Protoplanetary nebula

Forty years ago it was still a protoplanetary nebula in which the gas had not yet become hot and ionized.

Such features are also seen in Galactic carbon-rich protoplanetary nebulae.

'Rock' is used to describe compounds with high melting points that remained solid under almost all conditions in the protoplanetary nebula.

In the plural ansae, in astronomy, compact nebulosities such as can be found in protoplanetary nebulae.

Westbrook Nebula (CRL 618) is an aspherical protoplanetary nebula.

The Boomerang Nebula is a protoplanetary nebula located 5,000 light-years away from Earth in the constellation Centaurus.

Diacetylene has been identified in the atmosphere of Titan and in the protoplanetary nebula CRL 618 by its characteristic vibrational modes.

The Red Rectangle Nebula, so called because of its red color and unique rectangular shape, is a protoplanetary nebula in the Monoceros constellation.

The Cotton Candy Nebula is a protoplanetary nebula that was originally discovered by the IRAS satellite.

The name protoplanetary nebula is an unfortunate choice due to the possibility of confusion with the same term being sometimes employed when discussing the unrelated concept of protoplanetary disks.

While most Be stars are on the main sequence, the identifier actually refers to a heterogeneous group of objects including pre main sequence stars, supergiant stars, protoplanetary nebulae, and others.

Indeed, the cosmic synthesis of nanocrystalline diamond may be occurring today in so-called protoplanetary nebulae, a relatively brief stage in the evolution of red-giant stars, which our own sun will enter in the far distant future.

The objects of the inner Solar System are composed mostly of rock, the collective name for compounds with high melting points, such as silicates, iron or nickel, that remained solid under almost all conditions in the protoplanetary nebula.

Iro et al., trying to interpret the nitrogen deficiency in comets, stated most of the conditions for hydrate formation in the protoplanetary nebulae, surrounding the pre-main and main sequence stars were fulfilled, despite the rapid grain growth to meter scale.

Circumstellar envelopes of the old stars (Mira variables and OH/IR stars) are eventually evolving into Protoplanetary nebulae, and circumstellar envelopes of the young stellar objects are evolving into Circumstellar discs.

The name protoplanetary nebula is a consequence of the older term planetary nebula, which was chosen due to early astronomers looking through telescopes and finding a similarity in appearance of planetary nebula to the gas giants such as Neptune and Uranus.

Systems that can be strongly influenced by the dynamics of preferential concentration are aerosol production of fine powders, spray, emulsifier, and crystallization reactors, pneumatic devices, cloud droplet formation, aerosol transport in the upper atmosphere, and even planet formation from protoplanetary nebula.