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45-614: SHARAD was developed under the responsibility of the Italian Space Agency (ASI, Agenzia Spaziale Italiana), and provided to JPL for use on board NASA's Mars Reconnaissance Orbiter spacecraft in the frame of a NASA/ASI agreement which foresees exploitation of the data by a joint Italian/US team. The INFOCOM dept. of the University of Sapienza University of Rome is responsible for the instrument operations, while Thales Alenia Space Italia (formerly Alenia Spazio) designed and built

90-550: A mobile rigid platform located close to the equator. This station, composed of 3 oil platforms and two logistical support boats, was installed off the Kenya coast, close to the town of Malindi . Italy would later launch further satellites in the series (San Marco 2 in 1967, San Marco 3 in 1971, San Marco 4 in 1974 and San Marco D/L in 1988 ) using the American Scout rockets like the original, but from its own spaceport. As one of

135-450: A communications ground station. One further balloon launch base located in Trapani was permanently closed in 2010. In 2020, ASI's annual revenues budget was approximately €2.0 billion and it directly employed around 200 workers. Activities started officially in 1988 but the agency drew extensively on the work of earlier national organisations as well as the consolidated experience of

180-659: A key function in storing equipment and parts for transfer to the International Space Station . A number of ISS modules have also been made in Italy. As part of ESA's contribution to the costs of the International Space Station, Alcatel Alenia Space manufactured Tranquility , Harmony as well as the Cupola observation deck for NASA. ESA's Columbus module, Western Europe's primary scientific lab on board

225-459: A priori knowledge of the surface topography, is the nominal means to position the 135 μs receive window on the expected echo position (a closed-loop tracker is available as backup). The instrument on-board signal processing is minimal, and consists of a coherent presumption of the received echoes (programmable between 1 and 32 in power of 2 steps) to reduce the generated data rate, with programmable number of bits (8, 6, 4). The chirp signal

270-801: A subduction zone cannot subduct much further than about 100 km (62 mi) before resurfacing. As a result, continental lithosphere is not recycled at subduction zones the way oceanic lithosphere is recycled. Instead, continental lithosphere is a nearly permanent feature of the Earth. Geoscientists can directly study the nature of the subcontinental mantle by examining mantle xenoliths brought up in kimberlite , lamproite , and other volcanic pipes . The histories of these xenoliths have been investigated by many methods, including analyses of abundances of isotopes of osmium and rhenium . Such studies have confirmed that mantle lithospheres below some cratons have persisted for periods in excess of 3 billion years, despite

315-671: Is a partner in the Ariane 5 launcher programme and more recently is the major (65%) backer of the ESA Vega small launcher, capable of putting a payload of 1500 kg to low Earth orbit . ASI is a participant in many of ESA's programmes in the field of Earth Observation such as ERS-1 , ERS-2 , ENVISAT , the Meteosat series and the Galileo satellite navigation system. The agency has also collaborated with other European and international partners such as

360-415: Is a thermal boundary layer for the convection in the mantle. The thickness of the mantle part of the oceanic lithosphere can be approximated as a thermal boundary layer that thickens as the square root of time. h ∼ 2 κ t {\displaystyle h\,\sim \,2\,{\sqrt {\kappa t}}} Here, h {\displaystyle h} is the thickness of

405-912: Is composed as follows: While the initial studies date back to 2001, full-scale development was released only in February 2003. The Engineering Model (EM) of the instrument was delivered to Lockheed Martin Space Systems in Denver (responsible for the spacecraft) in March 2004, and integrated into the Orbiter Test Bed. The ProtoFlight Model (PFM) was delivered and integrated on the Mars Reconnaissance Orbiter in Denver in September 2004. Mars Reconnaissance Orbiter

450-466: Is generated directly on the 20 MHz carrier by a digital chirp generator and fed to the power amplifier, followed by a Transmit/Receive switch and the matching network . The receiver provides amplification, filtering and digital gain control directly at RF, and the digitised using an undersampling technique at a rate of 26.6 MHz. A single digital signal processor provides both the control and processing function. The instrument industrial team

495-417: Is no thicker than the crust, but oceanic lithosphere thickens as it ages and moves away from the mid-ocean ridge. The oldest oceanic lithosphere is typically about 140 kilometres (87 mi) thick. This thickening occurs by conductive cooling, which converts hot asthenosphere into lithospheric mantle and causes the oceanic lithosphere to become increasingly thick and dense with age. In fact, oceanic lithosphere

