“protoplanet”的概念、定义、翻译、参考文献-科学参考

protoplanet

Physics

A large body of matter that is postulated to play a role in the formation of a planet. Protoplanets are formed from planetisimals and are held together by gravity; they are between about 100 and 1000 km in size. The interior of a protoplanet will have undergone melting due to impacts, gravitation, and the presence of radioactive elements, resulting in an internal structure in which heavier elements sink to the centre. The first direct observation of a protoplanet was in 2013.

Astronomy

A body presumed to have formed in the early history of the Solar System, from which the major planets grew. Protoplanets are believed to have formed from the aggregation of planetesimals. They eventually became the major planets by sweeping up other bodies that crossed their orbits, in a process of accretion.

Geology and Earth Sciences

An individual condensation, representing a very small proportion of the total cloud mass but of similar composition, that occurs during the condensation of an interstellar cloud, from which stars and planets are assumed to have originated. See protostar.

单词	protoplanet
释义	protoplanet Physics A large body of matter that is postulated to play a role in the formation of a planet. Protoplanets are formed from planetisimals and are held together by gravity; they are between about 100 and 1000 km in size. The interior of a protoplanet will have undergone melting due to impacts, gravitation, and the presence of radioactive elements, resulting in an internal structure in which heavier elements sink to the centre. The first direct observation of a protoplanet was in 2013. Astronomy A body presumed to have formed in the early history of the Solar System, from which the major planets grew. Protoplanets are believed to have formed from the aggregation of planetesimals. They eventually became the major planets by sweeping up other bodies that crossed their orbits, in a process of accretion. Geology and Earth Sciences An individual condensation, representing a very small proportion of the total cloud mass but of similar composition, that occurs during the condensation of an interstellar cloud, from which stars and planets are assumed to have originated. See protostar.
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