1.
Astronomy
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Astronomy is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry, in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, moons, stars, galaxies, and comets, while the phenomena include supernovae explosions, gamma ray bursts, more generally, all astronomical phenomena that originate outside Earths atmosphere are within the purview of astronomy. A related but distinct subject, physical cosmology, is concerned with the study of the Universe as a whole, Astronomy is the oldest of the natural sciences. The early civilizations in recorded history, such as the Babylonians, Greeks, Indians, Egyptians, Nubians, Iranians, Chinese, during the 20th century, the field of professional astronomy split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects, theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. The two fields complement each other, with theoretical astronomy seeking to explain the results and observations being used to confirm theoretical results. Astronomy is one of the few sciences where amateurs can play an active role, especially in the discovery. Amateur astronomers have made and contributed to many important astronomical discoveries, Astronomy means law of the stars. Astronomy should not be confused with astrology, the system which claims that human affairs are correlated with the positions of celestial objects. Although the two share a common origin, they are now entirely distinct. Generally, either the term astronomy or astrophysics may be used to refer to this subject, however, since most modern astronomical research deals with subjects related to physics, modern astronomy could actually be called astrophysics. Few fields, such as astrometry, are purely astronomy rather than also astrophysics, some titles of the leading scientific journals in this field includeThe Astronomical Journal, The Astrophysical Journal and Astronomy and Astrophysics. In early times, astronomy only comprised the observation and predictions of the motions of objects visible to the naked eye, in some locations, early cultures assembled massive artifacts that possibly had some astronomical purpose. Before tools such as the telescope were invented, early study of the stars was conducted using the naked eye, most of early astronomy actually consisted of mapping the positions of the stars and planets, a science now referred to as astrometry. From these observations, early ideas about the motions of the planets were formed, and the nature of the Sun, Moon, the Earth was believed to be the center of the Universe with the Sun, the Moon and the stars rotating around it. This is known as the model of the Universe, or the Ptolemaic system. The Babylonians discovered that lunar eclipses recurred in a cycle known as a saros
2.
Leicester
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Leicester is a city and unitary authority area in the East Midlands of England, and the county town of Leicestershire. The city lies on the River Soar and at the edge of the National Forest, in the 2011 census the population of the City of Leicester unitary authority was 329,839 making it the most populous municipality in the East Midlands region. The associated urban area is also the 11th most populous in England, the name of Leicester is recorded in the 9th-century History of the Britons as Cair Lerion, and in the Anglo-Saxon Chronicle as Ligora-ceastre. In the Domesday Book of 1086, it is recorded as Ledecestre, the second element of the name comes from the Latin castrum which is reflected in both Welsh cair and Anglo-Saxon ceastre. Based on the Welsh name, Geoffrey of Monmouth proposes a king Leir of Britain as a founder in his Historia Regum Britanniae. Leicester is one of the oldest cities in England, with a going back at least two millennia. The native Iron Age settlement encountered by the Romans at the seems to have developed in the 2nd or 1st centuries BC. This area of the Soar was split into two channels, a stream to the east and a narrower channel on the west. The settlement seems to have controlled a ford across the larger channel, the later Roman name was a latinate form of the Brittonic word for ramparts, suggesting the site was an oppidum. The plural form of the name suggests it was composed of several villages. The Celtic tribe holding the area was recorded as the Coritanians. The Corieltauvians are believed to have ruled over roughly the area of the East Midlands and it is believed that the Romans arrived in the Leicester area around AD47, during their conquest of southern Britain. The Corieltauvian settlement lay near a bridge on the Fosse Way, in the 2nd century, it received a forum and bathhouse. In 2013, the discovery of a Roman cemetery found just outside the old city walls, the remains of the baths of Roman Leicester can be seen at the Jewry Wall, recovered artifacts are displayed at the adjacent museum. Knowledge of the following the Roman withdrawal from Britain is limited. Certainly there is continuation of occupation of the town, though on a much reduced scale in the 5th and 6th centuries. Its memory was preserved as the Cair Lerion of the History of the Britons, following the Saxon invasion of Britain, Leicester was occupied by the Middle Angles and subsequently administered by the kingdom of Mercia. It was elevated to a bishopric in either 679 or 680, this see survived until the 9th century and their settlement became one of the Five Burghs of the Danelaw, although this position was short-lived
3.
