Mariner 9 (Mariner Mars '71 / Mariner-I) was a robotic space probe that contributed greatly to the exploration of Mars and was part of the NASA Mariner program. Mariner 9 was launched toward Mars on May 30, 1971 from LC-36B at Cape Canaveral Air Force Station, Florida, and reached the planet on November 14 of the same year, becoming the first spacecraft to orbit another planet – only narrowly beating the Soviet probes "Mars 2" (launched May 19) and "Mars 3" (launched May 28), which both arrived at Mars only weeks later. After the occurrence of dust storms on the planet for several months following its arrival, the orbiter managed to send back clear pictures of the surface.
Introduction
Mariner 9
Mariner 9 | Introduction
It was a robotic space probe It was a robotic space probe. Yes. No, it is a very large shield volcano on the planet Mars.
what is the location of mars in the solar system
user
Mars is the fourth planet from the Sun
assistant
is it known by any other names?
user
Yes, "Red Planet" in English
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are there any volcanoes there?
user
Yes, Olympus Mons
assistant
who named it?
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Named after observations made by Mariner 9
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what was that?
user
From Nix Olympica; a volcano. Astronomers adopted the name "Olympus Mons" for the albedo feature known as Nix Olympica
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was that a spaceship that made the observations?
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Observations of the planet from Mariner 9 confirmed that Nix Olympica was a volcano. Ultimately, astronomers adopted the name "Olympus Mons" for the albedo feature known as Nix Olympica.
Olympus Mons | Early observations and naming
Olympus Mons and a few other volcanoes in the Tharsis region stand high enough to reach above the frequent Martian dust-storms recorded by telescopic observers as early as the 19th century. The astronomer Patrick Moore pointed out that Schiaparelli (1835–1910) "had found that his "Nodus Gordis" and "Olympic Snow" [Nix Olympica] were almost the only features to be seen" during dust storms, and "guessed correctly that they must be high". The Mariner 9 spacecraft arrived in orbit around Mars in 1971 during a global dust-storm. The first objects to become visible as the dust began to settle, the tops of the Tharsis volcanoes, demonstrated that the altitude of these features greatly exceeded that of any mountain found on Earth, as astronomers expected.
Olympus Mons | Early observations and naming
After 349 days in orbit, Mariner 9 had transmitted 7,329 images, covering 85% of Mars' surface, whereas previous flyby missions had returned less than one thousand images covering only a small portion of the planetary surface. The images revealed river beds, craters, massive extinct volcanoes (such as Olympus Mons, the largest known volcano in the Solar System; Mariner 9 led directly to its reclassification from Nix Olympica), canyons (including the Valles Marineris, a system of canyons over about long), evidence of wind and water erosion and deposition, weather fronts, fogs, and more. Mars' small moons, Phobos and Deimos, were also photographed.
Mariner 9 | Achievements
These pictures were the first to offer more detailed evidence that liquid water might at one time have flowed on the planetary surface. They also finally discerned the true nature of many Martian albedo features. For example, Nix Olympica was one of only a few features that could be seen during the planetary duststorm, revealing it to be the highest mountain (volcano, to be exact) on any planet in the entire Solar System, and leading to its reclassification as Olympus Mons.
Exploration of Mars | Mariner program
By chance, both spacecrafts flew over cratered regions and missed both the giant northern volcanoes and the equatorial grand canyon discovered later. Their approach pictures did, however, photograph about 20 percent of the planet's surface, showing the dark features long seen from Earth – in the past, these features had been mistaken for canals by some ground-based astronomers. When Mariner 7 flew over the martian south pole on August 4, 1969, it sent back pictures of ice-filled craters and outlines of the south polar cap. Despite the communication defect suffered by Mariner 7 earlier, these pictures were of better quality than what had been sent by its twin, Mariner 6, a few days earlier when it flew past the martian equator.
Mariner 6 and 7 | Science data and findings
The main surface imaging did not get underway until mid-January 1972. However, surface-obscured images did contribute to the collection of Mars science, including understanding of the existence of several huge high-altitude volcanoes of the Tharsis Bulge that gradually became visible as the dust storm abated. This unexpected situation made a strong case for the desirability of studying a planet from orbit rather than merely flying past. It also highlighted the importance of flexible mission software. The Soviet Union's Mars 2 and Mars 3 probes, which arrived during the same dust storm, were unable to adapt to the unexpected conditions, which severely limited the amount of data that they were able to collect.
Mariner 9 | Achievements
One famous Mars realization was that what was then called "Nix Olympica" was a volcano, and then renamed Olympus Mons thanks to Mariner 9 orbiter observations in the early 1970s. Endeavour was identified as having clay minerals, as detected from orbit by Mars Reconnaissance Orbiter, which according to theories at that time indicated rock from an older, wetter, time period on Mars. This type of rock is different from what prevails in other areas of surrounding plains. What is expected to be a fluid-carved gully was identified at Endeavour, probably water. This gully is targeted for exploration by the MER-B rover mission as of October 2016.
Endeavour (crater) | Geology
The volcano's location corresponds to the classical albedo feature Ascraeus Lacus. Ascraeus Mons was discovered by the Mariner 9 spacecraft in 1971. The volcano was originally called North Spot because it was the northernmost of only four spots visible on the surface due to a global dust storm that was then enshrouding the planet. As the dust cleared, the spots were revealed to be extremely tall volcanoes whose summits had projected above the dust-laden, lower atmosphere.
Ascraeus Mons | Discovery
The 8.4 μm channel also showed a slight phase effect. The phase effect indicated that if a greenhouse effect existed, heat was transported in an efficient manner from the light side to the dark side of the planet. The 8.4 μm and 10.4 μm showed equal radiation temperatures, indicating that the limb darkening effect would appear to come from a cloud structure rather than the atmosphere. Thus, if the measured temperatures were actually cloud temperatures instead of surface temperatures, then these clouds would have to be quite thick. The magnetometer detected a persistent interplanetary magnetic field varying between 2 γ and 10 γ (nanotesla), which agrees with prior Pioneer 5 observations from 1960.
Mariner 2 | Scientific observations
The curvature of the planet and the volcano itself would obscure such a synoptic view. Similarly, an observer near the summit would be unaware of standing on a very high mountain, as the slope of the volcano would extend far beyond the horizon, a mere 3 kilometers away.
Olympus Mons | Description
In total, 201 photos were taken and transmitted back to Earth, adding more detail than the earlier mission, Mariner 4. Both crafts also studied the atmosphere of Mars. Coming a week after Apollo 11, Mariner 6 and 7's flyby of Mars received less than the normal amount of media coverage for a mission of this significance. The ultraviolet spectrometer onboard Mariners 6 and 7 was constructed by University of Colorado's Laboratory for Atmospheric and Space Physics (LASP).
