planetesimal
2
9.9
- noun
- /ˌplænɪˈtɛsɪməl/
- Specialized
:
planetesimal
- Once rocky kilometer-sized objects, known as planetesimals, have formed, they can then coagulate to form either terrestrial-like planets or the cores of gas giant planets.
- planetesimal density
Examples
-
Reducing the planetesimal density by a factor of two increases the formation time for a planet but reduces the core mass.
Academic text (2004) -
According to the standard model of planet formation, planets build up from kilometer-sized planetesimals that can be made of ice, rock, or both.
Academic text (2003) -
Since the outer protoplanetary disk contains many more icy than rocky planetesimals, bigger planets can form there.
Academic text (2003) -
The answers are still being worked out on computers throughout the world, but one hypothesis is that enormous numbers of planetesimals form in the protoplanetary disk.
Academic text (2000) -
The accretion of additional planetesimals onto a newly forming core releases gravitational potential energy that can be used to support a gaseous envelope or atmosphere.
Academic text (2004) -
There is almost no question that the terrestrial planets formed from rocky planetesimals (the inner system was too hot to allow icy planetesimals).
Academic text (2003) -
During the formation of the solar system, many planetesimals collided and merged to form larger celestial bodies.
-
Scientists study planetesimals to understand how planets like Earth came to be in our early solar system.
-
The asteroid belt is made up of countless planetesimals that never formed into a full planet.
Compounds
- Specialized
A theory that says the solar system formed when small space rocks stuck together by gravity
How Developed
Surface Forms
Morphology
planetesimal = planet + infinitesimal (semi-transparent) = planet + esimal
The word is formed by blending 'planet' with the ending of 'infinitesimal', suggesting a very small planet-like body, though the exact scientific sense is specialized.
Etymology
Planetesimal comes from planet, from a Greek word meaning 'wanderer', plus the ending -esimal meaning 'small', so it literally means 'small planet'. That's why planetesimal is used for the tiny early bodies that joined to make the planets.