A contracting mass of gas which represents an early stage in the formation of a star, before nucleosynthesis has begun.
〔天文〕原恒星
Example sentencesExamples
Elongated chains of dust grains like these appear in the early stages of planet formation around a young protostar, according to a microgravity experiment inside a rocket.
In this, a passing protostar, loosely held together, passes close to our Sun whose gravity pulls off a filament of the star's material, which breaks up into segments that become six planets (not the current nine).
By peering in wavelengths not visible to the naked eye, through the nebula's gas and dust, astronomers can identify very young stars and even protostars - those that are about to light up, once the gases reach a critical density.
We already knew that planets form in the disks of gas and dust that surround young protostars.
Rotation forces some of the matter to accumulate in a disk rotating around the protostar (s).
Definition of protostar in US English:
protostar
nounˈproʊdəˌstɑrˈprōdəˌstär
Astronomy
A contracting mass of gas which represents an early stage in the formation of a star, before nucleosynthesis has begun.
〔天文〕原恒星
Example sentencesExamples
Elongated chains of dust grains like these appear in the early stages of planet formation around a young protostar, according to a microgravity experiment inside a rocket.
By peering in wavelengths not visible to the naked eye, through the nebula's gas and dust, astronomers can identify very young stars and even protostars - those that are about to light up, once the gases reach a critical density.
In this, a passing protostar, loosely held together, passes close to our Sun whose gravity pulls off a filament of the star's material, which breaks up into segments that become six planets (not the current nine).
Rotation forces some of the matter to accumulate in a disk rotating around the protostar (s).
We already knew that planets form in the disks of gas and dust that surround young protostars.