Lectures on Astronomy: Delivered at King's College LondonJ. W. Parker, 1839 - 216 pages |
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Common terms and phrases
ABERRATION OF LIGHT actual altitude angle angular aphelion apparent diameter apparent motion appear ascertained astronomy bodies called celestial meridian celestial sphere circle clock comet cone of sunlight continually daily motion declination-circle described direction disc distance earth's axis earth's centre earth's orbit earth's surface eastward ecliptic enlightened hemisphere equal equator equinoctial fixed stars greater greatest heavens horizon hypothesis inclined infinitely intersect Jupiter latitude laws of attraction length let us suppose light and heat lines drawn longitude mass mean solar meridian of Greenwich miles moon moon's move night nodes number of degrees obliquely observer opposite orbit parallax parallel path perihelion period perpendicular planets pole portion precisely radius real motion reason relative positions revolve round right ascension round the earth round the sun Saturn seen shadow shown sidereal day solar day solar eclipse space sphere sun's synodic tion Uranus velocity Venus visible whilst whole zenith
Popular passages
Page 166 - Graeco-Egyptian mathematician and geographer who believed that the earth was the centre of the universe and that the sun and planets revolved around it.
Page 205 - ... to be some cause in operation by which the brilliancy of comets is continually diminishing. That of Halley, in one of its preceding revolutions, is described as giving a degree of light certainly superior to that which it gave in 1682 and 1759. Sir John Herschel could only see Biela's comet through a reflecting telescope of twenty feet in length, an instrument of enormous power in the collection of light...