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Mark R. Showalter
Mark Robert Showalter (born December 5, 1957) is a senior research scientist at the SETI Institute. He is the discoverer of six moons and three planetary rings. He is the Principal Investigator of NASA's Planetary Data System Rings Node, a co-investigator on the Cassini–Huygens mission to Saturn, and works closely with the New Horizons mission to Pluto. Biography Showalter was born in Abington, Pennsylvania. He enjoyed playing with science-themed toys while a child, and later mowed lawns as a teenager so that he might purchase a telescope in high school. He received a Bachelor of Arts in physics and mathematics from Oberlin College in 1979. He was initially undecided about pursuing a career in astronomy after his undergraduate education, but made up his mind after seeing the images of Jupiter sent back to Earth by Voyager 2. Showalter received his MS in astronomy from Cornell University in 1982, and his PhD from Cornell in 1985. His thesis was on Jupiter's ring system, in wh ...
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Abington Township, Montgomery County, Pennsylvania
Abington Township is a Township (Pennsylvania), township in Montgomery County, Pennsylvania, United States. It is adjacent to Philadelphia's northern fringe. The population was 58,502 as of the 2020 United States census, 2020 census, making it the second most populous township in Montgomery County after Lower Merion Township, Pennsylvania, Lower Merion Township. The population density is 3603.3 per square mile (1,377/km2), making it the second most densely populated township in Montgomery County after Cheltenham Township, Montgomery County, Pennsylvania, Cheltenham Township. Abington Township is one of Montgomery County's oldest communities, dating back before 1700 and being incorporated in 1704. It is home to some of the county's oldest transportation routes, industries and churches. Many of these older business and transportation centers were the forerunners of modern Abington. Abington contains the Willow Grove Park Mall, several small businesses, and a few of Montgomery Coun ...
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Saturn
Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 times more massive. Even though Saturn is almost as big as Jupiter, Saturn has less than a third its mass. Saturn orbits the Sun at a distance of , with an orbital period of 29.45 years. Saturn's interior is thought to be composed of a rocky core, surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and an outer layer of gas. Saturn has a pale yellow hue, due to ammonia crystals in its upper atmosphere. An electrical current in the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but has a magnetic moment 580 times that of Earth because of Saturn's greater size. Saturn's magnetic field strength is about a twen ...
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Rings Of Jupiter
The rings of Jupiter are a system of faint planetary rings. The Jovian rings were the third ring system to be discovered in the Solar System, after those of Saturn and Uranus. The main ring was discovered in 1979 by the ''Voyager 1'' space probe and the system was more thoroughly investigated in the 1990s by the ''Galileo'' orbiter. The main ring has also been observed by the Hubble Space Telescope and from Earth for several years. Ground-based observation of the rings requires the largest available telescopes. The Jovian ring system is faint and consists mainly of dust. It has four main components: a thick inner torus of particles known as the "halo ring"; a relatively bright, exceptionally thin "main ring"; and two wide, thick and faint outer " gossamer rings", named for the moons of whose material they are composed: Amalthea and Thebe. The main and halo rings consist of dust ejected from the moons Metis, Adrastea and perhaps smaller, unobserved bodies as the result of hig ...
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Planetary Ring
A ring system is a disc or torus orbiting an astronomical object that is composed of solid material such as dust, meteoroids, planetoids, moonlets, or stellar objects. Ring systems are best known as planetary rings, common components of satellite systems around giant planets such as the rings of Saturn, or circumplanetary disks. But they can also be galactic rings and circumstellar discs, belts of planetoids, such as the asteroid belt or Kuiper belt, or rings of interplanetary dust, such as around the Sun at distances of Mercury, Venus, and Earth, in mean motion resonance with these planets. Evidence suggests that ring systems may also be found around other types of astronomical objects, including moons and brown dwarfs. In the Solar System, all four giant planets (Jupiter, Saturn, Uranus, and Neptune) have ring systems. Ring systems around minor planets have also been discovered via occultations. Some studies even theorize that the Earth may have had a ring system during ...
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Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined and slightly less than one-thousandth the mass of the Sun. Its diameter is 11 times that of Earth and a tenth that of the Sun. Jupiter orbits the Sun at a distance of , with an orbital period of . It is the List of brightest natural objects in the sky, third-brightest natural object in the Earth's night sky, after the Moon and Venus, and has been observed since prehistoric times. Its name derives from that of Jupiter (god), Jupiter, the chief deity of ancient Roman religion. Jupiter was the first of the Sun's planets to form, and its inward migration during the primordial phase of the Solar System affected much of the formation history of the other planets. Jupiter's atmosphere consists of 76% hydrogen and 24% helium by mass, with a denser ...
