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Definition: Telescope |
TelescopeNoun1. A magnifier of images of distant objects. Verb1. Crush together, as of cars in a collision. 2. Make smaller or shorter; "the novel was telescoped into a short play". Source: WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. |
Date "telescope" was first used in popular English literature: sometime before 1550. (references) |
Note: Telescope \Tel"e*scope\, adjective. [imperfect & past participle. Telescoped; Telescoping.]. (references) |
| Domain | Definition |
Satire | TELESCOPE, n. A device having a relation to the eye similar to that of the telephone to the ear, enabling distant objects to plague us with a multitude of needless details. Luckily it is unprovided with a bell summoning us to the sacrifice. Source: Devil's Dictionary. |
Dream Interpretation | To dream of a telescope, portends unfavorable seasons for love and domestic affairs, and business will be changeable and uncertain. To look at planets and stars through one, portends for you journeys which will afford you much pleasure, but later cause you much financial loss. To see a broken telescope, or one not in use, signifies that matters will go out of the ordinary with you, and trouble may be expected. Source: Ten Thousand Dreams Interpreted .... |
Source: compiled by the editor from various references; see credits. | |
(From Wikipedia, the free Encyclopedia)
The credit for the discovery of the telescope has been a subject of discussion. Thus, because Democritus announced that the Milky Way is composed of vast multitudes of stars, it has been maintained by some that he could only have been led to form such an opinion from actual examination with a telescope. Other passages from the Greek and Latin authors have similarly been cited to prove that the telescope was known to the ancients. But we are no more warranted in drawing such a conclusion without any evidence other than casual remarks, however sagacious, than we should be justified in stating that Seneca was in possession of the theories of Newton because he predicted that comets would one day be found to revolve in periodic orbits.
Refracting telescopes
It is quite certain that prior to 1600 the telescope was unknown, except possibly to individuals who failed to see its practical importance, and who confined its use to curious practices or to demonstrations of "natural magic." The practical discovery of the instrument was certainly made in the Netherlands about 1608, but the credit of the original invention has been claimed on behalf of three individuals, Hans Lippershey and Zacharias Jansen, spectacle-makers in Middelburg, and James Metius of Alkmaar.The original Dutch telescopes were composed of a convex and a concave lens, and telescopes so constructed do not invert the image. Telescopes seem to have been made in the Netherlands in considerable numbers soon after the date of their invention, and rapidly found their way over Europe.
Galileo, happening to be in Venice in about the month of May 1609, heard that a Belgian had invented a perspective instrument by means of which distant objects appeared nearer and larger, and that he discovered its construction by considering the effects of refraction. Galileo states that he solved the problem of the construction of a telescope the first night after his return to Padua from Venice, and made his first telescope the next day by fitting a convex lens in one extremity of a leaden tube and a concave lens in the other one. A few days afterwards, having succeeded in making a better telescope than the first, he took it to Venice, where he communicated the details of his invention to the public, and presented the instrument itself to the doge Leonardo Donato, sitting in full council. The senate, in return, settled him for life in his lectureship at Padua and doubled his salary. Galileo may thus claim to have invented the telescope independently, but not till he had heard that others had done so.
Galileo devoted his time to improving and perfecting the telescope, and soon succeeded in producing telescopes of greatly increased power. His first telescope magnified three diameters; but he soon made instruments which magnified eight diameters, and finally one that magnified thirty-three diameters. With this last instrument he discovered in 1610 the satellites of Jupiter, and soon, afterwards the spots on the sun, the phases of Venus, and the hills and valleys on the moon. He demonstrated the revolution of the satellites of Jupiter around the planet, and gave rough predictions of their configurations, proved the rotation of the sun on its axis, established the general truth of the Copernican system as compared with that of Ptolemy, and fairly routed the fanciful dogmas of the philosophers. These brilliant achievements, together with the immense improvement of the instrument under the hands of Galileo, overshadowed in a great degree the credit due to the original discoverer, and led to the universal adoption of the name of the Galilean telescope for the form of the instrument invented by Lippershey.
Johannes Kepler first explained the theory and some of the practical advantages of a telescope constructed of two convex lenses in his Catopirics (1611). The first person who actually constructed a telescope of this form was the Jesuit Christoph Schemer, who gives a description of it in his Rosa Ursina (1630).
William Gascoigne was the first who practically appreciated the chief advantages of the form of telescope suggested by Kepler, viz., the visibility of the image of a distant object simultaneously with that of a small material object placed in the common focus of the two lenses. This led to his invention of the micrometer and his application of telescopic sights to astronomical instruments of precision. But it was not till about the middle of the 17th century that Kepler's telescope came into general use, and then, not so much because of the advantages pointed out by Gascoigne, but because its field of view was much larger than in the Galilean telescope.