River Soar
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The River Soar is a major tributary of the River Trent in the English East Midlands and is the principal river of Leicestershire. The source of the river is midway between Hinckley and Lutterworth, the river then flows north through Leicester, where it is joined by the Grand Union Canal. Continuing on through the Leicestershire Soar Valley, it passes Loughborough, in the 18th century, the Soar was made navigable, initially between Loughborough and the Trent, and then through to Leicester. It was not until the early 19th century that it was linked by the Grand Union Canal to the network to the south. According to a due to William Somner the Soar river may formerly have been called the Leir, from Brittonic *Ligera or *Ligora. This theory is based on the name of Leicester being derived from the name of the river, before flowing through the centre of the city it meets the Grand Union Canal at Aylestone, where it is also joined by the River Biam. After passing over Freemens Weir, the splits and recombines with the canal. The navigable arm that runs to the east has been canalised with parallel banks and is known as ‘The Mile Straight’, beyond Blackfriars, the river splits again to form Frog Island and Abbey Park, it recombines at Belgrave where it passes beside the National Space Centre. Once out of the city the Soar passes Birstall and threads its way through the lakes of Watermead Country Park, the river then meets the once navigable River Wreake, near Cossington Mill, with another tributary the Rothley Brook, joining the river just downstream. Downstream of Stanford on Soar the river forms the county boundary between Nottinghamshire and Leicestershire, between Stanford and Normanton on Soar, the canal rejoins the river, which then continues to Zouch, passing the ‘Devils Elbow’ to reach Kegworth. Downstream of Kegworth, it meets the Kingston Brook, near the village of the name, passing Ratcliffe-on-Soar and its power station. The River Soar is rich in wildlife with thriving bird, fish, the river was once notorious for its unusual pink colour - a result of discharges from Leicesters prosperous textile industries. However the end to textile industries near the river in Leicester, industry now wanting to attempt to discharge any sewage waste into the river must now obtain an agreement from the Environment Agency. The quality of any water is determined by what is able to contaminate the river upstream, sewage works have an adverse effect on water life. 1634 Thomas Skipwith of Cotes obtained a grant from Charles I to make the river Soar portable for barges and boats,1794 The Leicester Canal was opened, making the Soar navigable for almost 40 miles. The western line was also opened- this was known as the Charnwood Forest Branch, however, most of the branch was made up of rail tracks rather than a waterway. This included a 2 1⁄2 mi uphill climb from Loughborough Basin, at the western end of the branch, rail lines travelled towards Coleorton and Swannington. A track to Cloudhill, which would have connected to lines on the Ashby Canal, was proposed
4.
ETFE
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Ethylene tetrafluoroethylene is a fluorine-based plastic. It was designed to have high resistance and strength over a wide temperature range. ETFE is a polymer and its name is poly. ETFE has a high melting temperature, excellent chemical, electrical. When burned, ETFE releases hydrofluoric acid, useful comparison tables of PTFE against FEP, PFA and ETFE can be found on DuPonts website, listing the mechanical, thermal, chemical, electrical, and vapour properties of each, side by side. ETFE is effectively the high-strength version of the three in this group, often featuring slightly diminished capacities in other fields by comparison. Combustion of ETFE occurs in the way as a number of other fluoropolymers. HF is extremely corrosive and toxic, and so caution must be exercised. ETFE film is self-cleaning and recyclable and it is prone to punctures by sharp edges and therefore mostly used for roofs. As a film for roofing it could be stretched and still be taut if some variation in size occurred, employing heat welding, tears can be repaired with a patch or multiple sheets assembled into larger panels. ETFE has a tensile strength of 42 MPa, with a working temperature range of 89 K to 423 K. ETFE resins are resistant to ultraviolet light. An accelerated weathering test produced almost no signs of film deterioration, an example of its use is as pneumatic panels to cover the outside of the football stadium Allianz Arena or the Beijing National Aquatics Centre – the worlds largest structure made of ETFE film. The panels of the Eden Project are also made from ETFE, another key use of ETFE is for the covering of electrical and fiber-optic wiring used in high-stress, low-fume-toxicity and high-reliability situations. Aircraft and spacecraft wiring are primary examples, some small cross-section wires like the wire used for the wire-wrap technique are coated with ETFE. As a dual laminate, ETFE can be bonded with FRP as a liner and used in pipes, tanks. ETFE is commonly used in the industry for tie or cable wraps and in the aviation. This is because ETFE has better mechanical toughness than PTFE, in addition, ETFE exhibits a high-energy radiation resistance and can withstand moderately high temperatures for a long period of time. Commercially deployed brand names of ETFE include Tefzel by DuPont, Fluon by Asahi Glass Company, Neoflon ETFE by Daikin, due to its high temperature resistance ETFE is also used in film mode as a mold-release film
5.
