected from orbit until the end of the 917 day nominal mission in July 2004, and the mission was first extended for another Martian year, until September 2006.
One of the orbiter's three flywheels failed in June 2012. However, Odyssey's design included a fourth flywheel, a spare carried against exactly this eventuality. The spare was spun up and successfully brought into service. Since July 2012, Odyssey has been back in full, nominal operation mode following three weeks of 'safe' mode on remote maintenance.
On 11 February 2014, mission control accelerated Odyssey's drift toward a morning-daylight orbit to "enable observation of changing ground temperatures after sunrise and after sunset in thousands of places on Mars". The desired change occurred gradually until the intended orbit geometry was reached on 12 November 2015 when another maneuver was conducted to halt the drift. The new observations could yield insight about the composition of the ground and about temperature-driven processes, such as warm-season flows observed on some slopes, Martian morning clouds seen by the Viking Orbiter 1 in 1976, and geysers fed by spring thawing of carbon dioxide (CO2) ice near Mars' poles.
The 2001 Mars Odyssey carries star cameras, the Mars Radiation Environment Experiment (MARIE), which measures the near-space radiation environment as related to the radiation-related risk to human explorers, the Thermal Emission Imaging System (THEMIS), which maps the mineralogy of the Martian surface using a high-resolution camera and a thermal infrared imaging spectrometer, and the Gamma-Ray Spectrometer (GRS), which maps the elemental composition of the surface and determines the abundance of hydrogen in the shallow subsurface.
The main body of the 2001 Mars Odyssey is a box of 2.2 meters x 1.7 meters x 2.6 meters. The orbiter is divided into two modules, the upper equipment module and the lower propulsion module. The equipment module holds the equipment deck which supports the engineering components and the science instruments. Above the equipment module, connected by struts, is the science deck, holding the star cameras, high energy neutron detector, UHF antenna, the THEMIS instrument and a deployable 6 meter boom holding the gamma sensor head for the GRS. A set of solar array panels extends out from one side of the main bus. A parabolic high-gain dish antenna is mounted on a mast extending from one corner of the bottom of the bus. The MARIE instrument is mounted inside the spacecraft. In the propulsion module are the fuel, oxidizer and helium pressurization tanks, and the main engine. The main engine is a hydrazine and nitrogen tetroxide rocket which can produce 65.3 kg thrust, mounted in the bottom part of the propulsion module. The spacecraft had a launch mass of 725.0 kg, including 348.7 kg of fuel.
Attitude control is provided by four 0.1 kg thrusters and the spacecraft can be turned using four 2.3 kg thrusters. The spacecraft is three-axis stabilized using three primary reaction wheels and one backup. Navigation is provided by a Sun sensor, a star camera, and an inertial measurement unit. Power is provided by the gallium arsenide solar cells in the solar panel and a 16 amp-hr nickel hydrogen battery. Communications between the orbiter and Earth are in X-band via the high-gain antenna, and communications between the orbiter and any Mars landers are via the UHF antenna. Thermal control is achieved using a system of heaters, radiators, louvers, insulating blankets and thermal paint. Command and data handling is through a RAD6000 computer with 128 Mbytes RAM and 3 Mbytes of non-volatile memory.
See also the NASA/JPL 2001 Mars Odyssey Home Page
Artist's concept of 2001 Mars Odyssey in orbit over Mars, NASA illustration
Source: NSSDCA Master Catalog
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2001-013A
2003
The British/French Concorde SST made its last commercial flight, bringing its era of supersonic airliner transportation to a close.
http://news.bbc.co.uk/onthisday/hi/dates/stories/october/24/newsid_3701000/3701490.stm
2006 00:00:00 GMT
NASA's MESSENGER made its second planetary flyby on its way to Mercury orbit, passing Venus at an altitude of 2990 km.
The Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER) mission was designed to study the characteristics and environment of Mercury from orbit. Specifically, the scientific objectives of the mission were to characterize the chemical composition of Mercury's surface, the geologic history, the nature of the magnetic field, the size and state of the core, the volatile inventory at the poles, and the nature of Mercury's exosphere and magnetosphere over a nominal orbital mission of one Earth year.
MESSENGER launched into a parking orbit on 3 August 2004 on a Delta 7925H (a Delta II Heavy launch vehicle with nine strap-on solid-rocket boosters). The Delta booster second stage's second burn raised the orbit, then the PAM-D solid motor burned to put the probe on an escape trajectory into a 0.92 x 1.08 AU x 6.4 deg heliocentric orbit. The spacecraft was injected into solar orbit 57 minutes after launch. The solar panels were then deployed and the spacecraft began sending data on its status.
One year after launch, on 2 August 2005, MESSENGER flew by Earth at an altitude of 2347 km. On 12 December 2005 at 11:30 UT, MESSENGER fired its large thruster for 524 seconds, changing the spacecraft velocity by 316 m/s and putting it on course for its 24 October 2006 Venus flyby at an altitude of 2990 km. The second Venus flyby took place on 5 June 2007 at 23:08 UT (7:08 p.m. EDT) at an altitude of approximately 337 km. The first of three Mercury flybys, all at roughly 200 km altitude, occurred on 14 January 2008 at 19:04 :39 UT, and the second on 6 October 2008 at 08:40:22 UT. The third took place on 29 September 2009 at 21:54:58 UT at a distance of 228 km. There were also five deep space manuevers. Data collected during the Mercury flybys was used to help plan the scientific campaign during the orbital phase.