The first powerful telescopes of this construction were made by Christiaan Huygens, after much labour, in which he was assisted by his brother. With one of these, of 12-ft. focal length, he discovered the brightest of Saturn's satellites (Titan) in 1655, and in 1659 he published his Systema Saturnium, in which was given for the first time a true explanation of Saturn's ring, founded on observations made with the same instrument. The sharpness of image in Kepler's telescope is very inferior to that of the Galilean instrument, so that when a high magnifying power is required it becomes essential to increase the focal length.
Giovanni Cassini discovered Saturn's fifth satellite (Rhea) In 1672 with a telescope of 35 ft., and the third and fourth satellites in 1684 with telescopes made by Campani of 100- and 136-foot focal length. Christian Huygens states that he and his brother made object-glasses of 170 and 210 ft. focal length, and he presented one of 123 feet to the Royal Society of London. Adrien Auzout (died in 1691) and others are said to have made telescopes of from 300 to 600 ft. locus, but it does not appear that they were ever able to use them in practical observations. James Bradley, on December 27, 1722, actually measured the diameter of Venus with a telescope whose object glass had a focal length of 212 ft. In these very long telescopes no tube was employed, and they were consequently termed aerial telescopes. Huygens contrived some ingenious arrangements for directing such telescopes towards any object visible in the heavens-the focal adjustment and centring of the eyepiece being preserved by a braced rod connecting the object glass and eyepiece. Other contrivances for the same purpose are described by Philippe de la Hire (Mém. de l'Acad., 1715) and by Nicolaus Hartsoeker (Miscel. Berol., 1710, vol. i. p. 261). Telescopes of such great length were naturally difficult to use, and must have taxed to the utmost the skill and patience of the observers. One cannot but pay a passing tribute of admiration to the men who, with such troublesome tools, achieved such results.
Reflecting telescopes
Until Newton's discovery of the different refrangibility of light of different colours, it was generally supposed that object-glasses of telescopes were subject to no other errors than those which arose from the spherical figure of their surfaces, and the efforts of opticians were chiefly directed to the construction of lenses of other forms of curvature. James Gregory, in his Optica Promota (1663), discusses the forms of images and objects produced by lenses and mirrors, and shows that when the surfaces of the lenses or mirrors are portions of spheres the images are curves concave towards the objective, but if the curves of the surfaces are conic sections, the spherical aberration is corrected. He was well aware of the failures of all attempts to perfect telescopes by employing lenses of various forms of curvature, and accordingly proposed the form of reflecting telescope which bears his name: the Gregorian telescope. But Gregory, according to his own confession, had no practical skill; he could find no optician capable of realizing his ideas, and after some fruitless attempts was obliged to abandon all hope of bringing his telescope into practical use. Newton was the first to construct a reflecting telescope.'''When in 1666 he made his discovery of the different refrangibility of light of different colours, he soon perceived that the faults of the refracting telescope were due much more to this cause than to the spherical figure of the lenses. He overhastily concluded from some rough experiments (Optics, bk. i. pt. ii. prop. 3) that all refracting substances diverged the prismatic colours in a constant proportion to their mean refraction; and he drew the natural conclusion that refraction could not be produced without colour, and therefore that no improvement could he expected from the refracting telescope (Treatise on Optics, p. 112). But, having ascertained by experiment that for all colours of light the angle of incidence is equal to the angle of reflexion, he turned his attention to the construction of reflecting telescopes. After much experiment he selected an alloy of tin and copper as the most suitable material for his specula, and he devised means for griding and polishing them. He did not attempt the formation of a parabolic figure on account of the probable mechanical difficulties, and he had besides satisfied himself that the chromatic and not the spherical aberration formed the chief faults of previous telescopes. Newton's first telescope so far realized his expectations that he could see with its aid the satellitess of Jupiter and the horns of Venus. Encouraged by this success, he made a second telescope of 6k-in. focal length, with a magnifying power of 38 diameters, which he presented to the Royal Society of London in December 1671. A third form of reflecting telescope was devised in 1672 by Cassegrain (Journal des Savants, 1672). No further practical advance appears to have been made in the design or construction of the instrument till the year 1723, when John Hadley (best known as the inventor of the sextant) presented to the Royal Society a reflecting telescope of the Newtonian construction, with a metallic speculum of 6-in. aperture and 623/4-in, focal length, having eyepieces magnifying up to 230 diameters. The instrument was examined by Pound and Bradley, the former of whom reported upon it in Phil, Trans., 1723, No. 378, p. 382. After remarking that Newton's telescope had lain neglected these fifty years, they stated that Hadley had sufficiently shown that this noble invention does not consist in bare theory. They compared its performance with that of the object-glass of 123-ft. focal length presented to the Royal Society by Huygens, and found that Hadley's reflector will bear such a charge as to make it magnify the object as many times as the latter with its due charge, and that it represents objects as distinct, though not altogether so clear and bright.