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Doctor Of Philosophy
A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of Postgraduate education, graduate study and original research. The name of the degree is most often abbreviated PhD (or, at times, as Ph.D. in North American English, North America), pronounced as three separate letters ( ). The University of Oxford uses the alternative abbreviation "DPhil". PhDs are awarded for programs across the whole breadth of academic fields. Since it is an earned research degree, those studying for a PhD are required to produce original research that expands the boundaries of knowledge, normally in the form of a Thesis, dissertation, and, in some cases, defend their work before a panel of other experts in the field. In many fields, the completion of a PhD is typically required for employment as a university professor, researcher, or scientist. Definition In the context o ...
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Master Of Science
A Master of Science (; abbreviated MS, M.S., MSc, M.Sc., SM, S.M., ScM or Sc.M.) is a master's degree. In contrast to the Master of Arts degree, the Master of Science degree is typically granted for studies in sciences, engineering and medicine and is usually for programs that are more focused on scientific and mathematical subjects; however, different universities have different conventions and may also offer the degree for fields typically considered within the humanities and social sciences. While it ultimately depends upon the specific program, earning a Master of Science degree typically includes writing a thesis. The Master of Science degree was introduced at the University of Michigan in 1858. One of the first recipients of the degree was De Volson Wood, who was conferred a Master of Science degree at the University of Michigan in 1859. Algeria Algeria follows the Bologna Process. Australia Australian universities commonly have coursework or research-based Master o ...
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Voyager 2
''Voyager 2'' is a space probe launched by NASA on August 20, 1977, as a part of the Voyager program. It was launched on a trajectory towards the gas giants (Jupiter and Saturn) and enabled further encounters with the ice giants (Uranus and Neptune). The only spacecraft to have visited either of the ice giant planets, it was the List of artificial objects leaving the Solar System, third of five spacecraft to achieve Solar escape velocity, which allowed it to leave the Solar System#Farthest regions, Solar System. Launched 16 days before its twin ''Voyager 1'', the primary mission of the spacecraft was to study the outer planets and its extended mission is to study interstellar space beyond the Sun's heliosphere. ''Voyager 2'' successfully fulfilled its primary mission of visiting the Exploration of Jupiter, Jovian system in 1979, the Exploration of Saturn, Saturnian system in 1981, Exploration of Uranus, Uranian system in 1986, and the Exploration of Neptune, Neptunian system ...
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Astronomy
Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include planets, natural satellite, moons, stars, nebulae, galaxy, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond atmosphere of Earth, Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Egyptian astronomy, Egyptians, Babylonian astronomy, Babylonians, Greek astronomy, Greeks, Indian astronomy, Indians, Chinese astronomy, Chinese, Maya civilization, M ...
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Mathematics
Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many areas of mathematics, which include number theory (the study of numbers), algebra (the study of formulas and related structures), geometry (the study of shapes and spaces that contain them), Mathematical analysis, analysis (the study of continuous changes), and set theory (presently used as a foundation for all mathematics). Mathematics involves the description and manipulation of mathematical object, abstract objects that consist of either abstraction (mathematics), abstractions from nature orin modern mathematicspurely abstract entities that are stipulated to have certain properties, called axioms. Mathematics uses pure reason to proof (mathematics), prove properties of objects, a ''proof'' consisting of a succession of applications of in ...
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Physics
Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." It is one of the most fundamental scientific disciplines. "Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physics. (...) You will come to see physics as a towering achievement of ...
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Bachelor Of Arts
A Bachelor of Arts (abbreviated B.A., BA, A.B. or AB; from the Latin ', ', or ') is the holder of a bachelor's degree awarded for an undergraduate program in the liberal arts, or, in some cases, other disciplines. A Bachelor of Arts degree course is generally completed in three or four years, depending on the country and institution. * Degree attainment typically takes five or more years in Argentina, Brazil, Chile, and Peru. * Degree attainment typically takes four years in Afghanistan, Armenia, Azerbaijan, Bangladesh, Brunei, Bulgaria, Canada (except Quebec), China, Egypt, Finland, Georgia, Ghana, Greece, Hong Kong, Indonesia, India, Iran, Iraq, Ireland, Jamaica, Japan, Kazakhstan, Kenya, Kuwait, Latvia, Lebanon, Lithuania, Malaysia, Mexico, Mongolia, Myanmar, Nepal, the Netherlands, Nigeria, Pakistan, the Philippines, Qatar, Russia, Saudi Arabia, Scotland, Serbia, Singapore, South Africa, South Korea, Spain, Sri Lanka, Taiwan, Thailand, Turkey, Ukraine, the United S ...
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