Nicholas Grimshaw
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He was President of the Royal Academy from 2004 to 2011. He is chairman of Grimshaw Architects, Grimshaw was born in Hove, East Sussex 9 October 1939. His father was an engineer, and his mother a painter and he inherited an interest in engineering. His father died when he was two and a half, and he grew up with his mother, grandmother who was also a portrait painter and he displayed an early interest in construction, his boyhood interests included Meccano, building tree houses and boats. He was educated at Wellington College, and left when he was 17 and he graduated from the AA in 1965 with an honours diploma, and having entered into a partnership with Terry Farrell, he joined the Royal Institute of British Architects two years later in 1967. He worked with Farrell for 15 years before establishing his own firm, Nicholas Grimshaw & Partners, in 1989, he won a RIBA national award for his design of the Financial Times printworks in east London. After designing Britains pavilion for the Seville Expo in 1992, he was appointed a CBE in 1993, and that same year also saw him elected a vice-chairman of the Architectural Association, a member of the Royal Academy and a member of the American Institute of Architects. Grimshaws architecture practice continues to grow, it has a profile, with offices in London, New York, Melbourne. In December 2004, Grimshaw was elected President of the Royal Academy of Arts, Grimshaw made a Knight Bachelor in 2002 New Year Honours, For services to Architecture. Grimshaw also received an Honorary Doctorate from Heriot-Watt University in 2004 Grimshaw is behind the National institute for research into aquatic habitats design, upon completion, this will become the worlds largest aquarium
6.
University of Leicester
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The University of Leicester is a public research university based in Leicester, England. The main campus is south of the city centre, adjacent to Victoria Park, the university established itself as a research-led university and was previously ranking among the top 20 universities in the United Kingdom. It was awarded University of the Year by The Times in 2008, the university is most famous for the invention of genetic fingerprinting and contributing to the discovery and identification of the remains of King Richard III. The university was founded as Leicestershire and Rutland University College in 1921, the site for the university was donated by a local textile manufacturer, Thomas Fielding Johnson, in order to create a living memorial for those who lost their lives in First World War. This is reflected in the Universitys motto Ut Vitam Habeant –so that they may have life, Students were first admitted to the college in 1921. In 1927, after it became University College, Leicester, students sat the examinations for degrees of the University of London. Two years later it merged with the Vaughan Working Mens College, in 1957 the University College was granted its Royal Charter, and has since then had the status of a university with the right to award its own degrees. Leicester University won the first ever series of University Challenge, in 1963, the main campus is a mile south of the city centre, adjacent to Victoria Park and Wyggeston and Queen Elizabeth I College. Opposite the Fielding Johnson Building are the Astley Clarke Building, home to the School of Economics, the Ken Edwards building, built in 1995, lies adjacent to the Fielding Johnson Building and is home to the School of Management. Built in 1957, the Percy Gee building is home to Leicester Universitys Students Union, the David Wilson Library was opened by Queen Elizabeth II on 4 December 2008, following an extensive refurbishment with a budget of £32 million. The university campus is home to several examples of Brutalist architecture, including the Grade II listed Engineering Building. Another prominent building on campus is the 18-storey Attenborough Tower, home to the College of Social Sciences, the Bennett building, Physics and Astronomy building, the Chemistry building and the Adrian Building lie beyond the Charles Wilson Building. Across University Road lies the Maurice Shock and Hodgkin buildings, home to Leicesters Medical School, further along University Road and on Salisbury Road and Regents Road are the Department of Education and the Fraser Noble building. On Lancaster Road there is the Attenborough Arts Centre, the Universitys arts centre, the skyline of Leicester University is punctuated by three distinctive, towering, buildings from the 1960s, the Department of Engineering, the Attenborough tower and the Charles Wilson building. The Universitys Engineering Building was the first major building by British architect James Stirling and it comprises workshops and laboratories at ground level, and a tower containing offices and lecture theatres. It was completed in 1963 and is notable for the way in which its external form reflects its internal functions, the very compact campus contains a wide range of twentieth century architecture, though the oldest building is the Fielding Johnson building. The Attenborough Tower is undergoing extensive renovation, Leicesters halls of residence are noteworthy, many of the halls date from the early 1900s and were the homes of Leicester’s wealthy industrialists. In recent years the University has disposed of some of its poorer quality property in order to invest in new facilities, the new John Foster Hall of Residence opened in October 2006
7.