Not withstanding this difference in the brightness of the objects, we were able with this reflecting telescope to see whatever we have hitherto discovered with the Huygenian, particularly the transits of Jupiter's satellites and their shadows over his disk, the black list in Saturn's ring, and the edge of his shadow cast on his ring. We have also seen with it several times the five satellites of Saturn, in viewing of which this telescope had the advantage of the Huygenian at the time when we compared them; for, being in summer, and the Huygenian telescope being managed without a tube, the twilight prevented us from seeing in this some of these small objects which at the same time we could discern with the reflecting telescope.
Bradley and Molyneux, having been instructed by Hadley in his methods of polishing specula, succeeded in producing some telescopes of considerable power, one of which had a focal length of 8 ft.; and, Molyneux having communicated these methods to Scarlet and Hearn, two London opticians, the manufacture of telescopes as a matter of business was commenced by them (Smith's Opticks, bk, iii. ch. I). But it was reserved for James Short of Edinburgh to give practical effect to Gregory's original idea. Born at Edinburgh in 1710 and originally educated for the church, Short attracted the attention of Maclaurin, professor of mathematics at the university, who permitted him about 1732 to make use of his rooms in the college buildings for experiments in the construction of telescopes. In Short's first telescopes the specula were of glass, as suggested by Gregory, but he afterwards used metallic specula only, and succeeded in giving to them true parabolic and elliptic figures. Short then adopted telescope-making as his profession, which he practised first in Edinburgh and afterwards in London. All Short's telescopes were of the Gregorian form, and some of them retain even to the present day their original high polish and sharp definition. Short died in London in 1768, having realized a considerable fortune by the exercise of his profession.
Achromatic Telescope
The historical sequence of events now brings us to the discovery of the achromatic telescope. The first person who succeeded in making achromatic refracting telescopes seems to have been Chester Moor Hall, a gentleman of Essex. He argued that the different humours of the human eye so refract rays of light as to produce an image on the retina which is free from colour, and he reasonably argued that it might be possible to produce a like result by combining lenses composed of different refracting media. After devoting some time to the inquiry he found that by combining lenses formed of different kinds of glass the effect of the unequal refrangibility of light was corrected, and in 1733 he succeeded in constructing telescopes which exhibited objects free from colour. One of these instruments of only 20-in. focal length had an aperture of 21/2 in, Hall was a man of independent means, and seems to have been careless of fame; at least he took no trouble to communicate his invention to the world. At a trial in Westminster Hall about the patent rights granted to John Dollond (Watkin v. Dollond), 1 Hall was admitted to be the first inventor of the achromatic telescope; but it was ruled by Lord Mansfield that it was not the person who locked his invention in his scrutoire that ought to profit for such invention, but he who brought it forth for the benefit of mankind. 3 In 1747 Leonhard Euler communicated to the Berlin Academy of Sciences a memoir in which he endeavoured to prove the possibility of correcting both the chromatic and the spherical aberration of an object-glass. Like Gregory and Hall, he argued that, since the various humours of the human eye were so combined as to produce a perfect image, it should be possible by suitable combinations of lenses of different refracting media to construct a perfect object-glass. Adopting a hypothetical law of the dispersion of differently coloured rays of light, he proved analytically the possibility of constructing an achromatic object-glass composed of lenses of glass and water. But all his efforts to produce an actual objectglass of this construction were fruitless-a failure which he attributed solely to the difficulty of procuring lenses worked precisely to the requisite curves (Mem. Acad. Berlin, 1753). Dollond admitted the accuracy of Euler's analysis, but disputed his hypothesis on the grounds that it was purely a theoretical assumption, that the theory was opposed to the results of Newton's experiments on the refrangibility of light, and that it was impossible to determine a physical law from analytical reasoning alone (Phil. Trans., 1753, p. 289). In 1754 Euler communicated to the Berlin Academy a further memoir, in which, starting from the hypothesis that light consists of vibrations excited in an elastic fluid by luminous bodies, and that the difference of colour of light is due to the greater or less frequency of these vibrations in a given time, he deduced his previous results. He did not doubt the accuracy of Newton's experiments quoted by Dollond, because he asserted that the difference between the law deduced by Newton and that which he assumed would not be rendered sensible by such an experiment,4 Dollond did not reply to this memoir, but soon afterwards he received an abstract of a memoir by Samuel Klingenstierna, the Swedish mathematician and astronomer, which led him to doubt the accuracy of the results deduced by Newton on the dispersion of refracted light. Klingenstierna showed from purely geometrical considerations, fully appreciated by Dollond, that the results of Newton's experiments could not be brought into harmony with other universally accepted facts of refraction. Like a practical man, Dollond at once put his doubts to the test of experiment, confirmed the conclusions of Klingenstierna, discovered a difference far beyond his hopes in the refractive qualities of different kinds of glass with respect to their divergency of colours, and was thus rapidly led to the construction of object-glasses in which first the chromatic and afterwards the spherical aberration were corrected (Phil. Trans., 1758, p. 733).