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540-408: Is the rigid, outermost rocky shell of a terrestrial planet or natural satellite . On Earth , it is composed of the crust and the lithospheric mantle , the topmost portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more. The crust and upper mantle are distinguished on the basis of chemistry and mineralogy . Earth's lithosphere, which constitutes

585-426: Is velocity of the lithospheric plate. Oceanic lithosphere is less dense than asthenosphere for a few tens of millions of years but after this becomes increasingly denser than asthenosphere. While chemically differentiated oceanic crust is lighter than asthenosphere, thermal contraction of the mantle lithosphere makes it more dense than the asthenosphere. The gravitational instability of mature oceanic lithosphere has

630-587: The Indian Space Research Organisation (ISRO) in 2007. A particular innovation was the use of a single instrument to measure both Gamma rays and hard X-rays. ASI also has collaborated on many major international space exploration missions including; Italy's space industry has also been involved in many other scientific missions such as SOHO , Cluster II , ISO , XMM-Newton and Planck . The technology experiments TSS-1 and TSS-1R were also conducted in partnership with NASA. Currently ASI

675-564: The Shuttle Radar Topography Mission with NASA. In October 1992, NASA launched LAGEOS-2 (following LAGEOS-1 launched in 1976) in cooperation with ASI. A passive satellite, it is an aluminum plated brass sphere covered with retroreflectors to reflect laser ranging beams emitted from ground stations on Earth. The primary mission goals were to determine accurately Earth's Geoid and to measure Tectonic plate movement. In 2010 ASI's own satellite, LARES , will be launched using

720-536: The Utopia Planitia region of Mars using SHARAD. The volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior . The calculations for the volume of water ice in the region were based on measurements from SHARAD, the ground-penetrating radar instrument on the Mars Reconnaissance Orbiter (MRO). SHARAD radar data when combined to form a 3D model reveal buried craters in

765-426: The ocean basins . Continental lithosphere is associated with continental crust (having a mean density of about 2.7 grams per cubic centimetre or 0.098 pounds per cubic inch) and underlies the continents and continental shelves. Oceanic lithosphere consists mainly of mafic crust and ultramafic mantle ( peridotite ) and is denser than continental lithosphere. Young oceanic lithosphere, found at mid-ocean ridges ,

810-583: The Centro Ricerche Aerospaziali, the aerospace research group of the University of Rome La Sapienza . This plan, conceived by Luigi Broglio, led to the San Marco programme of Italian-built satellites beginning with the launch of Italy's first satellite, San Marco 1 , from Wallops Island . The San Marco project since 1967 was focused on the launching of scientific satellites by Scout rockets from

855-438: The Earth." They have been broadly accepted by geologists and geophysicists. These concepts of a strong lithosphere resting on a weak asthenosphere are essential to the theory of plate tectonics . The lithosphere can be divided into oceanic and continental lithosphere. Oceanic lithosphere is associated with oceanic crust (having a mean density of about 2.9 grams per cubic centimetre or 0.10 pounds per cubic inch) and exists in

900-600: The ISS, was again built in Turin based on Italy's previous experience in space station module construction. As an ESA member heavily involved in human spaceflight, ASI sponsors a select few Italian citizens to train at ESA's European Astronaut Corps (EAC) to represent the country on missions. Italians to have flown in space are: Lithosphere A lithosphere (from Ancient Greek λίθος ( líthos )  'rocky' and σφαίρα ( sphaíra )  'sphere')

945-684: The National Aerospace Plan and ensuring it is carried out. To do this the agency operates as the owner/coordinator of a number of Italian space research agencies and assets such as CIRA as well as organising the calls and opportunities process for Italian industrial contractors on spaceflight projects. Internationally, the ASI provides Italy's delegation to the Council of the European Space Agency and to its subordinate bodies as well as representing

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990-544: The National Research Council including the launch of an indigenous telecoms /research satellite called SIRIO-1 in 1977. A planned follow-up mission SIRIO-2 was destroyed in the Ariane 1 L-05 launch failure. During the 1980s, it became clear of the need to rationalise and strengthen Italy's position in space research and so the decision was made to create the Italian Space Agency to further coordinate

