ignimbrite
ignimbrite A poorly sorted,
pyroclastic rock body formed by deposition from a pumiceous pyroclastic flow. The passage of one pyroclastic flow deposits one ignimbrite flow unit with a number of layers directly related to the components of the flow. Ignimbrite flow units deposited by the passage of successive flows can accumulate into a loosely consolidated, composite sheet. Where the rock-body temperature and the accumulating overburden load are both sufficiently high, sintering and flattening of
groundmass shards and
pumice clasts can occur in the lower part of the body, producing a welded zone within the ignimbrite body which is then characterized by the development of a
eutaxitic texture. Hot gases escaping through the ignimbrite deposit can precipitate minerals between the loosely packed shards and pumice in the upper parts of the flow, creating a lithified
sillar horizon in which the glass of the pumice and shards is devitrified. Ignimbrites are found on all scales, from a few hundred metres to more than 100 km long, and from one metre to tens of metres thick. The geometry of the ignimbrite sheet is descried using the aspect ratio. See
HIGH-ASPECT-RATIO IGNIMBRITE; and
LOW-ASPECT-RATIO IGNIMBRITE.
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California Inventor Develops Stars Positions Conversion Process
News Wire article from: US Fed News Service, Including US State News; 8/4/2006; 458 words
; ...unique celestial mapping systems, processes and star...objects from equatorial coordinates of right ascension and declination to ecliptic coordinates of celestial...stars and planets in ecliptic coordinates. The invention...or data array, in ecliptic coordinates by ...
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The intrinsic distribution and selection bias of long-period cometary orbits.
Magazine article from: Journal of the American Statistical Association; 9/1/2003; ; 700+ words
; ...formed within the solar system and were subsequently...the (heliocentric) ecliptic coordinate system, which is indicated...intersection of the ecliptic plane (the plane of...first and lies in the ecliptic plane. The third axis...
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Researchers from Adam Mickiewicz University publish new studies and findings in the area of astrophysics.(Report)
Newspaper article from: Physics Week; 8/25/2009; 700+ words
; ...a synchronous binary system with an orbital period...first modelling of the system. For simplicity we...Poles of the orbit in ecliptic coordinates are lambda = 119...period of the Lundia system obtained from modelling...
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California Inventor Develops Zodiac Sign Horoscope Mapping Device
News Wire article from: US Fed News Service, Including US State News; 5/5/2008; 512 words
; ...device, locating the coordinate positions of the twelve...The device divides the ecliptic coordinate sphere into...dependent device divides the ecliptic coordinate sphere into twelve non...automated information message system.
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Conjunction functions.(SCOPE on the skies)
Magazine article from: Science Scope; 4/1/2007; ; 700+ words
; ...arrangements of solar system objects, while occultations...near the plane of the ecliptic that most solar system...Using the Moon's coordinate positions in Figure...maps that show the ecliptic path. The coordinate position and Moon phase...
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An Islamic Response to Greek Astronomy: Kitab Tad dil Hay at al-Aflak of Sadr al-Sharia.
Magazine article from: The Journal of the American Oriental Society; 4/1/1997; ; 700+ words
; ...northwestern Iran, undertook to reform the system. With varying success, they attempted to substitute...the fixed stars, and defines the equatorial, ecliptic, and horizon coordinate systems. Chapters 4, 5, 6, and 7 deal with the mechanisms...
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Planets in Motion.
Magazine article from: Science Scope; 9/1/2005; ; 700+ words
; ...chart section showing ecliptic and sky equator and...planets in our solar system revolve around the...path is called the ecliptic and all planets, except...chart with celestial coordinates. (See Resources for...application of a familiar coordinate system to something...using the ...
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Tracking planets around the Sun.(SCOPE ON THE SKIES)(Report)
Magazine article from: Science Scope; 3/1/2008; ; 700+ words
; ...series about the solar system began last September...celestial coordinate systems. In earlier columns, the celestial coordinate system of hour circles of...motion relative to the ecliptic, the apparent path...longitude This is a coordinate system where planets...print ...
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NASA's Open House
Newspaper article from: The Washington Post; 6/5/2001; ; 700+ words
; ...Comberiate, the center's spacecraft systems manager, explains "What We Are Learning...s Earth Science Enterprise, and it coordinates NASA research of Earth's environment...east-southeast, cruising along the ecliptic and snuggled between the constellations...
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Analemma, the ancient sketch of fictitious sunpath geometry--sun, time and history of mathematics.
Magazine article from: Architectural Science Review; 6/1/2004; ; 700+ words
; ...as an instrument for measuring solar coordinates on a fictitious sky dome is examined...Julius Caesar in 46 BC, following the system used in Egypt since 238 BC, introduced...sunpaths with his gnomon and defined the ecliptic at about 570 BC. It is open to question...
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ecliptic coordinates
Book article from: A Dictionary of Astronomy
ecliptic coordinates A system of coordinates that specifies the position of an object in the Solar System relative to the plane of the Earth's orbit, the ecliptic. Ecliptic coordinates of objects as they would be seen from the centre...
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ecliptic coordinate system
Book article from: The Columbia Encyclopedia, Sixth Edition
ecliptic coordinate system an astronomical coordinate system...the principal coordinate axis is the ecliptic , the apparent path of the sun through the heavens. The ecliptic poles are the two points at which...
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ecliptic
Book article from: The Columbia Encyclopedia, Sixth Edition
...annual journey through the heavens with the ecliptic as its path. The ecliptic is the principal axis in the ecliptic coordinate system . The two points at which the ecliptic crosses the celestial equator are the equinoxes . The obliquity of the...
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Celestial coordinates
Encyclopedia entry from: The Gale Encyclopedia of Science
Celestial coordinates In astronomy, celestial coordinate systems locate...celestial coordinate systems: horizontal, equatorial, ecliptic, and galactic. Horizontal coordinates (also called...the solar system to the center...
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celestial coordinates
Book article from: A Dictionary of Astronomy
celestial coordinates Any system for locating the...sphere. Various systems are defined, according...objects in the Solar System, give the position...or topocentric. Ecliptic coordinates take the ecliptic as their reference...
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