molecular cloud: meaning, definition, pronunciation and examples

Not exactly. A molecular cloud is a specific type of nebula—a dark, cold, and dense one where molecules can exist. Other nebulae, like emission or reflection nebulae, are often illuminated regions around molecular clouds.

Not directly, as they are often dark and opaque at visible wavelengths. They are best observed using telescopes that detect radio waves (like for carbon monoxide) or infrared light, which can penetrate the dust.

The collapse is typically triggered by an external disturbance, such as the shock wave from a nearby supernova explosion or the gravitational pull when clouds collide. This compression increases density until gravity takes over.

The initial collapse of a cloud core can take about 100,000 years, but the entire process from cloud fragment to a stable main-sequence star like our Sun can take tens of millions of years.

A dense region of gas and dust in interstellar space where molecules are abundant and stars can form.

Molecular cloud is usually technical/scientific in register.

Molecular cloud: in British English it is pronounced /məˌlek.jə.lə ˈklaʊd/, and in American English it is pronounced /məˌlek.jə.lɚ ˈklaʊd/. Tap the audio buttons above to hear it.