Mariner 6 and 7 | Science data and findings
The Mariner 6 and 7 spacecraft were identical, consisting of an octagonal magnesium frame base, diagonally and deep. A conical superstructure mounted on top of the frame held the high-gain 1 meter diameter parabolic antenna and four solar panels, each measuring 215 x , were affixed to the top corners of the frame. The tip-to-tip span of the deployed solar panels was 5.79 m. A low-gain omnidirectional antenna was mounted on a 2.23 m high mast next to the high-gain antenna. Underneath the octagonal frame was a two-axis scan platform which held scientific instruments. Overall science instrument mass was .
Mariner 6 and 7 | Spacecraft and subsystems
It had been known to astronomers since the late 19th century as the albedo feature Nix Olympica (Latin for "Olympic Snow"). Its mountainous nature was suspected well before space probes confirmed its identity as a mountain. The volcano is located in Mars' western hemisphere at approximately , just off the northwestern edge of the Tharsis bulge. The western portion of the volcano lies in the Amazonis quadrangle (MC-8) and the central and eastern portions in the adjoining Tharsis quadrangle (MC-9). Two impact craters on Olympus Mons have been assigned provisional names by the International Astronomical Union. They are the -diameter Karzok crater () and the -diameter Pangboche crater ().
Olympus Mons | Introduction
This would cause a roll error transient as the object passed through the field-of-view while the sensor was locked onto Canopus. When the object was bright enough that it exceeded the high gate limits at eight times the Canopus intensity, the spacecraft would automatically disacquire Canopus and initiate a roll search for a new star. Finally, a radio command was sent on December 17, 1964, that removed the high gate limit. There was no further loss of Canopus lock, although roll transients occurred 38 more times before encounter with Mars.
Mariner 4 | Lock on Canopus
When the Mariner 9 probe arrived at Mars in 1971, scientists expected to see crisp new pictures of surface detail. Instead they saw a near planet-wide dust storm with only the giant volcano Olympus Mons showing above the haze. The storm lasted for a month, an occurrence scientists have since learned is quite common on Mars. Using data from Mariner 9, James B. Pollack et al. proposed a "mechanism for Mars dust storms" in 1973. As observed by the "Viking" spacecraft from the surface, "during a global dust storm the diurnal temperature range narrowed sharply, from 50°C to about 10°C, and the wind speeds picked up considerably—indeed, within only an hour of the storm's arrival they had increased to , with gusts up to .
Climate of Mars | Dust storms
The ultraviolet spectrometer aboard Mariner 9 was constructed by the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, Colorado. The ultraviolet spectrometer team was led by Professor Charles Barth. The Infrared Interferometer Spectrometer (IRIS) team was led by Dr. Rudolf A. Hanel from NASA Goddard Spaceflight Center (GSFC). The IRIS instrument was built by Texas Instruments, Dallas, Texas. The Infrared Radiometer (IRR) team was led by Professor Gerald Neugebauer from the California Institute of Technology (Caltech).
Mariner 9 | Construction
Using the plasma detectors, Mariner 10 gathered the first "in situ" solar wind data from inside Venus' orbit. Shortly after launch, scientists found that the Scanning Electrostatic Analyzer had failed because a door shielding the analyzer did not open. An unsuccessful attempt was made to forcibly unfasten the door with the first course correction maneuver. The experiment operators had planned to observe the directions taken by positive ions prior to the ions' collision with the Analyzer, but this data was lost. The experiment was still able to collect some data using the properly functioning Scanning Electron Spectrometer.
Mariner 10 | Plasma detectors
The first attempt at a midcourse maneuver was aborted by a loss of lock shortly after the gyros began spinup. Canopus lock was lost six times within a period of less than three weeks after launch and each time a sequence of radio commands would be required to reacquire the star. After a study of the problem, the investigators concluded that the behavior was due to small dust particles that were being released from the spacecraft by some means and were drifting through the star sensor field-of-view. Sunlight scattered from the particles then appeared as illumination equivalent to that from a bright star.
Mariner 4 | Lock on Canopus
NASA still held out hope that another Mariner probe and Atlas-Centaur could be readied before the 1971 Mars launch window closed. A few logistical problems emerged, including the lack of an available Centaur payload shroud of the correct configuration for the Mariner probes, however there was a shroud in NASA's inventory which could be modified. Convair also had an available Centaur stage on hand and could have an Atlas readied in time, but the idea was ultimately abandoned for lack of funding. Mariner 9 was mated to Atlas-Centaur AC-23 on May 9 with investigation into Mariner 8's failure ongoing. The malfunction was traced to a problem in the Centaur's pitch control servoamplifier and because it was not clear if the spacecraft itself had been responsible, RFI testing was conducted on Mariner 9 to ensure the probe was not releasing interference that could cause problems with the Centaur's electronics.
Mariner 9 | Objectives
In the "lower" , Bay 1 contained a motion chair that measured the mass of the crew; Bay 2, two performance test panels; Bay 3, the environmental control system controls; Bay 4, a physiology test console; Bay 5, an exercise device; Bay 6, two emergency oxygen masks; Bay 7, a view port and instrument panel; and Bay 8, the main spacecraft control station. From its regular orbit, the main Dorian camera had a circular field of view across. At top magnification it was more like . This was much smaller than many of the targets that the NRO was interested in, such as air bases, shipyards and missile ranges, so the astronauts would have limited time to respond as the MOL passed over them.
Manned Orbiting Laboratory | Laboratory module
The total data returned by the mission was 5.2 million bits (about 634 kB). All instruments operated successfully with the exception of a part of the ionization chamber, namely the Geiger–Müller tube, which failed in February 1965. In addition, the plasma probe had its performance degraded by a resistor failure on December 8, 1964, but experimenters were able to recalibrate the instrument and still interpret the data. The images returned showed a Moon-like cratered terrain, which scientists did not expect, although amateur astronomer Donald Cyr had predicted craters. Later missions showed that the craters were not typical for Mars, but only for the more ancient region imaged by Mariner 4.
Mariner 4 | Results
Mariner 9 was designed to continue the atmospheric studies begun by Mariner 6 and 7, and to map over 70% of the Martian surface from the lowest altitude () and at the highest resolutions (from 1 kilometer per pixel to 100 meters per pixel) of any Mars mission up to that point. An infrared radiometer was included to detect heat sources in search of evidence of volcanic activity. It was to study temporal changes in the Martian atmosphere and surface. Mars' two moons were also to be analyzed. Mariner 9 more than met its objectives. Under original plans, a dual mission was to be flown like Mariners 6–7, however the launch failure of Mariner 8 ruined this scheme and forced NASA planners to fall back on a simpler one-probe mission.
Mariner 9 | Objectives
Alba's size and low profile makes it a difficult structure to study visually, as much of the volcano's relief is indiscernible in orbital photographs. However, between 1997 and 2001, the Mars Orbital Laser Altimeter (MOLA) instrument of the Mars Global Surveyor spacecraft took over 670 million precise elevation measurements across the planet. Using MOLA data, planetary scientists are able to study subtle details of the volcano's shape and topography that were invisible in images from earlier spacecraft such as Viking. The volcano consists of two, roughly concentric components: 1) an oval-shaped central body with approximate dimensions of by across surrounded by 2) a vast, nearly level apron of lava flows that extends an additional or so outward.
