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Aurorae
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in polar regions of Earth, high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of brilliant lights that appear as curtains, rays, spirals, or dynamic flickers covering the entire sky. Auroras are the result of disturbances in the magnetosphere caused by the solar wind. Major disturbances result from enhancements in the speed of the solar wind from coronal holes and coronal mass ejections. These disturbances alter the trajectories of charged particles in the magnetospheric plasma. These particles, mainly electrons and protons, Electron precipitation, precipitate into the upper atmosphere (thermosphere/exosphere). The resulting ionization and excitation of atmospheric constituents emit light of varying colour and complexity. The form of the aurora, occurring within bands around both polar regions, is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aurora Australis ISS
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of brilliant lights that appear as curtains, rays, spirals, or dynamic flickers covering the entire sky. Auroras are the result of disturbances in the magnetosphere caused by the solar wind. Major disturbances result from enhancements in the speed of the solar wind from coronal holes and coronal mass ejections. These disturbances alter the trajectories of charged particles in the magnetospheric plasma. These particles, mainly electrons and protons, precipitate into the upper atmosphere (thermosphere/ exosphere). The resulting ionization and excitation of atmospheric constituents emit light of varying colour and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of accelerati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronal Holes
A coronal hole is a temporary region of relatively cool, less dense plasma (physics), plasma in the solar corona where the Sun's magnetic field extends into interplanetary space as an open field.Freedman, Roger A., and William J. Kaufmann III. "Our Star, the Sun." Universe. 8th ed. New York: W.H. Freeman, 2008. 419–420. Print. Compared to the corona's usual closed magnetic field that arches between regions of opposite magnetic polarity, the open magnetic field of a coronal hole allows solar wind to escape into space at a much quicker rate. This results in decreased temperature and density of the plasma at the site of a coronal hole, as well as an increased speed in the average solar wind measured in interplanetary space. If streams of high-speed solar wind from coronal holes encounter the Earth, they can cause major displays of aurorae. Near solar minimum, when activity such as coronal mass ejections is less frequent, such streams are the main cause of geomagnetic storms and assoc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravity, gravitationally bound system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The solar mass, vast majority (99.86%) of the system's mass is in the Sun, with most of the Jupiter mass, remaining mass contained in the planet Jupiter. The four inner Solar System, inner system planets—Mercury (planet), Mercury, Venus, Earth and Mars—are terrest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronal Mass Ejections
A coronal mass ejection (CME) is a significant release of plasma (physics), plasma and accompanying magnetic field from the Sun's Solar corona, corona into the heliosphere. CMEs are often associated with solar flares and other forms of solar activity, but a broadly accepted theoretical understanding of these relationships has not been established. If a CME enters interplanetary space, it is referred to as an interplanetary coronal mass ejection (ICME). ICMEs are capable of reaching and colliding with Earth's magnetosphere, where they can cause geomagnetic storms, aurorae, and in rare cases damage to electrical power grids. The largest recorded geomagnetic perturbation, resulting presumably from a CME, was the solar storm of 1859. Also known as the Carrington Event, it disabled parts of the at the time newly created United States Electrical telegraph, telegraph network, starting fires and shocking some telegraph operators. Near solar maximum, solar maxima, the Sun produces about ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Rome
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC), Roman Republic (509–27 BC) and Roman Empire (27 BC–476 AD) until the fall of the western empire. Ancient Rome began as an Italic settlement, traditionally dated to 753 BC, beside the River Tiber in the Italian Peninsula. The settlement grew into the city and polity of Rome, and came to control its neighbours through a combination of treaties and military strength. It eventually dominated the Italian Peninsula, assimilated the Greek culture of southern Italy ( Magna Grecia) and the Etruscan culture and acquired an Empire that took in much of Europe and the lands and peoples surrounding the Mediterranean Sea. It was among the largest empires in the ancient world, with an estimated 50 to 90 million inhabitants, roughly 20% of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galileo
