The Sun: Ruler, Fire, Light, and Life of the Planetary System

angle aperture aphelion appear astronomers atmosphere battery of prisms body bright lines cause centre chromosphere clouds coloured consider corresponding dark lines deduced diameter direction dispersion Earth eclipse effect equal error estimate exact fact faculæ Fraunhofer greater Halley's method heat Herschel Hipparchus Kirchhoff length less light-waves limb limits luminous Mars mass matter mean distance measure miles per second Moon Moon's motion noticed observations orbit pass path peculiarity penumbra perihelion phenomena photosphere planets portion present problem prominences proportion rays recognised red end refrangibility regarded researches respecting rotation Secchi seen Sir William Herschel slit sodium solar light solar parallax solar physics solar prominences solar spectrum solar spots source of light space spec spectra spectroscopic analysis star stations Sun can control Sun-spots Sun's disc Sun's distance Sun's surface supposed telescope terrestrial tion transit transits of Venus trum Uranus vapours velocity Venus violet end visible