Alba Mons | Physical description
Mariner 9 was the first spacecraft to orbit another planet. It carried an instrument payload similar to Mariners 6 and 7, but because of the need for a larger propulsion system to control the spacecraft in Martian orbit, it weighed more than Mariners 6 and 7 combined. When Mariner 9 arrived at Mars on November 14, 1971, planetary scientists were surprised to find the atmosphere was thick with "a planet-wide robe of dust, the largest storm ever observed." The surface was totally obscured. Mariner 9's computer was thus reprogrammed from Earth to delay imaging of the surface for a couple of months until the dust settled.
Mariner 9 | Achievements
The total height of the spacecraft was 3.35 m. The spacecraft was attitude stabilized in three axes, referenced to the sun and the star Canopus. It utilized 3 gyros, 2 sets of 6 nitrogen jets, which were mounted on the ends of the solar panels, a Canopus tracker, and two primary and four secondary sun sensors. Propulsion was provided by a 223-newton rocket motor, mounted within the frame, which used the mono-propellant hydrazine. The nozzle, with 4-jet vane vector control, protruded from one wall of the octagonal structure. Power was supplied by 17,472 photovoltaic cells, covering an area of on the four solar panels.
Mariner 6 and 7 | Spacecraft and subsystems
This experiment investigated the mass and gravitational characteristics of Mercury. It was of particular interest because of the planet's closeness to the Sun, large orbital eccentricity, and unusual spin-orbit resonance. As the spacecraft passed behind Mercury on the first encounter there was an opportunity to probe the atmosphere and to measure the radius of the planet. By observing phase changes in the S-band radio signal, measurements of the atmosphere could be made. The atmosphere was assessed as having a density of about .
Mariner 10 | Celestial Mechanics and Radio Science experiment
Mariner 9 (Mariner Mars '71 / Mariner-I) was a robotic space probe that contributed greatly to the exploration of Mars and was part of the NASA Mariner program. Mariner 9 was launched toward Mars on May 30, 1971 from LC-36B at Cape Canaveral Air Force Station, Florida, and reached the planet on November 14 of the same year, becoming the first spacecraft to orbit another planet – only narrowly beating the Soviet probes "Mars 2" (launched May 19) and "Mars 3" (launched May 28), which both arrived at Mars only weeks later. After the occurrence of dust storms on the planet for several months following its arrival, the orbiter managed to send back clear pictures of the surface.
Mariner 9 | Introduction
The probe continued photographing Venus until 13 February 1974. Among the encounter's 4165 acquired photographs, one resulting series of images captured a thick and distinctly patterned atmosphere making a full revolution every four days, just as terrestrial observations had suggested. The mission revealed the composition and meteorological nature of the atmosphere of Venus. Data from the radio science experiment measured the extent to which radio waves passing through the atmosphere were refracted, which was used to calculate the density, pressure, and temperature of the atmosphere at any given altitude. Overall, atmospheric temperature is higher closer to the planet's surface, but "Mariner 10" found four altitudes where the pattern was reversed, which could signify the presence of a layer of clouds.
Mariner 10 | Venus flyby
The Herschel telescope observed far-infrared emission spectra from Ceres indicating water loss. Though debatable at the time, the subsequent Dawn probe would use a different method (thermal neutrons) to detect subsurface hydrogen (in water or ammonium) at high Cererean latitudes, and a third method (near-infrared spectra) for likely local emissions. A fourth line of evidence, relaxation of large craters, suggests a mechanically weak subsurface such as frozen volatiles. The feature Ahuna Mons is most likely cryovolcanic: a Cererean pingo.
Asteroidal water | (1) Ceres
Data acquisition resumed in late 1967. The cosmic dust detector registered 17 hits in a 15-minute span on September 15, part of an apparent micrometeoroid shower that temporarily changed the spacecraft attitude and probably slightly damaged its thermal shield. Later it was speculated that Mariner 4 passed through debris of D/1895 Q1 (D/Swift), and even made a flyby of that comet's possibly shattered nucleus at 20 million kilometers. On December 7 the gas supply in the attitude control system was exhausted, and between December 10 and 11, a total of 83 micrometeoroid hits were recorded which caused perturbation of the spacecraft's attitude and degradation of the signal strength.
Mariner 4 | Micrometeoroid hits and end of communications
After Sun acquisition, the Canopus star tracker went searching for Canopus. The star tracker was set to respond to any object more than one-eighth as, and less than eight times as bright as Canopus. Including Canopus, there were seven such objects visible to the sensor. It took more than a day of "star-hopping" to find Canopus, as the sensor locked on to other stars instead: a stray light pattern from the near Earth, Alderamin, Regulus, Naos, and Gamma Velorum were acquired before Canopus. A consistent problem that plagued the spacecraft during the early portion of its mission was that roll error signal transients would occur frequently and on occasion would cause loss of the Canopus star lock.
Mariner 4 | Lock on Canopus
In 1980, Philippe Masson of the University of Paris-Sud offered an integrated interpretation of the structural geochronology of Valles Marineris, Noctis Labyrinthus, and Claritas Fossae in light of imagery from Mariner 9 and the Viking Orbiter. In 2003, Daniel Mège (Pierre and Marie Curie University), Anthony C. Cook (University of Nottingham and the Smithsonian Institution), Erwan Garel (University of Maine in France), Yves Lagabrielle (University of Western Brittany), and Marie-Hélène Cormier (Columbia University) proposed a model for rifting on Mars initiated by the deflation of magma chambers, forming pit crater chains tracking directionally with simple graben. The researchers offered the first theoretical explanation as to how the chasmata of Noctis Labyrinthus formed.
Noctis Labyrinthus | Observational history
The mountain was discovered on images taken by the "Dawn" spacecraft in orbit around Ceres in 2015. It is estimated to have an average height of about and a maximum height of about on its steepest side; it is about wide at the base.
Ahuna Mons | Discovery
Approximately 250 seconds after landing in the Oceanus Procellarum, four petals that covered the top half of the spacecraft opened outward for increased stability. The television camera system began a photographic survey of the lunar environment. Seven radio sessions with a total of 8 hours and 5 minutes were transmitted, as well as three series of TV pictures. After assembly the photographs gave a panoramic view of the immediate lunar surface, comprising views of nearby rocks and of the horizon, away. The pictures from "Luna 9" were not released immediately by the Soviet authorities, but scientists at Jodrell Bank Observatory in England, which was monitoring the craft, noticed that the signal format used was identical to the internationally agreed Radiofax system used by newspapers for transmitting pictures.
Luna 9 | Surface operations
The Radar System then recorded the brightness of each pulse as it reflected back off the side surfaces of rocks, cliffs, volcanoes and other geologic features, as a form of backscatter. To increase the imaging resolution, "Magellan" recorded a series of data bursts for a particular location during multiple instances called, "looks". Each "look" slightly overlapped the previous, returning slightly different information for the same location, as the spacecraft moved in orbit. After transmitting the data back to Earth, Doppler modeling was used to take the overlapping "looks" and combine them into a continuous, high resolution image of the surface.