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He was born in the city of Pisa, then part of the Duchy of Florence. Galileo has been called the "father" of observational astronomy, modern physics, the scientific method, and modern science. Galileo studied speed and velocity, gravity and free fall, the principle of relativity, inertia, projectile motion and also worked in applied science and technology, describing the properties of pendulums and "hydrostatic balances". He invented the thermoscope and various military compasses, and used the telescope for scientific observations of celestial objects. His contributions to observational astronomy include telescopic confirmation of the phases of Venus, observation of the four largest satellites of Jupiter, observation of Saturn's rings, and an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pole, with 0° at the Equator. Lines of constant latitude, or ''parallels'', run east–west as circles parallel to the equator. Latitude and ''longitude'' are used together as a coordinate pair to specify a location on the surface of the Earth. On its own, the term "latitude" normally refers to the ''geodetic latitude'' as defined below. Briefly, the geodetic latitude of a point is the angle formed between the vector perpendicular (or ''normal'') to the ellipsoidal surface from the point, and the plane of the equator. Background Two levels of abstraction are employed in the definitions of latitude and longitude. In the first step the physical surface is modeled by the geoid, a surface which approximates the mean sea level over the ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elias Loomis
Elias Loomis (August 7, 1811 – August 15, 1889) was an American mathematician. He served as a professor of mathematics and natural philosophy at Case Western Reserve University, Western Reserve College (now Case Western Reserve University), the New York University, University of the City of New York and Yale University. During his tenure at Western Reserve College in 1838, he established the Loomis Observatory, currently the second oldest observatory in the United States. Life and work Loomis was born in Willington, Connecticut in 1811. He graduated at Yale College in 1830, was a tutor there for three years (1833–36), and then spent the next year in scientific investigation in Paris. On his return, Loomis served as professor of mathematics and natural philosophy for eight years (1836–44) at Case Western Reserve University, Western Reserve College in Hudson, Ohio, Hudson, Ohio, now Case Western Reserve University. During his tenure, he opened up the Loomis Observatory in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomagnetic Pole
The geomagnetic poles are antipodal points where the axis of a best-fitting dipole intersects the surface of Earth. This ''theoretical'' dipole is equivalent to a powerful bar magnet at the center of Earth, and comes closer than any other point dipole model to describing the magnetic field observed at Earth's surface. In contrast, the magnetic poles of the actual Earth are not antipodal; that is, the line on which they lie does not pass through Earth's center. Owing to motion of fluid in the Earth's outer core, the actual magnetic poles are constantly moving (secular variation). However, over thousands of years, their direction averages to the Earth's rotation axis. On the order of once every half a million years, the poles reverse (i.e., north switches place with south) although the time frame of this switching can be anywhere from every 10 thousand years to every 50 million years. The poles also swing in an oval of around in diameter daily due to solar wind deflecting the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemoi
In ancient Greek religion and myth, the Anemoi (Greek: , 'Winds') were wind gods who were each ascribed a cardinal direction from which their respective winds came (see Classical compass winds), and were each associated with various seasons and weather conditions. They were the progeny of the goddess of the dawn Eos and her husband Astraeus. Etymology The earliest attestation of the word in Greek and of the worship of the winds by the Greeks, are perhaps the Mycenaean Greek word-forms , , , , i.e. 'priestess of the winds'. These words, written in Linear B, are found on the KN Fp 1 and KN Fp 13 tablets. Mythology The Anemoi are minor gods and are subject to the god Aeolus. They were sometimes represented as gusts of wind, and at other times were personified as winged men. They were also sometimes depicted as horses kept in the stables of the storm god Aeolus, who provided Odysseus with the Anemoi in the ''Odyssey''. The Spartans were reported to sacrifice a horse to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boreas (god)
In ancient Greek religion and myth, the Anemoi (Greek: , 'Winds') were wind gods who were each ascribed a cardinal direction from which their respective winds came (see Classical compass winds), and were each associated with various seasons and weather conditions. They were the progeny of the goddess of the dawn Eos and her husband Astraeus. Etymology The earliest attestation of the word in Greek and of the worship of the winds by the Greeks, are perhaps the Mycenaean Greek word-forms , , , , i.e. 'priestess of the winds'. These words, written in Linear B, are found on the KN Fp 1 and KN Fp 13 tablets. Mythology The Anemoi are minor gods and are subject to the god Aeolus. They were sometimes represented as gusts of wind, and at other times were personified as winged men. They were also sometimes depicted as horses kept in the stables of the storm god Aeolus, who provided Odysseus with the Anemoi in the ''Odyssey''. The Spartans were reported to sacrifice a horse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