We have thus followed somewhat minutely the history of the gradual process by which Dollond arrived independently at his invention of the refracting telescope, because it has been asserted that he borrowed the idea from others. Montucla, given for his invention, was the dead, and his son brought an action for infringing the patent against Chainpness, There is no report of the case, but the facts are referred to in the reports of subsequent cases, It appears that workmen who had been employed by Mr Moor Hall were examined, and proved that they had made achromatic object-glasses as early as 1733. Dollond's patent was not set aside, though the evidence with regard to the prior manufacture was accepted by Lord Mansfield, who tried the case, as having been satisfactorily proved.
It is clearly established that Hall was the first inventor of the achromatic telescope; but Dollond did not borrow the invention from Hall without acknowledgment, in the manner suggested by Lalande. His discovery was beyond question an independent one. The whole history of his researches proves how fully he was aware of the conditions necessary for the attainment of achromatism in refracting telescopes, and he may be well excused if he so long placed implicit reliance on the accuracy of experiments made by so illustrious a philosopher as Newton. His writings sufficiently show that but for this confidence he would have arrived sooner at a discovery for which his mind was fully prepared. It is, besides, impossible to read Dollond's memoir (Phil. Trans., 1758, p. 733) without being impressed with the fact that it is a truthful account, not only of the successive steps by which he independently arrived at his discovery, but also of the logical processes by which these steps were successively suggested to his mind.
The triple object-glass, consisting of a combination of two convex lenses of crown glass with a concave flint lens between them, was introduced in 1765 by Peter, son of, John Dollond, and many excellent telescopes of this kind were made by him.
The limits of this article do not permit a further detailed historical statement of the various steps by which the powers of the telescope were developed. Indeed, in its practical form the principle of the instrument has remained unchanged from the time of the Dollonds to the present day; and the history of its development may be summed up as consisting not in new optical discoveries but in utilizing new appliances for figuring and polishing, improved material for specula and lenses, more refined means of testing, and more perfect and convenient methods of mounting.
About the year 1774 William Herschel, then a teacher of music in Bath, began to occupy his leisure hours with the construction of specula, and finally devoted himself entirely to their construction and use. In 1778 he had selected the chef-d'oeuvre of some 400 specula which he made for the celebrated instrument of 7-ft. focal length with which his early brilliant astronomical discoveries were made. In 1783 he completed his reflector of 184 in. aperture and 20-ft. focus, and in 1789 his great reflector of 4-ft. aperture and 40-ft. focal length. The fame of these instruments was rapidly spread by the brilliant discoveries which their maker's genius and perseverance accomplished by their aid. The reflecting telescope became the only available tool of the astronomer when great light grasp was requisite, as the difficulty of procuring disks of glass (especially of flint glass) of suitable purity and homogeneity limited the dimensions of the achromatic telescope. It was in vain that the French Academy of Sciences offered prizes for perfect disks of optical flint glass. Some of the best chemists and most enterprising glass-manufacturers exerted their utmost efforts without succeeding in producing perfect disks of more than 31/2 in. in diameter. All the large disks were crossed by striae, or were otherwise deficient in the necessary homogeneity and purity.
From 1911 EB, further rework required
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "History of telescopes."
(From Wikipedia, the free Encyclopedia)
A telescope is perhaps the most important astronomical tool; such technology gathers (and focuses) electromagnetic radiation. Telescopes increase the apparent angular size of objects, as well as their apparent brightness. Galileo is credited with being the first to use a telescope for astronomical purposes. Telescopes used for non-astronomical purposes are often referred to as transits, spotting scopes, monoculars, binoculars, camera lenses, or spyglasses.
The word "telescope" usually refers to optical telescopes, but there are telescopes for most of the spectrum of electromagnetic radiation.
Radio telescopes are focused radio antennas, usually shaped like large dishes. The dish is sometimes constructed of a conductive wire mesh whose openings are smaller than a wavelength. Radio telescopes are often operated in pairs, or larger groups to synthesize large "virtual" apertures that are similar in size to the separation between the telescopes: see aperture synthesis. The current record is nearly the width of the Earth. Aperture synthesis is now also being applied to optical telescopes.
X-ray and gamma-ray telescopes have a problem because the rays go through most metals and glasses. They use ring-shaped "glancing" mirrors made of heavy metals, that reflect the rays just a few degrees. The mirrors are usually a section of a rotated parabola.
Telescope mountings
The simpliest telescope mounting is an altazimuth mount. It is similar to that of a surveying transit. A fork rotates in azimuth, and bearings on the tips of the fork allow the telescope to vary in altitude.
