The Spectra of Comets 1950b (Minkowski) and 1951a (Pajdusakova).

The spectrum of Comet 1950b at heliocentric distance 2.65 A.U. shows a strong solar continuum concentrated in the nucleus and CN emission over a coma forty times larger. Comet 1951a at heliocentric distance 0.91 A.U. is very unusual in showing a strong nuclear continuum and extremely weak CN emission over a coma only eight times larger than the nucleus. The former seems normal for a comet distance from the sun; the latter is probably a "fresh" comet, newly arrived near the sun from the swarm of cometary material postulated by Oort at the outer confines of the solar system.