Soyuz (spacecraft)
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Soyuz is a series of spacecraft designed for the Soviet space programme by the Korolyov Design Bureau in the 1960s that remains in service today. The Soyuz succeeded the Voskhod spacecraft and was built as part of the Soviet manned lunar programs. The Soyuz spacecraft is launched on a Soyuz rocket, the most frequently used, the Soyuz rocket design is based on the Vostok launcher, which in turn was based on the 8K74 or R-7A Semyorka, a Soviet intercontinental ballistic missile. All Soyuz spacecraft are launched from the Baikonur Cosmodrome in Kazakhstan, the first Soyuz flight was unmanned and started on November 28,1966. The first Soyuz mission with a crew, Soyuz 1, launched on 23 April 1967 but ended with a due to a parachute failure. Soyuz 3, launched on October 26,1968, became the programs first successful manned mission, the only other flight to suffer a fatal accident, Soyuz 11, killed its crew of three when the cabin depressurized prematurely just before reentry. These were the humans to date to have died above the Kármán line. Despite these early incidents, Soyuz is widely considered the worlds safest, most cost-effective human spaceflight vehicle, Soyuz spacecraft were used to carry cosmonauts to and from Salyut and later Mir Soviet space stations, and are now used for transport to and from the International Space Station. At least one Soyuz spacecraft is docked to ISS at all times for use as a craft in the event of an emergency. The spacecraft is intended to be replaced by the six-person Federation spacecraft, the orbital and service modules are single-use and are destroyed upon re-entry in the atmosphere. The orbital and reentry portions are habitable living space, Soyuz can carry up to three crew members and provide life support for about 30 person days. The life support system provides an atmosphere at sea level partial pressures. The atmosphere is regenerated through KO2 cylinders, which absorb most of the CO2 and water produced by the crew and regenerates the oxygen, the vehicle is protected during launch by a payload fairing, which is jettisoned along with the SAS at 2-1/2 minutes into launch. It has a docking system. The ship can be operated automatically, or by a pilot independently of ground control, inspired by the Mercury LES, Soviet designers began work on a similar system in 1962. This included developing a complex sensing system to monitor various launch vehicle parameters, the SAS could also be manually activated from the ground, but unlike American spacecraft, there was no way for the cosmonauts to trigger it themselves. Four folding stabilizers were added to improve stability during descent. Two test runs of the SAS were carried out in 1966-67, the basic design of the SAS has remained almost unchanged in 50 years of use and all Soyuz launches carry it
8.