The major problem with using an altazimuth for astronomy is that both axes must be continuously adjusted to compensate for the Earth's rotation. Even if this is done, by computer control, the image rotates at a rate that varies depending on the angle of the star from the celestial pole. The last effect especially makes an altazimuth mount impractical for long-exposure photography with small telescopes.
The preferred solution for many small telescopes is to tip the altazimuth so that the azimuth axis is parallel with the axis of the Earth's rotation, this is known as equatorial mount.
Very large telescopes typically use a computer-controlled altazimuth mount, and for long exposures, they have (usually computer-controlled) variable-rate rotating erector prisms at the focus.
Research Telescopes
Most large research telescopes can operate as either a cassegrainian (longer focal length, and a narrower field with higher magnification) or newtonian (brighter field). They have a pierced primary, a newtonian focus, and a spider to mount a variety of replaceable secondaries.
A new era of telescope making was inaugurated by the MMT, a synthetic aperture composed of six segments synthesizing a mirror of 4.5 meters diameter. Its example was followed by the Keck telescopes, a synthetic-aperture 10 meter telescope.
The current generation of telescopes being constructed have a primary mirror of between 6 and 8 meters in diameter (for ground-based telescopes). In this generation of telescopes, the mirror is usually very thin, and is kept in an optimal shape by an array of actuators (see active optics). This technology has driven new designs for future telescopes with diameters of 30, 50 and even 100 meters.
Initially the detector used in telescopes was the human eye. Later, the sensitized photographic plate took its place, and the spectrograph was introduced, allowing the gathering of spectral information. After the photographic plate, successive generations of electronic detectors, such as CCDs, have been perfected, each with more sensitivity and resolution.
Current research telescopes have several instruments to choose from: imagers, of different spectral responses; spectrographs, useful in different regions of the spectrum; polarimeters, that detect light polarization, etc.
In recent years, some technologies to overcome the bad effect of atmosphere on ground-based telescopes were developed, with good results. See tip-tilt mirror and adaptive optics.
The phenomenon of optical diffraction sets a limit to the resolution and image quality that a telescope can achieve, which is the effective area of the Airy disc, which limits how close we may place two such discs. This absolute limit is called Sparrow's resolution limit. This limit depends on the wavelength of the studied light (so that the limit for red light comes much earlier than the limit for blue light) and on the diameter of the telescope mirror. This means that a telescope with a certain mirror diameter can resolve up to a certain limit at a certain wavelength, so if you want more resolution at that very wavelength, you have to build a wider mirror.
Famous Telescopes
- The Hubble space telescope is in orbit outside of the Earth's atmosphere to allow for observations not distorted by refraction, in this way they can be diffraction limited, and used for coverage in the ultraviolet (UV) and infrared.
- The Very Large Telescope (VLT) is currently (2002) the record holder in size, with four telescopes each 8 meters in diameter. The four telescopes, belonging to ESO and located in the Atacama desert in Chile, can operate independently or together.
- There are many plans for even larger telescopes, one of them is the Overwhelmingly Large Telescope or OWL, which is intended to have a single aperture of 100 meters in diameter.
- The 200 inch Hale telescope at Mt. Palomar is a conventional research telescope that was the largest for many years. It has a single borosilicate (Pyrex (TM)) mirror that was famously difficult to construct. The mounting is also unique, an equatorial mount that is not a fork, yet permits the telescope to image near the north celestial pole.
- The 100 inch Mt. Wilson telescope was used by Edwin Hubble to discover galaxies, and the redshift. It is now part of a synthetic aperture array with several other Mt. Wilson telescopes, and is still useful for advanced research.
- The 0.91m Yerkes Telescope (in Wisconsin) is the largest aimable refractor in use.
- The largest refractor ever constructed was French. It was on display at the 1900 Paris Exposition. Its lens was stationary, prefigured so as to sag into the correct shape. The telescope was aimed by by the aid of a Foucault sidérostat, which is a movable plane mirror of diameter 6.56 feet, mounted in a large cast-iron frame. The horizontal tube was 197 feet long and the objective had 4.1 feet in diameter. It was a failure.
