protoplanet


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Related to protoplanet: protoplanetary, Protoplanet theory

protoplanet

(proh -toh-plan-it) An evolving planet in the process of accretion, together with any of its satellites forming by accretion at the same time in the vicinity of the planet. The dust cocoon around some T Tauri stars has the attributes of a protoplanetary system. In the one typical case, HL Tauri, it forms a flattened disk, radius 160 AU, containing about one Earth mass of dust; allowing for dust condensed into planetesimals and the system's gas content, it could condense into several planets. Infrared observations from the satellite IRAS show dust around over 40 slightly older stars, including Vega, indicating either a protoplanetary system or a swarm of comets. See also Beta Pictoris.

protoplanet

[′prōd·ō‚plan·ət]
(astronomy)
A precursor of one of the giant planets, which is believed to have formed, along with its satellites, from a minisolar nebula in a manner similar to that of the formation of the sun and planets.
References in periodicals archive ?
A team of scientists under Stephanie Sallum in Tucson, Arizona used adaptive optics observations to record these protons and thereby detect the formation of the protoplanet, which orbits a relatively young star just two million years old.
It involves devastating collisions with other small protoplanets, as well as with a multitude of showering, tumbling worldlets.
If we assume that a protoplanet took about a million years to lose most of its volatile elements, then c is found to be ~[10.
Furthermore, because of its mass, it would be concentrated at or near the surface of the forming protoplanets along with the other elements with similar masses in sufficient abundance for life molecules to form there with relative ease.
Dawn's exploration of protoplanet Vesta revealed to us that it was very similar to Earth than to typical asteroids.
These impish nicknames arise from the fundamental basis of the theory: a Mars-sized protoplanet, named Theia by astronomers, crashed into the primordial Earth billions of years ago.
It spent nearly 14 months orbiting and mapping Vesta, returning more than 30,000 images and other measurements of the protoplanet.
The observations were made using a special coronagraph in NACO, which operates at near-infrared wavelengths and suppresses the brilliant light coming from the star at the location of the protoplanet candidate.
The team found some of this gas drifting through the gap--probably leftover stuff that the protoplanet hadn't cleared away, Casassus says.
The team found some of this gas drifting through the gap - probably leftover stuff that the protoplanet hadn't cleared away, Casassus says.
Dawn set off to observe the protoplanet Vesta in 2007.
The Dawn mission, managed by JPL, surveyed the giant asteroid Vesta and the protoplanet, Ceres, between 2011 and 2015.