molecular cloud

[ muh-lek-yuh-ler kloud ]

noun

, Astronomy.

1. an interstellar cloud of gas and dust composed of hydrogen, helium, and other molecular remnants of a supernova. star formation ( def 1 ), stellar nursery ( def ).

molecular cloud

noun

1. a cool dense interstellar region composed of a wide variety of molecules, mainly hydrogen, plus some dust, in which stars are forming

Word History and Origins

Origin of molecular cloud¹

First recorded in 1970–75

Example Sentences

Image: Artist’s Impression of the “Tadpole” Molecular Cloud and the black hole at the gravitational center of its orbit.

From Space Scoop

The results help explain why stars born from the same molecular cloud can possess different chemical composition and host different planetary systems, as well as pose challenges to current stellar and planet formation models.

From Science Daily

These stellar pairs are born together out of the same molecular cloud from a shared abundance of chemical building blocks, so astronomers would expect to find that they have nearly identical compositions and planetary systems.

From Science Daily

The third possible explanation looks back at the beginning of the stars' formation, suggesting that the differences originate from primordial, or pre-existing, areas of nonuniformity within the molecular cloud.

From Science Daily

In simpler terms, if the molecular cloud has an uneven distribution of chemical elements, then stars born within that cloud will have different compositions depending on which elements were available at the location where each formed.

From Science Daily