Assertion: nebula's star | /r/CapableOf | form in the center
Facets:
value: under the section formation
type: LOCATION
value: as the material contracts
type: TEMPORAL
Source sentences:
text: As the material contracts, massive stars may form in the center, and their ultraviolet radiation ionises the surrounding gas, making it visible at optical wavelengths.
text: Massive stars may form in the center, and their ultraviolet radiation ionizes the surrounding gas, making it visible at optical wavelengths.
text: As the material collapses contracts, massive stars may form in the center, and their ultraviolet radiation ionises the surrounding gas, making it visible at optical wavelengths.
text: As the material collapses under its own weight, massive stars may form in the center, and their ultraviolet radiation ionizes the surrounding gas, making it visible at optical wavelengths.
text: According to the English wikipedia article on nebulae, under the section Formation, «as the material collapses under its own weight, massive stars may form in the center, and their ultraviolet radiation ionizes the surrounding gas, making it visible at optical wavelengths.