Western world
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The Western world or the West is a term usually referring to different nations, depending on the context, most often including at least part of Europe. There are many accepted definitions about what they all have in common, the Western world is also known as the Occident. The concept of the Western part of the earth has its roots in Greco-Roman civilization in Europe, before the Cold War era, the traditional Western viewpoint identified Western Civilization with the Western Christian countries and culture. Its political usage was changed by the antagonism during the Cold War in the mid-to-late 20th Century. The term originally had a literal geographic meaning, Western culture was influenced by many older great civilizations of the ancient Near East, such as Phoenicia, Minoan Crete, Sumer, Babylonia, and also Ancient Egypt. It originated in the Mediterranean basin and its vicinity, Greece, over time, their associated empires grew first to the east and west to include the rest of Mediterranean and Black Sea coastal areas, conquering and absorbing. Later, they expanded to the north of the Mediterranean Sea to include Western, Central, numerous times, this expansion was accompanied by Christian missionaries, who attempted to proselytize Christianity. There is debate among some as to whether Latin America is in a category of its own, specifically, Western culture may imply, a Biblical Christian cultural influence in spiritual thinking, customs and either ethic or moral traditions, around the Post-Classical Era and after. European cultural influences concerning artistic, musical, folkloric, ethic and oral traditions, the concept of Western culture is generally linked to the classical definition of the Western world. In this definition, Western culture is the set of literary, scientific, political, artistic, much of this set of traditions and knowledge is collected in the Western canon. The term has come to apply to countries whose history is marked by European immigration or settlement, such as the Americas, and Oceania. The geopolitical divisions in Europe that created a concept of East and West originated in the Roman Empire, Roman Catholic Western and Central Europe, as such, maintained a distinct identity particularly as it began to redevelop during the Renaissance. Even following the Protestant Reformation, Protestant Europe continued to see itself as more tied to Roman Catholic Europe than other parts of the civilized world. Use of the term West as a cultural and geopolitical term developed over the course of the Age of Exploration as Europe spread its culture to other parts of the world. Additionally, closer contacts between the West and Asia and other parts of the world in recent times have continued to cloud the use, herodotus considered the Persian Wars of the early 5th century BC a conflict of Europa versus Asia. The terms West and East were not used by any Greek author to describe that conflict, the Great Schism and the Fourth Crusade confirmed this deviation. The Renaissance in the West emerged partly from currents within the Roman Empire, Ancient Rome was a civilization that grew from a city-state founded on the Italian Peninsula about the 9th century BC to a massive empire straddling the Mediterranean Sea. In its 12-century existence, Roman civilization shifted from a monarchy, to a republic, nonetheless, despite its great legacy, a number of factors led to the eventual decline of the Roman Empire
9.
PGM-17 Thor
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Thor was the first operational ballistic missile deployed by the U. S. Air Force. Named after the Norse god of thunder, it was deployed in the United Kingdom between 1959 and September 1963 as a ballistic missile with thermonuclear warheads. Thor was 65 feet in height and 8 feet in diameter and it was later augmented in the U. S. IRBM arsenal by the Jupiter. A large family of space launch vehicles—the Thor and Delta rockets—were derived from the Thor design. Fearful that the Soviet Union would deploy a long-range ballistic missile before the U. S. in January 1956 the USAF began developing the Thor, a 1,500 miles intermediate-range ballistic missile. The program proceeded quickly, and within three years of inception the first of 20 Royal Air Force Thor squadrons became operational in the UK, the UK deployment carried the codename Project Emily. One of the advantages of the design was that, unlike the Jupiter IRBM, the Thor could be carried by the USAFs cargo aircraft of the time, the launch facilities were not transportable, and had to be built on site. The Thor was a measure, and once the first generation of ICBMs based in the US became operational. The last of the missiles was withdrawn from operational alert in 1963, a small number of Thors, converted to Thrust Augmented Delta launchers, remained operational in the anti-satellite missile role as Program 437 until April 1975. These missiles were based on Johnston Island in the Pacific Ocean and had the ability to destroy satellites in low Earth orbit, with prior warning of an impending launch, they could destroy a Soviet spy satellite soon after orbital insertion. These missiles remain in storage, and could be reactivated, although the W-49 Mod 6 warheads were all dismantled by June 1976, development of the Thor was initiated by the USAF in 1954. The goal was a system that could deliver a nuclear warhead over a distance of 1,150 to 2,300 miles with a CEP of 2 miles. This range would allow Moscow to be hit from a site in the UK. The initial design studies were headed by Cmdr, robert Truax and Dr. Adolph K. Thiel. On November 30,1955, three companies were given one week to bid on the project, Douglas, Lockheed, and they were asked to create a management team that could pull together existing technology, skills, abilities, and techniques in an unprecedented time. On December 27,1955 Douglas was awarded the contract for the airframe. Douglas further refined the design by choosing bolted tank bulkheads and a fuel tank for improved aerodynamics. The engine was developed as a descendant of the Atlas MA-3 booster engine
10.