See also:
- Amateur telescope making
- History of telescopes
- Timeline of telescopes, observatories, and observing technology
- List of telescope types
- List of largest optical refracting telescopes
- List of largest optical reflecting telescopes
- Reflector telescope
- Refracting telescope
External links
- http://www.eso.org/projects/owl/
- The Resolution of a Telescope
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Telescope."
| The following table is compiled from various sources, across various languages. When English abbreviations or acronyms come from a non-English source, this is noted. | |||
| Entry | Source | Expression | Field |
| TET | English | Telescope and electron telescope | N/A |
Source: compiled by the editor, based on several corpora (additional references). | |||
Synonym: TelescopeSynonym: scope (n). (additional references) |
| Context | Synonyms within Context (source: adapted from Roget's Thesaurus). |
Impulse | Come into a collision, enter into collision; collide; sideswipe; foul; fall foul of, run foul of; telescope. |
| Source: adapted from Roget's Thesaurus. | |
| Domain | Usage | |
Screenplays | Dr. Arroway will be spending her precious telescope time listening for uh listening for (Contact; writing credit: Carl Sagan;) But you're not even looking through the telescope. (Down with Love; writing credit: Eve Ahlert; Dennis Drake) I'd need a telescope to see that (Fawlty Towers; writing credit: John Cleese; Connie Booth) What wonderful intstruments! The Ear Scope! The Teletalker, that knows everything! The Cosmic Telescope! The Master Eye (Santa Claus; writing credit: René Cardona; Adolfo Torres Portillo) You didn't think the Colonel had a telescope on his roof just to look at the neighbors did you (Stargate SG-1; writing credit: Robert C. Cooper; Brad Wright) | |
Clever | We often see further through a tear than through a telescope. (references; author: unknown) | |
Movie/TV Titles | Telescope (1963) The Magnetic Telescope (1942) As Seen Through a Telescope (1900) The Telescope (2002) | |
Source: compiled by the editor from various references; see credits. | ||
| Domain | Title | ||
Books | |||
Periodicals |
| ||
Theater & Movies | |||
Music |
| ||
High Tech |
| ||
Source: compiled by the editor from various references; see credits. | |||
| Thumbnail | Description & Credit | Thumbnail | Description & Credit |
 | Fourier Telescope. Credit: NASA. |  | Hubble Space Telescope and Earth Limb. Credit: NASA. |
 | Astronomer John S. Mulchaey, of the Space Telescope Science Institute (STSCI) and fellow ... Credit: NASA. |  | This visible-light picture, taken by the Hubble telescope, reveals an intergalactic ... Credit: NASA. |
 | Radar images of the asteroid Toutatis obtained with NASA's 70 m radio telescope at Goldstone. Credit: NASA. |  | Montage of images of the asteroid Vesta taken by the Hubble Space Telescope using the Wide-Field Planetary Camera 2. Credit: NASA. |
 | Zenith telescope at the Ukiah Latitude Observatory Showing latitude levels Part of international effort to observe small changes in latitude. Credit: Coast & Geodetic Survey Historical Image Collection. |  | Observing longitude with Bamberg broken telescope instrument Astro party of George D. Cowie. Credit: Coast & Geodetic Survey Historical Image Collection. |
 | View from Buck Island Lagoon of east St. Croix. Telescope of National Radio Astronomy Observatory is visible. Credit: America's Coastlines. |  | Solar telescope tower at South Pole Station. Credit: Paths Less Taken - NOAA at the Ends of the Earth. |
Source: pictures compiled by the editor from various references; see picture credits. | |||
 |  |
| "Close up seaside telescope" by Simon Cataudo Commentary: "Close up of the beach telescope. Taken 13 September 2003." | "Focus" by Erik Dungan Commentary: "This is part of a coin-operated telescope on the pier. I like the textures and think the word-image might be useful." |
Source: photographs selected by the editor, with permission from the photographers. | |
| Author | Quotation |
H. W. Beecher | Tears are often the telescope by which men see far into heaven. |
Henry Ward Beecher | The soul without imagination is what an observatory would be without a telescope. |
Josh Rillings | Love looks through a telescope; envy, through a microscope. |
Victor Hugo | Where the telescope ends, the microscope begins. Which of the two has the grander view? |
Source: compiled by the editor from various references. | |
| Title | Author | Quote |
Les Miserables | Hugo, Victor | Where the telescope ends, the microscope begins |
Source: compiled by the editor from various references. | ||
| Subject | Topic | Quote |
Health | The urethra is the tube that carries urine from the bladder to the outside of the body. The cystoscope has lenses like a telescope or microscope. (references) | |
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
| Speaker | Term | Phrase(s) |
Ronald Reagan | 1981-1989 | Astronomers build a space telescope that can see to the edge of the universe and possibly back to the moment of creation. |
Source: compiled by the editor from various references. | ||
| "Telescope" is generally used as a noun (singular) -- approximately 98.92% of the time. "Telescope" is used about 464 times out of a sample of 100 million words spoken or written in English. Its rank is based on over 700,000 words used in the English language. Some parts-of-speech are not covered due to the samples used by the British National Corpus. (note: percents less than one-hundredth of one percent have been omitted) |
| Parts of Speech | Percent | Usage per 100 Million Words | Rank in English |
| Noun (singular) | 98.92% | 459 | 12,771 |
| Lexical Verb (infinitive) | 0.86% | 4 | 175,879 |
| Lexical Verb (base form) | 0.22% | 1 | 339,140 |
| Total | 100.00% | 464 | N/A |
Source: compiled by the editor from several corpora; see credits.
