Nebula

A nebula^[1] is an interstellar cloud of dust, hydrogen, helium and other ionized gases in a galaxy.

The Persian astronomer, Abd al-Rahman al-Sufi, mentioned a true nebula for the first time in his book, Book of Fixed Stars (964).^[2] He said that there was a "little cloud" near the Andromeda galaxy.^[3]

↑ Latin for "cloud"; pl. nebulae, nebulæ, or nebulas. Nebula, Online Etymology Dictionary
↑ Kenneth Glyn Jones 1991. Messier's nebulae and star clusters. Cambridge University Press. p1 ISBN 0521370795
↑ Harrison, T.G. (March 1984). "The Orion Nebula — where in history is it". Royal Astronomical Society Quarterly Journal. 25 (1): 70–73. Bibcode:1984QJRAS..25...65H.

[1] Latin for "cloud"; pl. nebulae, nebulæ, or nebulas. Nebula, Online Etymology Dictionary

[2] Kenneth Glyn Jones 1991. Messier's nebulae and star clusters. Cambridge University Press. p1 ISBN 0521370795

[rasqj25-3] Harrison, T.G. (March 1984). "The Orion Nebula — where in history is it". Royal Astronomical Society Quarterly Journal. 25 (1): 70–73. Bibcode:1984QJRAS..25...65H.

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