1035-754: The Vega rocket. The mission is designed to carry out similar studies to that of LAGEOS 2 but with much greater precision. The Italian Space Agency, under direction of both the Ministry of Research and the Ministry of Defence , developed the COSMO-SkyMed constellation of satellites for both military and civilian use in a broad range of areas. The Italian Space Agency launched in 2019 the multimission program PLATiNO (mini Piattaforma spaziaLe ad Alta TecNOlogia, High-Technology Mini-Satellite Platform), to develop industrial capability in

1080-419: The asthenosphere deforms viscously and accommodates strain through plastic deformation . The thickness of the lithosphere is thus considered to be the depth to the isotherm associated with the transition between brittle and viscous behavior. The temperature at which olivine becomes ductile (~1,000 °C or 1,830 °F) is often used to set this isotherm because olivine is generally the weakest mineral in

1125-431: The climate changed. Italian Space Agency The Italian Space Agency ( Italian : Agenzia Spaziale Italiana ; ASI ) is a government agency established in 1988 to fund, regulate and coordinate space exploration activities in Italy. The agency cooperates with numerous national and international entities who are active in aerospace research and technology. Nationally, ASI is responsible for both drafting

1170-518: The concept and introduced the term "lithosphere". The concept was based on the presence of significant gravity anomalies over continental crust, from which he inferred that there must exist a strong, solid upper layer (which he called the lithosphere) above a weaker layer which could flow (which he called the asthenosphere ). These ideas were expanded by the Canadian geologist Reginald Aldworth Daly in 1940 with his seminal work "Strength and Structure of

1215-408: The continental lithosphere are billions of years old. Geophysical studies in the early 21st century posit that large pieces of the lithosphere have been subducted into the mantle as deep as 2,900 kilometres (1,800 mi) to near the core-mantle boundary, while others "float" in the upper mantle. Yet others stick down into the mantle as far as 400 kilometres (250 mi) but remain "attached" to

1260-403: The continental plate above, similar to the extent of the old concept of "tectosphere" revisited by Jordan in 1988. Subducting lithosphere remains rigid (as demonstrated by deep earthquakes along Wadati–Benioff zone ) to a depth of about 600 kilometres (370 mi). Continental lithosphere has a range in thickness from about 40 kilometres (25 mi) to perhaps 280 kilometres (170 mi);

1305-672: The country's interests in foreign collaborations. ASI's main headquarters are located in Rome, Italy , and the agency also has direct control over two operational centres: the Centre for Space Geodesy (CGS) located in Matera in Italy, and its own spaceport, the Broglio Space Centre (formerly the San Marco Equatorial Range ) on the coastal sublittoral of Kenya , currently used only as

1350-568: The earliest countries to be engaged in space exploration, Italy became a founder and key partner in the European Launcher Development Organisation (ELDO) and the European Space Research Organisation (ESRO), established on 29 March and 14 June 1962 respectively. Both of these would later merge to form the European Space Agency on 30 April 1975. Further work would continue under the direction of

1395-437: The effect that at subduction zones, oceanic lithosphere invariably sinks underneath the overriding lithosphere, which can be oceanic or continental. New oceanic lithosphere is constantly being produced at mid-ocean ridges and is recycled back to the mantle at subduction zones. As a result, oceanic lithosphere is much younger than continental lithosphere: the oldest oceanic lithosphere is about 170 million years old, while parts of

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1440-559: The hard and rigid outer vertical layer of the Earth, includes the crust and the lithospheric mantle (or mantle lithosphere), the uppermost part of the mantle that is not convecting. The lithosphere is underlain by the asthenosphere which is the weaker, hotter, and deeper part of the upper mantle that is able to convect. The lithosphere–asthenosphere boundary is defined by a difference in response to stress. The lithosphere remains rigid for very long periods of geologic time in which it deforms elastically and through brittle failure, while

1485-575: The instruments. SHARAD operations are managed by INFOCOM from the SHARAD Operation Centre (SHOC), located within the Alcatel Alenia Space facilities in the suburbs of Rome . SHARAD is intended to map the first kilometer below the Mars surface, providing images of subsurface scattering layers with high vertical resolution (15 m), with the intent to locate water/ice deposits and to map

1530-656: The many Italian scientists that had been investigating space and astronautics since the end of the 19th century. Some of the most outstanding names in Italian space exploration since its inception were the following: Early Italian space efforts during the Space Race era were built around cooperation between the Italian Space Commission (a branch of the National Research Council ) and NASA supported primarily by

