Astronomical Observatory of Harvard College: Miscellaneous PapersHarvard College, 1888 |
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Halaman 230
... diameters in front of the object - glass of the telescope . By alternating between bright and faint images of the same star , on different groups of the transit threads , the personal equation between bright and faint stars can be found ...
... diameters in front of the object - glass of the telescope . By alternating between bright and faint images of the same star , on different groups of the transit threads , the personal equation between bright and faint stars can be found ...
Halaman 241
... diameter of 30 inches , one second of arc is equal to .0000727 of an inch . It appears , therefore , from this ... diameters , while the magnifying powers used in this series of measures were 194 , 290 , 560 , and 870. Moreover , this ...
... diameter of 30 inches , one second of arc is equal to .0000727 of an inch . It appears , therefore , from this ... diameters , while the magnifying powers used in this series of measures were 194 , 290 , 560 , and 870. Moreover , this ...
Halaman 252
... diameter of that planet , as well as of its ingress and egress . The weather , unfortunately , seriously interfered with these observations . Photographs of the transit were also taken in co - operation with the U. S. Naval Observatory ...
... diameter of that planet , as well as of its ingress and egress . The weather , unfortunately , seriously interfered with these observations . Photographs of the transit were also taken in co - operation with the U. S. Naval Observatory ...
Halaman 254
... diameter , and weighs about two hundred and fifty pounds . It has a fall of about fifteen feet , and is held in place , when raised to the top of its mast , by a powerful electro - magnet . It is released at noon by the clock at ...
... diameter , and weighs about two hundred and fifty pounds . It has a fall of about fifteen feet , and is held in place , when raised to the top of its mast , by a powerful electro - magnet . It is released at noon by the clock at ...
Halaman 269
... diameter . In my own case the sense of touch has been so far cultivated that I am able to make 100 successive contacts without a single deviation exceeding .000035 inch , and very few deviations reach .000010 inch . A comparator of this ...
... diameter . In my own case the sense of touch has been so far cultivated that I am able to make 100 successive contacts without a single deviation exceeding .000035 inch , and very few deviations reach .000010 inch . A comparator of this ...
Istilah dan frasa umum
accuracy Algol angle Argelander assumed Astron Astronomical Astronomische azimuths bands binary brighter brightness catalogue Cephei Coast Survey column gives Comet compared comparison stars computed correction corresponding determined diameter difference distance double stars Durchmusterung eclipse ephemeris equal equation equatorial estimate faint fainter formula fundamental stars Geminorum given Harvard College Observatory inch increase instrument interval L-L₁ L₁ large telescope last column latitude length light curve lines logarithms longitude Lyræ M₁ magnitude mean Meridian Circle meridian photometer meter method Mètre micrometer microscope minima minimum minutes motion nearly nebula objects obtained orbit period photometric photometric measures PICKERING plane planetary nebula plate position precision present probable error proper motion reduced Report residuals right ascension satellite scale Schmidt Schönfeld screw spectra standard stellar magnitude systematic errors Table temperature tenths tion Uranometria variable stars variation in light yard zone
Bagian yang populer
Halaman 273 - ... the reader is referred to the references at the end of this chapter for further information.
Halaman 274 - Yard 1760" are engraved, shall be, and the same is hereby declared to be, the original and genuine standard of that measure of length or lineal extension called a yard ; and that the same straight line or distance between the centres of the said two points in the said gold studs in the said brass rod, the brass being at the temperature of 62 ° of Fahrenheit's thermometer, shall be and is hereby denominated the "Imperial Standard yard...
Halaman 310 - LENGTH-COMPARISONS of the STANDARDS of LENGTH of England, France, Belgium, Prussia, Russia, India, Australia, made at the Ordnance Survey Office, Southampton, by Captain AR CLARKE, RE, FRS, under the direction of Major-General Sir HENRY JAMES, RE, FRS, &c., Cor.
Halaman 311 - Sess. (1818-10), vol. vi., Doc. 109. Report on Weights and Measures, by JQ Adams, Sec. of State (Feb. 22, 1821). Executive Papers, 16th Cong., 2d Sess., Doc. 109. Report of Committee to whom was referred the Report of the Sec. of State. Reports of Committees, 17th Cong., 1st Sess. (1821-22), vol. ii., Doc. 65. Comparison of Weights and Measures of Length and Capacity, by FR Hassler.
Halaman 2 - Attach a microscope first to one end and then to the other end of the planer, and make the adjustment for level such that the surface of the mercury is sharply in focus under the microscope in the two positions. The bed-plate can then be blocked up at the intermediate points until every point is in focus. With regard to...
Halaman 24 - Lyree, ijAquilce, and 8 Cephei, have been observed with great care, so that their variations are known with much precision. Each will therefore be discussed in turn, according to the following method. As the variation is periodic, it will be convenient to denote the time by an angle, v, such that 360° shall correspond to one period or revolution of the star. We now wish the light * Poggendorff's Annalen, xxxiii.
Halaman 3 - Bache telescope has been employed. The third research relates to a more careful study of the spectra of the brightest stars. For this work Mrs. Draper has lent the 11-inch photographic lens employed by her husband. .She has also furnished an admirable mounting for the instrument, and a small observatory to contain it. Two prisms have been constructed to place in front of the object-glass, the large one having a clear aperture of eleven inches square, and an angle of nearly 15°.
Halaman 308 - Narrative of the Origin and Formation of the International Association for obtaining a Uniform Decimal System of Measures, Weights, and Coins.
Halaman 21 - Lyrce and 8 Cephei. V. Stars which every few days undergo for a few hours a remarkable diminution in light, this phenomenon recurring with great regularity. Examples, /3 Persei and S Cancri.
Halaman 312 - Commissioners appointed to consider the Steps to be taken for the Restoration of the Standards of Weight and Measure, by Airy, Baily, Bethune, Herschel, Lefevre, Lubbock, Peacock, and Sheepshanks.