Recent Examples of planetesimal from the Web
Dust grains grew into pebbles, and pebbles became world-building planetesimals.
These are thought to be fragments of the cores of planetesimals that formed early in the Solar System's history.
The planets formed in a disk of gas and dust surrounding the sun where dust collided together to make pebbles, and then pebbles came together to make planetesimals hundreds of kilometers wide.
The largest of these planetesimals grow faster than the ones around them and swallow their neighbors to grow into proto-planets.
Dwarf planets have been defined by the International Astronomical Union since 2006 as celestial bodies that are roundish like their larger cousins in the solar system, but which haven’t gobbled up all the other planetesimals near themselves.
In order for the theory to work, planetesimals had to be huge, and this family was one of the biggest.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'planetesimal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of planetesimal
First Known Use: 1903See Words from the same year
Seen and Heard
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