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.
As described in Herndon's general article in Current Science, in the main planets formed directly by condensing and raining out from within giant gaseous protoplanets at high pressures and high temperatures.
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.
Scientists believe Ceres and Vesta are the right two bodies with which to address this question, as they are the most massive of the protoplanets, baby planets whose growth was interrupted by the formation of Jupiter.
Vesta is considered a protoplanet, or body that never quite became a full-fledged planet.
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.
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.
Rather, its geologically diversity and characteristics suggests it may be a remnant of a protoplanet, which scientists think are the embryonic building block of planets like earth.