History of Astronomy |
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Page 129
... Sirius . In 1738 J. Cassini 3 showed that the former had moved five minutes of arc since Tycho Brahe fixed its position . In 1792 Piazzi noted the motion of 61 Cygni as given above . For a long time the greatest observed proper motion ...
... Sirius . In 1738 J. Cassini 3 showed that the former had moved five minutes of arc since Tycho Brahe fixed its position . In 1792 Piazzi noted the motion of 61 Cygni as given above . For a long time the greatest observed proper motion ...
Page 134
... Sirius being about half a century . Later he said : " I adhere to the conviction that Procyon and Sirius form real binary systems , consisting of a visible and an invisible star . There is no reason to suppose luminosity an essential ...
... Sirius being about half a century . Later he said : " I adhere to the conviction that Procyon and Sirius form real binary systems , consisting of a visible and an invisible star . There is no reason to suppose luminosity an essential ...
Page 135
... Sirius to be o " .38 . From this it has been calculated that the mass of Sirius equals two of our suns , and its intrinsic brightness equals twenty suns ; but the companion , having a mass equal to our sun , has only a five - hundredth ...
... Sirius to be o " .38 . From this it has been calculated that the mass of Sirius equals two of our suns , and its intrinsic brightness equals twenty suns ; but the companion , having a mass equal to our sun , has only a five - hundredth ...
Page 136
... Sirius and Procyon , leads to the inference that if ever the plane of such a binary orbit were edge - on to us there ought to be an eclipse of the luminous partner whenever the non - luminous one is interposed between us . This should ...
... Sirius and Procyon , leads to the inference that if ever the plane of such a binary orbit were edge - on to us there ought to be an eclipse of the luminous partner whenever the non - luminous one is interposed between us . This should ...
Page 144
... Sirius , Vega , Regulus , Altair . The characteristic feature of their spectra is the strength and breadth of the hydrogen lines and the extreme faintness of the metallic lines . This class of star is white to the eye , and rich in ...
... Sirius , Vega , Regulus , Altair . The characteristic feature of their spectra is the strength and breadth of the hydrogen lines and the extreme faintness of the metallic lines . This class of star is white to the eye , and rich in ...
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accepted accurate ancient appear astronomers attraction bodies bright calculations called catalogue cause centre century Chinese circle comet compared complete Copernicus determined diameter direction discovered discovery distance earth eclipse effect elements enabled epicycles equal error explain fact fixed follow force four Galileo gave give given gravitation heavens held Herschel increased interesting Jupiter Kepler knowledge known later LIBRARIES light lunar Mars mass mathematical mean measured method miles moon moon's motion move Newton noticed object observations Observatory opposition orbit original parallax pass period photographic physical planet planetary pole position predicted progress proper motion proved records researches revolve ring rotation round Royal satellites seems seen showed SIGILLUM solar system spectroscope spectrum stars studied sun's supposed surface tables telescope theory tion trace true Tycho Brahe UNIVERSITY VERITAS