Word Finder - comets

definition

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.

definition

A celestial phenomenon with the appearance given by the orbiting celestial body.

definition

Any of several species of hummingbird found in the Andes.

We may at once put the comets out of view.

We do not know whether the comets are really indigenous to the solar system or whether they may not be merely imported into the system from the depths of space.

The solar wind has large effects on the tails of comets and even has measurable effects on the trajectories of spacecraft.

Comets are more than just a "dirty snowball" to some people.

Of his two capital errors, regarding respectively the theory of the tides and the nature of comets, the first was insidiously recommended to him by his passionate desire to find a physical confirmation of the earth's double motion; the second was adopted for the purpose of rebutting an anti-Copernican argument founded on the planetary analogies of those erratic subjects of the sun.

The most popular is, of course, Halley's Comet, but there are many more comets to choose from over the centuries.

Besides investigating other phenomena connected with a vacuum, he constructed an electrical machine which depended on the excitation of a rotating ball of sulphur; and he made successful researches in astronomy, predicting the periodicity of the return of comets.

In 1862 he published a memoir, Intorno alle strie degli spettri stellari, which indicated the feasibility of a physical classification of the stars; and on the 5th of August 1864 discovered the gaseous composition of comets by submitting to prismatic analysis the light of one then visible.

The third wants the theory of comets.

In autumn last I spent two months in calculations to no purpose for want of a good method, which made me afterwards return to the first book, and enlarge it with divers propositions, some relating to comets, others to other things, found out last winter.

Sir, I must now again beg you, not to let your resentments run so high, as to deprive us of your third book, wherein the application of your mathematical doctrine to the theory of comets and several curious experiments, which, as I guess by what you write, ought to compose it, will undoubtedly render it acceptable to those, who will call themselves Philosophers without Mathematics, which are much the greater number.

Between the orbit of Neptune and the nearest star known to us is an immense void in which no bodies are yet known to exist, except comets.

For the space of the 1 Observations of Comets, translated from the Chinese Annals by John Williams, F.S.A.

It was inferred from observations of long period comets.

Objects in our own solar system - including planets and comets - are also revealed in much greater detail by infrared astronomy.

Even at the distances from the Sun involved, a small brown dwarf among the comets could provide a habitable environment on its moons.

Yet we discover several long period comets every year.

The Oort cloud is the source of long-period comets with return times greater than 200 years.

Most of the brightest and most spectacular comets have been ones which have appeared only once and have never been seen again.

These same astrologers held that comets and other portents in the heavens were fleeting appearances of the sublunary sphere.

One advantage of the comet theory is that comets move across the starry sky.

At the great distances of the Oort Cloud, comets can be affected by the gentle gravitational tugs of nearby passing stars.

From behind the tree line two big comets soared upwards - the 12 inch shells - exploding in perfect unison.

The appearance of the Hale Bopp and Halley's comets, followed by solar and lunar eclipses, caused an upsurge in popular astronomy.

The instrumental equipment of that observatory was somewhat antiquated, his largest telescope being a small refractor of 73 lines aperture, but he selected a line of work to suit the instruments at his disposal, observing nebulae and variable stars and keeping a watch on comets and new planets.

In any case the orbits of comets are exposed to such tremendous perturbations from the planets that it is unsafe from the present orbit of a comet to conjecture what that orbit may have been in remote antiquity.

The investigation of this substance and its properties (see Radioactivity) has proceeded so far as to render it probable that the theory of the unalterability of elements, and also the hitherto accepted explanations of various celestial phenomena - the source of solar energy and the appearances of the tails of comets - may require recasting.

In Bode's Jahrbuch (1776-1780) he discusses nutation, aberration of light, Saturn's rings and comets; in the Nova acta Helvetica (1787) he has a long paper "Sur le son des corps elastiques," in Bernoulli and Hindenburg's Magazin (1787-1788) he treats of the roots of equation and of parallel lines; and in Hindenburg's Archiv (1798-1799) he writes on optics and perspective.

These differ in that comets are visible either in a telescope or to the naked eye, and seem to be either wholly or partially of a nebulous or gaseous character, while meteors are, individually at least, invisible to us except as they become incandescent by striking the atmosphere of the earth.

During the ten years 1854-1864 Donati discovered six comets, one of which, first seen on the 2nd of June 1858, bears his name (see Comet).

He maintained with full conviction to the end of his life a grossly erroneous hypothesis of the tides, early adopted from Andrea Caesalpino; the " triplicate " appearance of Saturn always remained an enigma to him; and in regarding comets as atmospheric emanations he lagged far behind Tycho Brahe.

Short period comets make hundreds to thousands of passes around the Sun spewing out gas and dust.

After maneuvering its way through comets, the StarSpeeder 3000 encounters a Star Destroyer ship, where a battle ensues.

The most famous comet is, of course, Halley's Comet, but there are other comets like Holme's and Hale-Bopp.

Ancient civilizations were not immune to the wonder of the comets over head, add have seen the appearance of them as an omen or sign that the end of the world is upon us; a harbinger of doom.

If we take in to account all of the bad omens and wives tales surrounding comets, these myths and fears can also give way as a means to signify change in someone's life.

Even if the comets be indigenous to the system, they may, as many suppose, be merely ejections from the sun.

On these grounds we discuss the nebular theory without much reference to comets.

By this means she detected in 1783 three remarkable nebulae, and during the eleven years 1786-1797 eight comets, five of them with unquestioned priority.

The Memoirs of the Berlin Academy from 1761 to 1784 contain many of his papers, which treat of such subjects as resistance of fluids, magnetism, comets, probabilities, the problem of three bodies, meteorology, &c. In the Acta Helvetica (1752-1760) and in the Nova acta erudita (1763-1769) several of his contributions appear.

In the re- establishment of the field comets and in other directions a return was made to the republican forms of administration, and on the education question an agreement satisfactory to both the British and Dutch-speaking communities was reached.

The meteors, whatever their dimensions, must have motions around the sun in obedience to the law of gravitation in the same manner as planets and comets - that is, in conic sections of which the sun is always at one focus.

The great variety in the apparent motions of meteors proves that they are not directed from the plane of the ecliptic; hence their orbits are not like the orbits of planets and short-period comets, which are little inclined, but like the orbits of parabolic comets, which often have great inclinations.

Apart from the instances alluded to there seem few coincidences between the orbital elements of comets and meteors.

But there are really few comets which pass sufficiently near the earth to give rise to a meteoric shower.

Of 80 comets seen during the 20 years ending 1893, Professor Herschel found that only two, viz.

A fourth class of bodies, the constitution of which is still in some doubt, comprises comets and meteors.

He intended to follow it up with similar treatises on Mars, Jupiter, sun, moon, comets and meteors, stars, and nebulae, and had in fact commenced a monograph on Mars, when the failure of a New Zealand bank deprived him of an independence which would have enabled him to carry out his scheme without anxiety as to its commercial success or failure.

He paid special attention to comets, and that of 1815 (period seventy-four years) bears his name in commemoration of its detection by him.

His observations on the three comets of 1618 were published in De Cometis, contemporaneously with De Harmonice Mundi (Augsburg, 1619), of which the first lineaments had been traced twenty years previously at Gratz.