Magellan (spacecraft) | Scientific instruments
Starting on December 3, the radiation around Jupiter caused false commands to be generated. Most of these were corrected by contingency commands, but an image of Io and a few close-ups of Jupiter were lost. Similar false commands would be generated on the way out from the planet. Nonetheless, "Pioneer 10" did succeed in obtaining images of the moons Ganymede and Europa. The image of Ganymede showed low albedo features in the center and near the south pole, while the north pole appeared brighter. Europa was too far away to obtain a detailed image, although some albedo features were apparent.
Pioneer 10 | Encounter with Jupiter
The final mission in the series, Mariner 10, flew past Venus before going on to encounter Mercury, after which it returned to Mercury for a total of three flybys. The next-to-last, Mariner 9, became the first ever to orbit another planet when it reached Mars for about a year of mapping and measurement. The Mariners were all relatively small robotic explorers, each launched on an Atlas rocket with either an Agena or Centaur upper-stage booster, and weighing less than half a ton (without onboard rocket propellant). Each of their missions was completed within a few months to a year or two, though one of them outlived its original mission and continued to send useful scientific data for three years.
Mariner program | Introduction
Mariner 9 team members named it the "Inca City". It looked like sand dunes that had formed from winds that blew from two different directions, but the dunes were too big. In 2002 the camera on Mars Global Surveyor revealed that the 'Inca City' was part of a large circular structure that was 86 km in diameter. So the shape meant that it was probably caused by an asteroid impact which cracked the crust. Later, magma flowed along the cracks. When the magma cooled, hard, erosion resistant walls of rock (dikes) formed. The crater was covered over, then partially exhumed.
Angustus Labyrinthus | Introduction
The Soviet probe "Venera 9" entered orbit on October 22, 1975, becoming the first artificial satellite of Venus. A battery of cameras and spectrometers returned information about the planet's clouds, ionosphere and magnetosphere, as well as performing bi-static radar measurements of the surface. The 660 kg (1,455 lb) descent vehicle separated from "Venera 9" and landed, taking the first pictures of the surface and analyzing the crust with a gamma ray spectrometer and a densitometer. During descent, pressure, temperature and photometric measurements were made, as well as backscattering and multi-angle scattering (nephelometer) measurements of cloud density. It was discovered that the clouds of Venus are formed in three distinct layers.
Observations and explorations of Venus | Venera 9 and 10
This included the appearance of a new lava flow, Zamama, and the shifting of the Prometheus plume by to the west, tracking the end of a new lava flow at Prometheus. Starting with "Galileo"'s first orbit, the spacecraft's camera, the Solid-State Imager (SSI), began taking one or two images per orbit of Io while the moon was in Jupiter's shadow. This allowed "Galileo" to monitor high-temperature volcanic activity on Io by observing thermal emission sources across its surface. The same eclipse images also allowed "Galileo" scientists to observe aurorae created by the interaction between Io's atmosphere and volcanic plumes with the Io flux tube and the plasma torus.
Exploration of Io | Galileo : era 1995–2003
was discovered on 10 December 2001 by David C. Jewitt, Scott S. Sheppard and Jan Kleyna using 2.2-meter University of Hawaii reflector on Mauna Kea. belongs to the dynamically cold population of the classical Kuiper belt objects, which small orbital eccentricities and inclinations. Their semi-major axes reside mainly in the interval 40–45 AU.
(524366) 2001 XR254 | Discovery and orbit
The microwave radiometer made three scans of Venus in 35 minutes on December 14, 1962 starting at 18:59 UTC. The first scan was made on the dark side, the second was near the terminator, and the third was located on the light side. The scans with the 19 mm band revealed peak temperatures of on the dark side, 595 ± 12 K near the terminator, and 511 ± 14 K on the light side. It was concluded that there is no significant difference in temperature across Venus. However, the results suggest a limb darkening, an effect which presents cooler temperatures near the edge of the planetary disk and higher temperatures near the center.
Mariner 2 | Scientific observations
On September 8 at 12:50 UTC, the spacecraft experienced a problem with attitude control. It automatically turned on the gyros, and the cruise science experiments were automatically turned off. The exact cause is unknown as attitude sensors went back to normal before telemetry measurements could be sampled, but it may have been an Earth-sensor malfunction or a collision with a small unidentified object which temporarily caused the spacecraft to lose Sun lock. A similar experience happened on September 29 at 14:34 UTC. Again, all sensors went back to normal before it could be determined which axis had lost lock. By this date, the Earth sensor brightness indication had essentially gone to zero.
Mariner 2 | Loss of attitude control
A penetrometer studied the composition of the surface as the craft impacted it, and it was initially reported that the surface was similar to wet clay, or perhaps crème brûlée (that is, a hard crust covering a sticky material). Subsequent analysis of the data suggests that this reading was likely caused by "Huygens" displacing a large pebble as it landed, and that the surface is better described as a "sand" made of ice grains. The images taken after the probe's landing show a flat plain covered in pebbles. The pebbles may be made of water ice and are somewhat rounded, which may indicate the action of fluids.
Lakes of Titan | Equatorial in-situ observations by the Huygens probe
Mariner 9 successfully entered orbit about Mars, the first spacecraft ever to do so, after the launch time failure of its sister ship, Mariner 8. When Mariner 9 reached Mars in 1971, it and two Soviet orbiters (Mars 2 and Mars 3, see "Mars probe program" above) found that a planet-wide dust storm was in progress. The mission controllers used the time spent waiting for the storm to clear to have the probe rendezvous with, and photograph, Phobos. When the storm cleared sufficiently for Mars' surface to be photographed by Mariner 9, the pictures returned represented a substantial advance over previous missions.
Exploration of Mars | Mariner program
This asteroid has been recorded at such observatories as:
1999 LE31 | Observations
In September 1994, photometric observations of "Ulysses" were made by astronomers Stefano Mottola and Uri Carsenty at ESO's La Silla Observatory, Chile, using the Bochum 0.61-metre Telescope. The observations were used to build a lightcurve showing a well-defined rotation period of 28.72 hours with a brightness variation of 0.32 magnitude (). In March 2014, another rotational lightcurve was obtained in the R-band by astronomers at the Palomar Transient Factory, California, which gave a concurring period of 28.7840 hours with an amplitude of 0.33 magnitude (). While not being a slow rotator, "Ulysses" period longer than the 2 to 20 hours measured for most asteroids.
5254 Ulysses | Photometry
NASA describes the spacecraft as: nearly identical to the Venera 1 design, a cylindrical body about 2 meters high with two solar panel wings, a 2.33 meter high-gain net antenna, and a long antenna arm, and had a mass of about 650 kg. It carried a 10 kg science payload consisting of a magnetometer on a boom, cosmic ray counter, plasma-ion trap, a radiometer, a micrometeorite detector, and a spectroreflectometer to study the CH band, a possible indicator of life on Mars. These instruments were mounted on the outside of the spacecraft. A photo-television camera was held in a sealed module in the spacecraft and could take pictures through a viewport when a sensor indicated the Sun-illuminated martian surface was in view.
