American Heritage® Dictionary of the English Language, Fourth Edition
- n. A celestial body, observed only in that part of its orbit that is relatively close to the sun, having a head consisting of a solid nucleus surrounded by a nebulous coma up to 2.4 million kilometers (1.5 million miles) in diameter and an elongated curved vapor tail arising from the coma when sufficiently close to the sun. Comets are thought to consist chiefly of ammonia, methane, carbon dioxide, and water.
Century Dictionary and Cyclopedia
- n. One of a class of celestial bodies which move about the sun in greatly elongated orbits, usually elliptical or parabolic. The typical comet, as it approaches the sun, has the appearance of a bright star-like point (the nucleus) surrounded by a mass of misty light (the coma), which is extended away from the sun into a stream of light (the tail) reaching a length of from 2° to 90°. Comets which follow a parabolic orbit appear but once, their orbit being infinite, and are called
parabolic comets; those moving in ellipses return periodically, and are called periodic comets. The fact of the periodicity of some comets was first established by Halley with reference to the comet of 1682. The paths in which they move are not, like those of the planets, all nearly in the same plane as the orbit of the earth, but are inclined to that orbit at all angles; and their motion along their paths, though generally direct, that is, in the same direction as that of the earth and the other planets, is sometimes retrograde. Some comets have no nucleus; and this is the case with every one while it is still very remote, when it appears as a mere nebulous patch. In this state it is called a telescopic comet. As it approaches the sun, the nucleus is gradually formed as a central but not sharply defined point of light; later, the tail, consisting of vaporous matter driven back by some repellent influence of the sun, often with enormous velocity, is formed; and lastly, if the comet is a bright one, a series of bright envelops rise successively from the nucleus, each extending back into the tail, and gradually disappearing. The matter of which comets are composed is so transparent that the faintest stars are seen through them without the slightest diminution of their luster. Of their physical constitution little is definitely known. The most remarkable discovery of recent times regarding them is the identity of the course of some of them with the orbit of certain showers of shooting stars. This was first demonstrated by the Italian astronomer Schiaparelli, who proved the agreement between the orbit of the great comet of 1862 and that of the star-shower seen annually about August 1st–10th. Very remarkable comets appeared in 1456, 1680, 1811, 1841, 1858 (Donati's), 1861, and 1874. They have always been objects of superstitious fear. See cut under envelop.
- n. In heraldry, same as blazing-star.
- n. One of a group of humming-birds with long forked tails: as, the Sappho comet, Cometes sappho; the Phaon comet, Cometes phaon.
- n. A game of cards, somewhat like speculation, invented and popular in the reign of Louis XV. of France.
- n. In photography, a comet-shaped defect appearing on gelatin dry plates.
- n. astronomy A celestial body consisting mainly of ice, dust and gas in a (usually very eccentric) orbit around the Sun and having a "tail" of matter blown back from it by the solar wind as it approaches the Sun.
- n. A celestial phenomenon with the appearance given by the orbiting celestial body.
GNU Webster's 1913
- n. (Astron.) A member of the solar system which usually moves in an elongated orbit, approaching very near to the sun in its perihelion, and receding to a very great distance from it at its aphelion. A comet commonly consists of three parts: the nucleus, the envelope, or coma, and the tail; but one or more of these parts is frequently wanting. See
- n. (astronomy) a relatively small extraterrestrial body consisting of a frozen mass that travels around the sun in a highly elliptical orbit
- From Old French comete (French: comète), from Latin cometes, from Ancient Greek κομήτης (komētēs, "longhaired"), referring to the tail of a comet, from κόμη (komē, "hair"). (Wiktionary)
- Middle English comete, from Old English comēta, from Late Latin, from Latin comētēs, from Greek komētēs, long-haired (star), comet, from komē, hair. (American Heritage® Dictionary of the English Language, Fourth Edition)
“With a little imagination, they might look like the heads of mourning women with long, streaming hair -- and in fact, the word comet comes from the Greek word for "hair.”
“A comet is a relatively small extraterrestrialbody witha nucleus of rock, ice, dust and gases.”
“No matter how many times you rewind the clock, the comet is still going to hit.”
“The tenuous material surrounding a comet is pushed away from the sun by radiation pressure and solar wind.”
“The tail of a comet is formed directly opposite the comet's path to or from the Sun.”
“The comet is not going to be terribly bright (in part because it has broken up into numerous fragments instead of being a single, whole comet), about magnitude 4, and has just passed through the bottom part of the constellation Lyra (right past Messier 57, the Ring Nebula; see the picture below).”
“Because these particles have come from inside a comet we know that essentially the particles haven't been heated since they became part of the comet, because the comet is made of ice," he told the BBC News website.”
“Me: That's a smart idea because once the real comet is gone it won't be back for another 4,000 years.”
“Astronomers have supposed, that if a certain comet, whose path intersected the ecliptick, had met the earth in some (I forget what) sign, it would have whirled us along with it, in it's excentrick course, into God knows what regions of heat and cold.”
“According to SKY & TELESCOPE magazine, the comet is now bright enough to be seen with the unaided eye from very dark sites free of any light pollution.”
These user-created lists contain the word ‘comet’.
A collection of words found in English that are either purely Greek or have Greek etymology.
Please add with caution and certainty. Will be regularly updated by me.
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Words from newspaper names/titles. Not the place names or titles of specific publications, just the reusable bits.
words that evoke magic, mystery, mayhem, magnificence or anything else that glimmers in the grass
Goodies pulled from a list I've compiled of most-every word having these letters in common — It's going take to take a long, long time to actually get through (and I may want to extend it lat...
Feel free to combine these in any way to create your own newspaper. Use lots of hyphens! (And yes, these are all used at real newspapers.)
All things Light
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Tulip Names II: You Know My Name
A Myriad of Irii
being words related to astronomy, stellar cartography, and the music of the spheres, including names of planets, stars and constellations
A work in progress....Birds from around the world (other than endemic to North America).
Looking for tweets for comet.