Expressions using "telescope": Achromatic telescope ♦ Aplanatic telescope ♦ astronomical telescope ♦ Axis of a telescope ♦ Cassegrainian telescope ♦ coude telescope ♦ Dialytic telescope ♦ dioptric telescope ♦ Equatorial telescope ♦ finder telescope ♦ Focal distance of a telescope ♦ Galactic Exoplanet Survey Telescope ♦ galilean telescope ♦ gregorian telescope ♦ Herschelian telescope ♦ Hubble Space Telescope ♦ Hubble Telescope ♦ Maksutov telescope ♦ newtonian telescope ♦ optical telescope ♦ photographic telescope ♦ prism telescope ♦ pyrometric telescope based on rotatory polarisation ♦ radio telescope ♦ reflecting telescope ♦ refracting telescope ♦ Schmidt reflecting telescope ♦ Schmidt telescope ♦ Sciotheric telescope ♦ sighting telescope ♦ solar telescope ♦ star telescope ♦ Telescope bag ♦ telescope box ♦ Telescope carp ♦ Telescope fish ♦ Telescope fly ♦ telescope or microscope ♦ Telescope shell ♦ telescope sight ♦ Terrestrial telescope ♦ Very Energetic Radiation Imaging Telescope Array System ♦ Visible and Infrared Survey Telescope for Astronomy ♦ water telescope ♦ zenith telescope. Additional references. | |
| Hypenated Usage | |
Ending with "telescope": radio-telescope. | |
| Source: compiled by the editor from various references; see credits. | |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Expression | Frequency per Day | Expression | Frequency per Day |
telescope | 3,670 | telescope for sale | 50 |
hubble space telescope | 1,149 | telescope mirror | 49 |
hubble telescope | 966 | reflector telescope | 47 |
meade telescope | 724 | hubble space telescope picture | 46 |
bushnell telescope | 643 | brass telescope | 45 |
hubble telescope image | 629 | dobsonian telescope | 45 |
orion telescope | 494 | telescope making | 41 |
space telescope | 240 | telescope picture | 38 |
sky and telescope | 236 | telescope history | 38 |
hubble space telescope image | 212 | mead telescope | 37 |
galileo telescope | 151 | telescope patio furniture | 36 |
telescope review | 145 | build telescope | 33 |
hubble telescope picture | 120 | discovery telescope | 33 |
celestron telescope | 114 | hubbell telescope | 33 |
radio telescope | 60 | hale site telescope | 33 |
telescope furniture | 59 | sky and telescope magazine | 33 |
hale telescope | 55 | telescope eyepiece | 32 |
tasco telescope | 52 | hubble telescope photo | 31 |
telescope part | 50 | reflecting telescope | 30 |
used telescope | 50 | obsession telescope | 30 |
| Source: compiled by the editor from various references; see credits. | |||
| Language | Translations for "telescope"; alternative meanings/domain in parentheses. | |
Albanian | teleskop, zgjat (delay, elongate, extend, hold out, last, lengthen, let down, linger, postpone, prolong, protract, reach, reach out, spread, stretch), futen brenda njëri-tjetrit. (various references) | |
Arabic | منظار (field glasses, glass, viewer), مقراب, تلسكوب, تداخل بعضه ببعض, ضغط (bear in mind, compress, compressing, compression, crowd, depress, duress, force, hustle, jam, lay stress on smth., lean, lobby, lobbying, pinch, press, pressure, push, screw, smash, squeeze, strain, stress, tension). (various references) | |
Bulgarian | сплесквам (flatten, jump). (various references) | |
Chinese | 望远镜 (telescopic), 望遠鏡 . (various references) | |
Czech | teleskop (night-glass), zasunout (slip, slip in, stick in), vklínit do sebe, komprimotovat, dalekohled (binoculars, field glasses). (various references) | |
Danish | teleskoproer for kulisaetning (coal drop sleeve, drop sleeve, feed sleeve, telescopic section), teleskoproer for kulindfyldning (coal drop sleeve, drop sleeve, feed sleeve, telescopic section), teleskop, sigtekikkert (sighting telescope). (various references) | |
Dutch | telescoop (reflecting telescope). (various references) | |
Esperanto | teleskopo. (various references) | |
Farsi | تلکسوپ , تلسکوپ بکاربردن , دوربین نجومی . (various references) | |
Finnish | teleskooppi, kaukoputki. (various references) | |
French | télescope (reflecting telescope, telescopic section). (various references) | |
German | Teleskop (glass), Fernrohr (binocular, binoculars, glass). (various references) | |
Greek | τηλεσκόπιο (field glass). (various references) | |
Hebrew | משקפת (binocular, binoculars, fieldglasses, spyglass), מקרבת. (various references) | |
Hungarian | távcső (bearing support, glass), messzelátó (field glasses, glass, longsighted, spy glass). (various references) | |
Indonesian | teropong (binoculars), keker (binoculars, spyglass). (various references) | |