Mars 1M | Spacecraft and subsystems
Mars has long been the subject of human interest. Early telescopic observations revealed color changes on the surface that were attributed to seasonal vegetation and apparent linear features were ascribed to intelligent design. Further telescopic observations found two moons, Phobos and Deimos, polar ice caps and the feature now known as Olympus Mons, the Solar System's second tallest mountain. The discoveries piqued further interest in the study and exploration of the red planet. Mars is a rocky planet, like Earth, that formed around the same time, yet with only half the diameter of Earth, and a far thinner atmosphere; it has a cold and desert-like surface.
Exploration of Mars | Martian system
The Mariner 6, Mariner 7, and Mariner 9 spacecraft carried thermal infrared radiometers, and a global map of thermal inertia was produced from modeled surface temperatures collected by the Infrared Thermal Mapper Instruments (IRTM) on board the Viking 1 and 2 Orbiters.
Thermophysics | Remote sensing
On July 29, 1969, less than a week before closest approach, Jet Propulsion Laboratory (JPL) lost contact with Mariner 7. The center regained the signal via the backup low-gain antenna and regained use of the high gain antenna again shortly after Mariner 6's close encounter. Leaking gases from a battery (which later failed) were thought to have caused the anomaly. Based on the observations that Mariner 6 made, Mariner 7 was reprogrammed in flight to take further observations of areas of interest and actually returned more pictures than Mariner 6, despite the battery's failure. Closest approach for Mariner 6 occurred July 31, 1969, at 05:19:07 UT at a distance of above the martian surface.
Mariner 6 and 7 | Spaceflight
Further observations were made using the Las Cumbres Observatory 1m at CTIO 24.7 hours after discovery which recovered ASASSN1 at a g-band magnitude of 15.2. ASASSN1 was then found 0.77 degrees away from ASASSN1's original location 35.7 hours after discovery. ASAS-SN's Cassius unit re-observed this field 3 days after discovery and found that ASASSN1 significantly brightened to V band 11.9 magnitude. In addition to brightening, the coma around ASASSN1 also increased significantly to 2.5 arcmin. Finally, the northern ASAS-SN unit, a quadruple 14-cm "Brutus" telescope on Haleakala Hawaii, observed ASASSN1 6 days after discovery and found that ASASSN1 appears to have faded to V~12.2.
ASASSN1 | Discovery
Over 75 gigabytes of scientific data was expected to be yielded during the primary mission, much more than any previous mission to Mars. The end of the operable life for the spacecraft was expected to be limited by the supply of propellant and the condition of the batteries.
Mars Observer | Intended operations
The chemical releases were monitored with optical and radar instrumentation by ground-based observers to measure the bulk properties and movement of the expanding clouds of photo-ionized plasma along field lines after the releases occurred. In order to study the magnetosphere at different local times during the mission, the satellite orbit was designed to precess with respect to the Earth-Sun line such that the local time at apogee decreased by 2.5 minutes/day from 08:00 (LT) just after launch and returned to this position in nineteen month cycles. The CRRES spacecraft had the shape of an octagonal prism with solar arrays on the top side.
CRRES | Introduction
The robotic lunar probes Luna 9, Luna 13, Surveyor 1 and Surveyor 3 landed in Oceanus Procellarum. Luna 9 landed southwest of Galilaei crater in 1966. Luna 13 landed southeast of Seleucus crater, later in 1966. Surveyor 1 landed north of Flamsteed crater (within the larger Flamsteed P) in 1966, and Surveyor 3 landed in 1967. During the Apollo program, flight operations planners were concerned about having the optimum lighting conditions at the landing site, hence the alternative target sites moved progressively westward, following the terminator. A delay of two days for weather or equipment reasons would have sent Apollo 11 to Sinus Medii (designated ALS3) instead of ALS2—Mare Tranquillitatis; another two-day delay would have resulted in ALS5, a site in Oceanus Procellarum, being targeted.
Oceanus Procellarum | Exploration
The mission ended when the probe's attitude control gas ran out on March 24, 1975. As the spacecraft was no longer controllable without its nitrogen gas thrusters, a command was sent to the probe to shut down its transmitter. The close observations collected two important sets of data. The probe detected Mercury's magnetic field, which is very similar to Earth's. This was a surprise to scientists, because Mercury spins so slowly on its axis. Secondly, visual data was provided, which showed the high number of craters on the surface of the planet. The visual data also allowed scientists to determine that Mercury had “not experienced significant crustal modification”.
Exploration of Mercury | "Mariner 10"
During closest approach, the Plasma Subsystem, an instrument designed to detect plasma in the vicinity of the spacecraft, sampled some of the material in the outer halo of the Thor plume, finding "snowflakes" weighing 500-1000 amu. Assuming a pure sulfur dioxide composition, this suggested that the dust particles inferred by the camera's distant observation were made up of 15 to 20 molecules of sulfur dioxide. The Near-infrared Mapping Spectrometer (NIMS) mapped thermal emission and infrared spectra across Io's anti-Jupiter hemisphere shortly after the encounter, and found an intense thermal hotspot at Thor with a near-infrared spectrum consistent with an explosion-dominated eruption.
Thor (volcano) | August 2001
GRB 000131 was detected on 31 January 2000 at 14:59 UTC by Ulysses, KONUS, NEAR Shoemaker, and BATSE. It lasted approximately 90 seconds. The initial position, derived from the observations of all the aforementioned spacecraft, was estimated at a right ascension of and a declination of . On 4 February 2000, optical observations of the region were made by telescopes at Paranal Observatory and La Silla Observatory in Chile which revealed the burst's optical afterglow.
GRB 000131 | Observations
Before the arrival of the Mariner 9 and Viking orbiter spacecraft at Mars, only an estimate of the Mars gravitational constant GM, i.e. the universal constant of gravitation times the mass of Mars, was available for deducing the properties of the Martian gravity field. GM could be obtained through observations of the motions of the natural satellites of Mars (Phobos and Deimos) and spacecraft flybys of Mars (Mariner 4 and Mariner 6). Long term Earth-based observations of the motions of Phobos and Deimos provide physical parameters including semi-major axis, eccentricity, inclination angle to the Laplacian plane etc., which allow calculation of the ratio of solar mass to the mass of Mars, moment of inertia and coefficient of the gravitational potential of Mars, and give initial estimates of the gravity field of Mars.
Gravity of Mars | Earth-based observation
Ten spacecraft have successfully landed on Venus and returned data, all were flown by the Soviet Union. Venera 9, 10, 13, and 14 had cameras and returned images of soil and rock. Spectrophotometry results showed that these four missions kicked up dust clouds on landing, which means that some of the dust particles must be smaller than about 0.02 mm. The rocks at all four sites showed fine layers, some layers were more reflective than others. Experiments on rocks at the Venera 13 and 14 sites found that they were porous and easily crushed (bearing maximum loads of 0.3 to 1 MPa) these rocks may be weakly lithified sediments or volcanic tuff.