Mercury orbit insertion took place with a 15 minute burn starting at 00:45 UT on 18 March 2011 (8:45 p.m. 17 March EDT) requiring a delta-V of 0.862 km/s from the Aerojet 660N engine. Science observations began on April 4 at 20:40 UT (4:40 p.m. EDT). The nominal orbit had a periapsis of 200 km at 60 degrees N latitude, an apoapsis of 15,193 km, a period of 12 hours and an inclination of 80 degrees. The periapsis slowly rose due to solar perturbations to over 400 km at the end of 88 days (one Mercury year) at which point it was readjusted to a 200 km, 12 hour orbit via a two burn sequence.
Data was collected from orbit for one Earth year, the end of the primary mission was in March 2012. Extensions to the mission allowed the spacecraft to operate for an additional 3 years until the propellant necessary to maintain its orbit was exhausted. The MESSENGER spacecraft impacted the surface of Mercury as planned on 30 April 2015 at 19:26 UT (3:26 p.m. EDT).
Global stereo image coverage at 250 m/pixel resolution was completed. The mission has also yielded global composition maps, a 3-D model of Mercury's magnetosphere, topographic profiles of the northern hemisphere, gravity field, altitude profiles of elemental species, and a characterization of the volatiles in permanently shadowed craters at the poles.
The MESSENGER spacecraft was a squat box (1.27 m x 1.42 m x 1.85 m) with a semi-cylindrical thermal shade (roughly 2.5 meters tall and 2 meters wide) for protection from the Sun and two solar panel wings extending radially about 6 meters from tip to tip. A 3.6 meter magnetometer boom also extended from the craft. The total mass of the spacecraft was 1093 kg, 607.8 kg of which was propellant and helium. The structure was primarily graphite-cyanate-ester (GrCE) composite and consisted of two vertical panels which supported two large fuel tanks, and two vertical panels which supported the oxidizer tank and plumbing panel. The four vertical panels made up the center column and were bolted at their aft ends to an aluminum adapter. A single top deck panel mounted the LVA (large velocity adjust) thruster, small thrusters, helium and auxiliary fuel tanks, star trackers and battery.
Main propulsion was via the 645-N, 317-s bipropellant LVA thruster, four 22-N monopropellant thrusters providing spacecraft steering during main thruster burns, and ten 4-N monopropellant thrusters used for attitude control. There was also a reaction-wheel attitude control system. Knowledge for attitude control was provided by star tracking cameras, an inertial measurement unit, and six solar sensors. Power was provided by the solar panels, which extended beyond the sunshade and were rotatable to balance panel temperature and power generation, and provided a nominal 450 W in Mercury orbit. The panels were 70% optical solar reflectors and 30% GaAs/Ge cells. The power was stored in a common-pressure-vessel nickel-hydrogen battery, with 11 vessels and 2 cells per vessel.
Communications were in the X-band, with downlink through two fixed phased-array antenna clusters, and uplink and downlink through medium- and low-gain antennas on the forward and aft sides of the spacecraft. Passive thermal control, primarily a fixed opaque ceramic cloth sunshade, was utilized to maintain operating temperatures near the Sun. Radiators were built into the structure and the orbit was optimized to minimize infrared and visible light heating of the spacecraft from the surface of Mercury. Multilayer insulation, low conductivity couplings, and heaters were also used to maintain temperatures within operating limits.
Five science instruments were mounted externally on the bottom deck of the main body: the Mercury Dual Imaging System (MDIS), Gamma-Ray and Neutron Spectrometer (GRNS), X-ray Spectrometer (XRS), Mercury Laser Altimeter (MLA), and Atmospheric and Surface Composition Spectrometer (MASCS). The Energetic Particle and Plasma Spectrometer (EPPS) was mounted on the side and top deck and the magnetometer (MAG) was at the end of the 3.6 m boom. Radio Science (RS) experiments used the existing communications system.
The highly successful orbital mission came to an end after more than four years in orbit around Mercury, as the spacecraft ran out of propellant and the force of solar gravity caused it to impact the surface of Mercury at 3:26 p.m. EDT on 30 April 2015.
More information about the spacecraft and its research results can be found on the MESSENGER Web site at John Hopkins University's Applied Physics Laboratory.
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2004-030A
2014
Alan Eustace, an American computer scientist, made a parachute jump from the stratosphere from a record 135,889.108 feet (41.419000 km; 25.7365735 mi) with a peak speed over 821.45 miles per hour (1,322.00 km/h).
The suit worn by Alan Eustace during his record setting jump, on display at the Udvar-Hazy Center in Dulles, Virginia
Source: Wikipedia
https://en.wikipedia.org/wiki/Alan_Eustace#Stratosphere_jump
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