Italian | telescopio (reflecting telescope), cannocchiale (binoculars, spyglass). (various references) | |
Japanese Kanji | 遠眼鏡 , テルミット反応 (combination television and video-recorder, facsimile through television, home shopping network, tape recorder, telecast, telecine, telecommunication, teleconference, telecontrol system, teleconverter, telegenic, telegraph, telekinesis, telepathy, telephone club, telescan, teletex, teletext, Teletopia, teletype, teletypewriter, teletypewriter exchange, television, television camera, television continuity, television game, television network, television rating system, television set, television shopping, television talent, telex, tellurium, terebinthina, thermit reaction, trekking, TV, video game), 望遠鏡 , 望遠鏡 . (various references) | |
Japanese Katakana | テレスコープ , ぼうえんきょう, とおめがね. (various references) | |
Korean | 망원경 (telescopic). (various references) | |
Manx | fodreayrtan, cur stiagh er y cheilley. (various references) | |
Papiamen | teleskop. (various references) | |
Pig Latin | elescopetay.(various references) | |
Portuguese | telescópio (coal drop sleeve, drop sleeve, feed sleeve, reflecting telescope, telescopic section). (various references) | |
Romanian | telescopa, telescop, se ciocni (bump, collide, conflict, dash against, encounter, fall foul of, foul, go foul of, hit, impinge, jar, knock, meet, run foul of, strike), lunetã (glass, lunette, steady). (various references) | |
Russian | телескоп. (various references) | |
Serbo-Croatian | teleskop, uvući jedno u drugo, skratiti (abbreviate, abridge, curtail, cut short, detruncate, foreshorten, reduce, shorten, syncopate, truncate), skraćivati (make shorter, shorten), sklopiti guranjem jedno u drugo. (various references) | |
Spanish | telescopio (prospect glass). (various references) | |
Swedish | teleskop, kikare (binoculars, fieldglass, field-glass). (various references) | |
Thai | กล้องโทรทรรศน์. (various references) | |
Turkish | teleskop, iç içe geçmek, dürbün (binoculars, field glass, field glasses). (various references) | |
Ukrainian | стикатися (clash, collide, contact, encounter, foul, impinge, impinge on, jostle, meet, osculate, touch), телескопічний (telescopic), телескоп, висуватися (poke), висувати (advance, bring forward, offer, promote, pull out, push, put forward, recommend, shoot out), оптична труба. (various references) | |
Vietnamese | kính thiên văn. (various references) | |
| Source: compiled by the editor from various translation references. | ||
| Language | Period | Translations |
| Greek | 700 BCE-300 CE | teleskopos. (various references) |
| Source: compiled by the editor from various references. | ||
Derivations | |
Words beginning with "telescope": telescoped, telescopes. (additional references) | |
| |
"Telescope" is suggested in spellcheckers for the following: telascope, teleoscope, telescoope, telescop, teliscope, telscope. (additional references) | |
| Source: compiled by the editor, based on several corpora (additional references). | |
| # of Phoneme Matches | Pronunciation | Word(s) rhyming with "telescope" (pronounced te"luskō'p) |
| 6 | -l u s k ō' p | oscilloscope. |
| 5 | -u s k ō' p | gastroscope, gyroscope, horoscope, kaleidoscope, microscope, ophthalmoscope, periscope, polariscope, stethoscope. |
Source: compiled by the editor (additional references); see credits. | ||
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "c-e-e-e-l-o-p-s-t" | |
-2 letters: celeste, steeple. | |
-3 letters: clepes, closet, elects, elopes, pestle, select, tepees, topees. | |
-4 letters: celts, cepes, cetes, clepe, clept, clops, close, clots, coles, colts, copes, copse, coset, cotes, elect, elope, epees, escot, estop, leets, lopes, peels, peles, pelts, pesto, plots, poets, poles, scope, sleep, sleet, slept, slope, socle, speel, spelt, steel, steep, stele, stole, stope. | |
| Words containing the letters "c-e-e-e-l-o-p-s-t" | |
+1 letter: telescoped, telescopes. | |
+3 letters: completeness, electroscope, electrotypes, preelections, preselection. | |
+4 letters: electrophiles, electroplates, electroscopes, electrotypers, overspeculate, preadolescent, preselections, splenectomies, splenectomize. | |
+5 letters: cephalometries, clothespresses, completenesses, electrodeposit, electrophorese, incompleteness, metencephalons, overspeculated, overspeculates, pinealectomies, poeticalnesses, preadolescents, splenectomized, splenectomizes, telencephalons, teleprocessing. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