Geology of Venus | Surface observations
The Mariner 8 spacecraft was built on an octagonal magnesium frame, 45.7 cm deep and 138.4 cm across a diagonal. Four solar panels, each 215 x 90 cm, extended out from the top of the frame. Each set of two solar panels spanned 6.89 meters from tip to tip. Also mounted on the top of the frame were two propulsion tanks, the maneuver engine, a 1.44 m long low gain antenna mast and a parabolic high gain antenna. A scan platform was mounted on the bottom of the frame, on which were attached the mutually bore-sighted science instruments (wide- and narrow-angle TV cameras, infrared radiometer, ultraviolet spectrometer, and infrared interferometer spectrometer).
Mariner 8 | Spacecraft and subsystems
The "Dawn" mission was designed to study two large bodies in the asteroid belt in order to answer questions about the formation of the Solar System, as well as to test the performance of its ion thrusters in deep space. Ceres and Vesta were chosen as two contrasting protoplanets, the first one apparently "wet" (i.e. icy and cold) and the other "dry" (i.e. rocky), whose accretion was terminated by the formation of Jupiter. The two bodies provide a bridge in scientific understanding between the formation of rocky planets and the icy bodies of the Solar System, and under what conditions a rocky planet can hold water.
Dawn (spacecraft) | Scientific background
The mission would be managed by NASA/JPL. JPL would also build parts of the radar and camera, and provide a mass spectrometer. The spacecraft would be developed by Lockheed Martin and derived from their proven central core cylinder designs. This configuration has been successfully applied on "Mars Reconnaissance Orbiter", "Juno", "MAVEN", and "OSIRIS-REx". The spacecraft would use Ultraflex solar arrays made by Orbital ATK. The Italian Space Agency (ASI) and its contractor Thales would supply the digital portion of the radar altimeter and parts of the telecommunications system. On 20 November 2017 NASA selected two other proposals for additional concept studies: Comet Astrobiology Exploration Sample Return (CAESAR), and Dragonfly).
Oceanus (Titan orbiter) | Proposed development
"Mars Observer" was scheduled to perform an orbital insertion maneuver on August 24, 1993, but contact with the spacecraft was lost on August 21, 1993. The likely reason for the spacecraft failure was the leakage of fuel and oxidizer vapors through the improperly designed PTFE check valve to the common pressurization system. During interplanetary cruise, the vapor mix had accumulated in feed lines and pressurant lines, resulting in explosion and their rupture after the engine was restarted for routine course correction. A similar problem later crippled the Akatsuki space probe in 2010. Although none of the primary objectives were achieved, the mission provided interplanetary cruise phase data, collected up to the date of last contact.
Mars Observer | Encounter with Mars
Mariner 9 was the first to place an infrared radiometer and spectrometer in Mars orbit in 1971, along with its other instruments and radio transmitter. Viking 1 and 2 followed, with not merely Infrared Thermal Mappers (IRTM). The missions could also corroborate these remote sensing datasets with not only their "in situ" lander metrology booms, but with higher-altitude temperature and pressure sensors for their descent. Differing "in situ" values have been reported for the average temperature on Mars, with a common value being . Surface temperatures may reach a high of about at noon, at the equator, and a low of about at the poles.
Climate of Mars | Temperature
During course maneuvers, a spacecraft may need to rotate so that its rocket faces the proper direction before being fired. "Mariner 10" determined its attitude using two optical sensors, one pointed at the Sun, and the other at a bright star, usually Canopus; additionally, the probe's three gyroscopes provided a second option for calculating the attitude. Nitrogen gas thrusters were used to adjust "Mariner 10"s orientation along three axes. The spacecraft's electronics were intricate and complex: it contained over 32,000 pieces of circuitry, of which resistors, capacitors, diodes, microcircuits, and transistors were the most common devices. Commands for the instruments could be stored on "Mariner 10"s computer, but were limited to 512 words.
Mariner 10 | Design and trajectory
Because the spacecraft viewed the same areas from different positions during the first and second passes, stereoscopic pictures are available for certain areas of the southern hemisphere; however, such pictures are not available for the Shakespeare quadrangle. All of the Mariner 10 passes occurred under similar lighting conditions. Across the Shakespeare quadrangle, these conditions varied from low light at the terminator near the west boundary to higher sun at the east boundary. Consequently, lighting conditions were favorable for determining fine-scale relief in the west, but progressively less so toward the east. Conversely, albedo features such as bright crater rays, which are conspicuous in the eastern part, become increasingly difficult to recognize westward toward the terminator.
Shakespeare quadrangle | Mariner 10 imaging
The on-board computer also experienced unscheduled resets occasionally, which necessitated reconfiguring the clock sequence and subsystems. Periodic problems with the high-gain antenna also occurred during the cruise. On 8 January 1974, a malfunction thought to be caused by a short-circuited diode occurred in the power subsystem. As a result, the main booster regulator and inverter failed, leaving the spacecraft dependent on the redundant regulator. Mission planners feared that the same problem could recur in the redundant system and cripple the spacecraft. In January 1974, "Mariner 10" made ultraviolet observations of Comet Kohoutek. Another mid-course correction was made on 21 January 1974.
Mariner 10 | Cruise to Venus
During Apollo 14, the crew members sampled ejecta from Cone crater, a feature close in proximity to the immediate landing site of the mission, which provided insight into the composition of material deep inside the formation. Data from the mission has helped to determine the approximate age of Mare Imbrium, suggesting that it is no more than about 4.25 billion years old.
Fra Mauro formation | Introduction
Spectrometry found that the surface materials at the Venera 9, 10, 14 and Vega 1 and 2 landing had chemical compositions similar to tholeiitic basalts, while the Venera 8 and 13 sites chemically resembled alkaline basalts.
Geology of Venus | Surface observations
The Mars Observer spacecraft, also known as the Mars Geoscience/Climatology Orbiter, was a robotic space probe launched by NASA on September 25, 1992, to study the Martian surface, atmosphere, climate and magnetic field. During the interplanetary cruise phase, communication with the spacecraft was lost on August 21, 1993, three days prior to orbital insertion. Attempts to re-establish communication with the spacecraft were unsuccessful.
Mars Observer | Introduction
Due to the Atlas-Agena putting Mariner slightly off course, the spacecraft required a mid-course correction, consisting of a roll-turn sequence, followed by a pitch-turn sequence and finally a motor-burn sequence. Preparation commands were sent to the spacecraft at 21:30 UTC on September 4. Initiation of the mid-course maneuver sequence was sent at 22:49:42 UTC and the roll-turn sequence started one hour later. The entire maneuver took approximately 34 minutes. Due to the mid-course maneuver, the sensors lost their lock with the Sun and Earth. At 00:27:00 UTC the Sun re-acquisition began and at 00:34 UTC the Sun was reacquired. Earth re-acquisition started at 02:07:29 UTC and Earth was reacquired at 02:34 UTC.
