Americanastronomer. He discovered 16 comets, including in 1892 the first comet to be discovered photographically. Also in 1892 he found Amalthea, the fifth satellite of Jupiter. He pioneered the photography of Milky Way starfields, publishing a catalogue of star-poor regions now known to be dark nebulae. His catalogue numbers (prefixed by B) are still in use. In 1916 he discovered Barnard's Star.
Subjects: Astronomy and Astrophysics.