author catalogue of nebulae and clusters of stars
Caroline Lucretia Herschel ( 16 March 1750  9 January 1848 ) was a German astronomer , whose most significant contributions to astronomy were the discoveries of several comets , including the periodic comet 35P / Herschel - Rigollet , which bears her name . She was the sister of astronomer William Herschel , with whom she worked throughout her career . A composer ( Latin " compn "; literally " ___MASK94___ who puts together ") is a person who creates or writes music , which can be vocal music ( for a singer or choir ), instrumental music ( e . g ., for solo piano , string quartet , wind quintet or orchestra ) or music which combines both instruments and voices ( e . g ., opera or art song , which is a singer accompanied by a pianist ). The core meaning of the term refers to individuals who have contributed to the tradition of Western classical music through creation of works expressed in written musical notation ( e . g ., sheet music scores ). A comet is an icy small Solar System body that , when passing close to the Sun , warms and begins to evolve gasses , a process called outgassing . This produces a visible atmosphere or coma , and sometimes also a tail . These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet . Comet nuclei range from a few hundred metres to tens of kilometres across and are composed of loose collections of ice , dust , and small rocky particles . The coma may be up to 15 times the Earth ' s diameter , while the tail may stretch ___MASK94___ astronomical unit . If sufficiently bright , a comet may be seen from the Earth without the aid of a telescope and may subtend an arc of 30 ° ( 60 Moons ) across the sky . Comets have been observed and recorded since ancient times by many cultures . Sir ___MASK40___ , 1st Baronet ( 7 March 1792  11 May 1871 ) was an English polymath , mathematician , astronomer , chemist , inventor , and experimental photographer , who also did valuable botanical work . He was the son of Mary Baldwin and astronomer William Herschel , nephew of astronomer Caroline Herschel and the father of twelve children . The New General Catalogue of Nebulae and Clusters of Stars ( abbreviated as NGC ) is a catalogue of deep - sky objects compiled by John Louis Emil Dreyer in 1888 as a new version of John Herschel ' s " General Catalogue of Nebulae and Clusters of Stars ". The NGC contains 7 , 840 objects , known as the NGC objects . It is ___MASK94___ of the largest comprehensive catalogues , as it includes all types of deep space objects and is not confined to , for example , galaxies . Dreyer also published two supplements to the NGC in 1895 and 1908 , known as the Index Catalogues , describing a further 5 , 386 astronomical objects . Frederick William Herschel , (" Friedrich Wilhelm Herschel "; 15 November 1738  25 August 1822 ) was a British astronomer and composer of German origin , and brother of fellow astronomer Caroline Herschel , with whom he worked . Born in the Electorate of Hanover , Herschel followed his father into the Military Band of Hanover , before migrating to Great Britain in 1757 at the age of nineteen . The Catalogue of Nebulae and Clusters of Stars ( CN ) is an astronomical catalogue of nebulae first published in 1786 by William Herschel , with the assistance of his sister Caroline Herschel . It was later expanded into the General Catalogue of Nebulae and Clusters of Stars ( GC ) by his son , John Herschel . The CN and GC are the precursors to John Louis Emil Dreyer ' s New General Catalogue used by current astronomers .