Mariner 2 | Mid-course maneuver
was first observed on 17 March 2015, by a team of astronomers led by Scott Sheppard of the Carnegie Institution for Science as part of the survey for distant solar system objects beyond the Kuiper Cliff using the new wide-field cameras on the Subaru and Cerro Tololo Inter-American Observatory (CTIO) telescopes.
2015 FJ345 | Discovery and naming
All images were transmitted twice to ensure no data was missing or corrupt. Each individual photograph took approximately six hours to be transmitted back to Earth. The spacecraft performed all programmed activities successfully and returned useful data from launch until 22:05:07 UT on October 1, 1965, when the long distance to Earth (309.2 million km) and the imprecise antenna orientation led to a temporary loss of communication with the spacecraft until 1967.
Mariner 4 | Mars flyby
Solar pressure vanes, each with an area of 0.65 square meter (seven ft²), were attached to the tips of the solar panels. Positional information was provided by four Sun sensors, and a sensor for either the Earth, Mars, or the star Canopus, depending on the time in its spaceflight. Mariner 4 was the first space probe that needed a star for a navigational reference object, since earlier missions, which remained near either the Earth, the Moon, or the planet Venus, had sighted onto either the bright face of the home planet or the brightly lit target. During this flight, both the Earth and Mars would be too dim to lock onto.
Mariner 4 | Spacecraft and subsystems
In planetary science, NICMOS was used to discover an impact basin on the south pole of the asteroid 4 Vesta. (4 Vesta was later visited by Dawn (spacecraft) in the 2010s which investigated it more closely by orbiting it.) In 2009, an old NICMOS image was processed to show a predicted exoplanet around the star HR 8799. The system is thought to be about 130 light-years from Earth.
Near Infrared Camera and Multi-Object Spectrometer | Scientific results
"Opportunity" observed the eclipse, or transits of Phobos and transits of Deimos across the Sun, and photographed the Earth, which appeared as a bright celestial object in the Martian sky. A transit of Mercury from Mars took place on January 12, 2005 from about 14:45 UTC to 23:05 UTC, but camera resolution did not permit seeing Mercury's 6.1" angular diameter. Transits of Deimos across the Sun were seen, but at 2' angular diameter, Deimos is about 20 times larger than Mercury's 6.1" angular diameter.
Scientific information from the Mars Exploration Rover mission | Astronomical observations
was first observed on 24 March 2014 by a team of astronomers led by Scott Sheppard of the Carnegie Institution for Science as part of the survey for distant solar system objects beyond the Kuiper Cliff using the new wide-field cameras on the Subaru and Cerro Tololo Inter-American Observatory (CTIO) telescopes.
2014 FZ71 | Discovery and naming
These instruments were designed to measure the temperature distribution on the surface of Venus and to make basic measurements of Venus' atmosphere. The primary mission was to receive communications from the spacecraft in the vicinity of Venus and to perform radiometric temperature measurements of the planet. A second objective was to measure the interplanetary magnetic field and charged particle environment.
Mariner 2 | Introduction
2MASS 0243−2453 was discovered in 2002 by Adam J. Burgasser et al. from Two Micron All-Sky Survey (2MASS), conducted from 1997 to 2001. Follow-up observations were made in 1998–2001 using the Near-Infrared Camera, mounted on the Palomar 60 inch (1.5 m) Telescope; CTIO Infrared Imager (CIRIM) and Ohio State Infrared Imager/Spectrometer (OSIRIS), mounted on the Cerro Tololo Inter-American Observatory (CTIO) 1.5 m Telescope; and some additional observations were made using the Near Infrared Camera (NIRC), mounted on the Keck I 10 m telescope, and nearinfrared camera D78, mounted on the Palomar 5 m Hale Telescope. In 2002 Burgasser et al.
2MASS J02431371−2453298 | Discovery
Hall recorded his discovery of Phobos in his notebook as follows: The telescope used for the discovery was the 26-inch (66 cm) refractor (telescope with a lens) then located at Foggy Bottom. In 1893 the lens was remounted and put in a new dome, where it remains into the 21st century.
Moons of Mars | Discovery
Despite the lack of close-up imaging and mechanical problems that greatly restricted the amount of data returned, several significant discoveries were made during "Galileo" primary mission. "Galileo" observed the effects of a major eruption at Pillan Patera and confirmed that volcanic eruptions are composed of silicate magmas with magnesium-rich mafic and ultramafic compositions. Distant imaging of Io was acquired for almost every orbit during the primary mission, revealing large numbers of active volcanoes (both thermal emission from cooling magma on the surface and volcanic plumes), numerous mountains with widely varying morphologies, and several surface changes that had taken place both between the "Voyager" and "Galileo" eras and between "Galileo" orbits.
Io (moon) | "Galileo"
Engineers initially feared that the star-tracker could mistake the much brighter Venus for Canopus, repeating the mishaps with flaking paint. However, the star-tracker did not malfunction. Earth occultation occurred between 17:07 and 17:11 UTC, during which the spacecraft transmitted X-band radio waves through Venus' atmosphere, gathering data on cloud structure and temperature. Although Venus's cloud cover is nearly featureless in visible light, it was discovered that extensive cloud detail could be seen through Mariner's ultraviolet camera filters. Earth-based ultra-violet observation had shown some indistinct blotching even before "Mariner 10", but the detail seen by Mariner was a surprise to most researchers.
Mariner 10 | Venus flyby
The "Clementine" Near-Infrared camera (NIR) was designed to study the surfaces of the Moon and the near-Earth asteroid 1620 Geographos at six different wavelengths in the near-infrared spectrum. This experiment yielded information on the petrology of the surface material on the Moon. The rendezvous with Geographos was canceled due to equipment malfunction. The camera consisted of a catadioptric lens which focused on a mechanically cooled (to a temperature of 70 [[Kelvin|K]]) Amber InSb CCD focal-plane array with a bandpass of 1100–2800 nm and a six-position filter wheel. The filter center wavelengths (and bandpass widths (FWHM)) were: 1100 nm (60 nm), 1250 nm (60 nm), 1500 nm (60 nm), 2000 nm (60 nm), 2600 nm (60 nm), and 2780 nm (120 nm).
Clementine (spacecraft) | Near-Infrared CCD Camera (NIR)
Being an ever-changing scientific target, Jupiter has been observed intermittently since the end of the "Galileo" mission in September 2003. Knowledge about Jupiter benefited from the fact that "New Horizons" instruments were built using the latest technology, especially in the area of cameras, representing a significant improvement over "Galileo" cameras, which were modified versions of "Voyager" cameras, which, in turn, were modified "Mariner" cameras. The Jupiter encounter also served as a shakedown and dress rehearsal for the Pluto encounter. Because Jupiter is much closer to Earth than Pluto, the communications link can transmit multiple loadings of the memory buffer; thus the mission returned more data from the Jovian system than it was expected to transmit from Pluto.