1575-576: The nation's space activities. ASI's first large scientific satellite mission was BeppoSAX , developed in collaboration with the Netherlands and launched in 1996. Named after Giuseppe “Beppo” Occhialini , an important figure in Italian high-energy physics, the satellite was a mission to study the universe in the X-ray part of the spectrum. Following on from this ASI developed another high-energy astronomical satellite, AGILE for gamma ray astronomy, launched by

1620-455: The north polar cap. These may be used to date certain layers. Research, published in April 2011, described a large deposit of frozen carbon dioxide near the south pole. Most of this deposit probably enters Mars' atmosphere when the planet's tilt increases. When this occurs, the atmosphere thickens, winds get stronger, and larger areas on the surface can support liquid water. After more analysis, it

1665-420: The north polar layered ice deposits of Mars and revealed a relatively small (about 100 meter) maximum deflection of the underlying rock, which suggests a strong lithosphere greater than 300 kilometers thick. Radar results consistent with massive deposits of water ice in middle latitudes support a debris-covered glacier hypothesis. On November 22, 2016, NASA reported finding a large amount of underground ice in

1710-419: The oceanic mantle lithosphere, κ {\displaystyle \kappa } is the thermal diffusivity (approximately 1.0 × 10  m /s or 6.5 × 10  sq ft/min) for silicate rocks, and t {\displaystyle t} is the age of the given part of the lithosphere. The age is often equal to L/V, where L is the distance from the spreading centre of mid-oceanic ridge , and V

1755-597: The small satellites sector. The first mission in 2023 will embark a SAR, the second one in 2024 a Thermal Infrared Imager. Through ASI, the Italian space industry is an active player in human spaceflight activities. The three Space Shuttle Multi-Purpose Logistics Module cargo containers Leonardo , Raffaello and Donatello , were manufactured at the Cannes Mandelieu Space Center in Turin , Italy by Alcatel Alenia Space, now Thales Alenia Space . They provide

1800-424: The unwanted surface returns from off- nadir scatterers at the same range of the subsurface echoes. SHARAD is physically divided into two elements: The instrument operates at fixed PRF (700.28 Hz) and the echo is received in rank 1 (i.e., after the second transmitted pulse). Two alternate (higher and lower) PRF are available to deal with the extended mission orbit range. An open-loop tracking system, based on

1845-601: The upper approximately 30 to 50 kilometres (19 to 31 mi) of typical continental lithosphere is crust. The crust is distinguished from the upper mantle by the change in chemical composition that takes place at the Moho discontinuity . The oldest parts of continental lithosphere underlie cratons , and the mantle lithosphere there is thicker and less dense than typical; the relatively low density of such mantle "roots of cratons" helps to stabilize these regions. Because of its relatively low density, continental lithosphere that arrives at

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1890-524: The upper mantle. The lithosphere is subdivided horizontally into tectonic plates , which often include terranes accreted from other plates. The concept of the lithosphere as Earth's strong outer layer was described by the English mathematician A. E. H. Love in his 1911 monograph "Some problems of Geodynamics" and further developed by the American geologist Joseph Barrell , who wrote a series of papers about

1935-399: The vertical structure of the upper subsurface layers. SHARAD operates on a carrier frequency of 20 MHz, transmitting a " chirped " signal with a bandwidth of 10 MHz. Pulsewidth is 85 μs and the nominal Pulse Repetition Frequency is 700.28 Hz. Transmitted power is 10 W peak. The antenna is a 10 m dipole. A synthetic aperture is generated on-ground to reduce

1980-453: Was discovered that if these deposits were all changed into gas, the atmospheric pressure on Mars doubles. There are three layers of these deposits; each are capped with a 30-meter layer of water ice that prevents the CO 2 from sublimating into the atmosphere. In sublimation a solid material goes directly into a gas phase. These three layers are linked to periods when the atmosphere collapsed when

2025-530: Was launched from Cape Canaveral Air Force Station on August 12, 2005, with an Atlas V - Centaur launch vehicle, and reached Mars orbit on March 10, 2006. The aerobraking phase, needed to reach the operational orbit, lasted until August 30, 2006. On September 17, 2006, the SHARAD antenna was deployed, and the first in-flight test of the radar was successfully carried out on September 19. SHARAD has been operational since November 2006. The SHARAD radar penetrated

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