Beagle 2
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The Beagle 2 was a British Mars lander that was transported by the European Space Agencys 2003 Mars Express mission. It was an astrobiology mission that would have looked for past life on the shallow surface of Mars. The Beagle 2s fate remained a mystery until January 2015 when it was located intact on the surface of Mars in a series of images from NASAs Mars Reconnaissance Orbiter HiRISE camera. The images suggest that two of the four solar panels failed to deploy, blocking the spacecrafts communications antenna. The Beagle 2 is named after HMS Beagle, the used by Charles Darwin. The Beagle 2 was conceived by a group of British academics headed by Professor Colin Pillinger of the Open University, the project was designed and developed by several UK academics and companies. We hope Beagle 2 will do the thing for life on Mars. 53°N90. 50°E /11.53,90.50 was selected. The lander was expected to operate for about 180 days and a mission of up to one Martian year was thought possible. The Principal Investigator, Colin Pillinger, set up a consortium to design, in an effort to publicise the project and gain financial support, its designers sought and received the endorsement and participation of British artists. The missions call-sign was composed by the band Blur, and the test card intended for calibrating Beagle 2s cameras and spectrometers after landing was painted by Damien Hirst. The Lander Operations Control Centre was located at the National Space Centre in Leicester, from which the spacecraft was being controlled, the GTM was composed of various builds of the Beagle 2 systems, collected together to provide a full set of lander electronics. The GTM was used continuously to validate the engineering and science commands, to rehearse the landing sequence. Funding also came from the National Space Science Centre and the Wellcome Foundation, UK principal investigators for Beagle 2 came from the Open University, Leicester University and Mullard Space Science Laboratory. The budget was secret at that time but has been estimated to be between 30 and 50 million pounds, which at current exchange rates would be about 43-71 million euros or 54-89 million USD. New Scientist magazine reported a budget of 40 million pounds for Beagle 2, however, some of the work is known to have been donated or done at-cost. Robotic arm and analysers Beagle 2 has an arm known as the Payload Adjustable Workbench. The arm is 109 cm long when extended, and it can reach about 70 cm to the nearest rocks. The PAW contains a pair of cameras, a microscope, a Mössbauer spectrometer, an X-ray spectrometer, a drill for collecting rock samples
11.
Mars
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Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, after Mercury. Named after the Roman god of war, it is referred to as the Red Planet because the iron oxide prevalent on its surface gives it a reddish appearance. Mars is a planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys, deserts, and polar ice caps of Earth. The rotational period and seasonal cycles of Mars are likewise similar to those of Earth, Mars is the site of Olympus Mons, the largest volcano and second-highest known mountain in the Solar System, and of Valles Marineris, one of the largest canyons in the Solar System. The smooth Borealis basin in the northern hemisphere covers 40% of the planet, Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Mars trojan, there are ongoing investigations assessing the past habitability potential of Mars, as well as the possibility of extant life. Future astrobiology missions are planned, including the Mars 2020 and ExoMars rovers, liquid water cannot exist on the surface of Mars due to low atmospheric pressure, which is about 6⁄1000 that of the Earths, except at the lowest elevations for short periods. The two polar ice caps appear to be largely of water. The volume of ice in the south polar ice cap, if melted. On November 22,2016, NASA reported finding a large amount of ice in the Utopia Planitia region of Mars. The volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior, Mars can easily be seen from Earth with the naked eye, as can its reddish coloring. Its apparent magnitude reaches −2.91, which is surpassed only by Jupiter, Venus, the Moon, optical ground-based telescopes are typically limited to resolving features about 300 kilometers across when Earth and Mars are closest because of Earths atmosphere. Mars is approximately half the diameter of Earth with an area only slightly less than the total area of Earths dry land. Mars is less dense than Earth, having about 15% of Earths volume and 11% of Earths mass, the red-orange appearance of the Martian surface is caused by iron oxide, or rust. It can look like butterscotch, other common colors include golden, brown, tan. Like Earth, Mars has differentiated into a metallic core overlaid by less dense materials. Current models of its interior imply a core with a radius of about 1,794 ±65 kilometers, consisting primarily of iron and this iron sulfide core is thought to be twice as rich in lighter elements than Earths. The core is surrounded by a mantle that formed many of the tectonic and volcanic features on the planet
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