New Horizons | Jupiter encounter
Careful and continuous photographic observation of the satellite allowed scientists to conduct an unprecedented survey of the Earth's exosphere. The satellite first confirmed the daily bulge in the upper atmosphere caused by the sun's heating the air during the day and verified the model of exospheric temperature developed according to other satellite data. It was later discovered that the temperature of the exosphere increased after geomagnetic disturbances in the ionosphere, peaking around five hours after each event. With three years of data, scientists were able to discern a seasonal variation to the exosphere's density, with an increase of 25% observed in winter over summer at a reference latitude of 39 degrees.
Explorer 9 | Mission results
Measurements made with the IRAS observatory give a diameter of 169.92 ± 7.86 km and a geometric albedo of 0.07 ± 0.01. By comparison, the MIPS photometer on the Spitzer Space Telescope gives a diameter of 168.72 ± 8.89 km and a geometric albedo of 0.07 ± 0.01. When the asteroid was observed occulting a star, the results showed a diameter of 176.7 ± 0.4 km.
106 Dione | Introduction
The Atlas stage burned for around four minutes, after which it was jettisoned, and the Centaur stage took over for an additional five minutes, propelling "Mariner 10" to a parking orbit. The temporary orbit took the spacecraft one-third of the distance around Earth: this maneuver was needed to reach the correct spot for a second burn by the Centaur engines, which set "Mariner 10" on a path towards Venus. The probe then separated from the rocket; subsequently, the Centaur stage diverted away to avoid the possibility of a future collision. Never before had a planetary mission depended upon two separate rocket burns during the launch, and even with "Mariner 10", scientists initially viewed the maneuver as too risky.
Mariner 10 | Departing Earth
Copernicus made three observations of Mercury, with errors of −3, −15 and −1 minutes of arc. He made one of Venus, with an error of −24 minutes. Four were made of Mars, with errors of 2, 20, 77, and 137 minutes. Four observations were made of Jupiter, with errors of 32, 51, −11 and 25 minutes. He made four of Saturn, with errors of 31, 20, 23 and −4 minutes.
Nicolaus Copernicus | Planetary observations
OSSOS observed eight blocks of the sky over a period of five years from 2013–2017 using the MegaPrime camera of the 3.6 m Canada-France-Hawaii Telescope. Images of these blocks were taken near opposition (when the block is near opposite the sun), two months before, and two months after. This extended period of observation was designed to remove ephemeris bias which can cause the loss of some objects due to inaccurate predictions of their future positions. Pointing directions, detection efficiencies, and tracking frequencies were determined to allow other observational biases to be identified. These identified biases are used by the survey simulator developed by the OSSOS group.
Outer Solar System Origins Survey | Description
The mission would have also returned images of Mars' surface.
Nozomi (spacecraft) | Introduction
The overall height of the spacecraft was 2.28 m. The launch mass was 997.9 kg, of which 439.1 kg were expendables. The science instrumentation had a total mass of 63.1 kg. The electronics for communications and command and control were housed within the frame. Spacecraft power was provided by a total of 14,742 solar cells which made up the 4 solar panels with a total area of 7.7 square meters area. The solar panels could produce 800 W at Earth and 500 W at Mars. Power was stored in a 20 ampere hour nickel-cadmium battery. Propulsion was provided by a gimbaled engine capable of 1340 N thrust and up to 5 restarts.
Mariner 8 | Spacecraft and subsystems
During September and October 1960, the first 130 photographic plates were taken, with each plate spanning and having a limiting magnitude of 20.5. The observed region covered an area of . The Zeiss blink comparator from the Heidelberg Observatory was adapted to perform blink comparison of the plates. This resulted in the discovery of a large number of asteroids; typically 200–400 per plate. A subset of these objects had sufficient data to allow orbital elements to be computed. The mean error in their positions was as small as 0.6″, which corresponded to 0.009 mm on the plates. The resulting mean error in magnitude estimation was 0.19.
Palomar–Leiden survey | Original PLS-survey
However the observation was excluded from the asteroid's orbit determination and did not extend its observation arc prior to its discovery.
7835 Myroncope | Classification and orbit
Photometric observations of this asteroid during 1997 were used to build a lightcurve showing a rotation period of hours with a brightness variation of magnitude. A 2009 study yielded a period of hours, in reasonable agreement with the previous result.
911 Agamemnon | Rotation period
Mariner 8 and Mariner 9 were identical sister craft designed to map the Martian surface simultaneously, but Mariner 8 was lost in a launch vehicle failure. Mariner 9 was launched in May 1971 and became the first artificial satellite of Mars. Its launch mass was nearly doubled by the onboard rocket propellant needed to thrust it into orbit around Mars, but otherwise it closely resembled its predecessors. It entered Martian orbit in November 1971 and began photographing the surface and analyzing the atmosphere with its infrared and ultraviolet instruments. Status:
Mariner program | Mariners 8 and 9
The Copernicus ejecta sampled suggested that the Copernicus impact occurred about 800 million years ago, but geologists believe the results of this analysis are inconclusive. The Apollo 12 astronauts also noted the existence of small, shallow elongated depressions ("trenches" or "grooves") similar to those the Apollo 11 astronauts observed at Tranquility Base in the Sea of Tranquility; Shoemaker et al. preliminarily concluded in 1970 that these features reflected the direction and location of fractures in the underlying bedrock, into which fine-grained material settled, thereby creating the grooves. Overall, Statio Cognitum and the surrounding area appears to have a slightly more red coloration from lunar orbit than Tranquility Base (which geologists later found to be the result of less titanium in the Apollo 12 rocks) and to have fewer craters overall than Tranquility Base; because of this, geologists suspected the site chosen for Apollo 12 contained younger rocks than those of the Apollo 11 site, and this was confirmed by the samples returned by Apollo 12.
Mare Cognitum | Statio Cognitum
However, the variations in the solar constant that Abbot derived from the results of his other solar observatories never convinced most meteorologists either, and were ascribed to uncorrected variations in atmospheric absorption.
Brukkaros Solar Observatory | Evaluation of the observatory's work
This data would be useful for subsequent missions to Mars. Science instruments originally developed for "Mars Observer" were placed on four subsequent spacecraft to complete the mission objectives: Mars Global Surveyor launched in 1996, Mars Climate Orbiter launched in 1998, 2001 Mars Odyssey launched in 2001 and Mars Reconnaissance Orbiter launched in 2005.
Mars Observer | Encounter with Mars
The trajectory made it possible to also observe asteroids 951 Gaspra and 243 Ida. "Galileo" had two major components: an orbiter which examined Jupiter and its four largest moons for eight years, and a probe which descended into the Jovian atmosphere to take direct samplings before being destroyed by the gas giant's heat and pressure. Besides the "Galileo" spacecraft, "Atlantis"' payload bay held two canisters containing the Shuttle Solar Backscatter Ultraviolet (SSBUV) experiment. SSBUV, which made its first flight on STS-34, was developed by NASA to check the calibration of the ozone sounders on free-flying satellites, and to verify the accuracy of atmospheric ozone and solar irradiance data.
STS-34 | Payload and experiments