Cloud collapse

Giant molecular clouds collapse to form stars and solar systems, with planets and debris left over such as comets and meteorites. Are comets and meteorites the delivery vehicles that enable life to start on many planets and move between the planets as the solar system forms, providing water and molecules to seed life The planets have to be hospitable, however, and that seems to mean wet and... 

A sexy cloud collapses while smoking the moldy soul. 

Inheritance of 0-poor gas from the presolar molecular cloud is based on the well-known phenomenon of photochemical self-shielding, in which photolysis of CO in the cloud interior affects preferentially the less-abundant isotopic species C O and C O. Yurimoto and Kuramoto (2002) proposed that the and atoms thus formed can react with hydrogen to form water ice. When a portion of the cloud collapses to form the solar nebula, the ice evaporates to form a... 

Astronomical observations of molecular clouds and young stellar objects provide the basis for our understanding of the early solar system (Cameron, 1995 Alexander et al., 2001). The first stage in this process is when a fragment of an interstellar molecular cloud collapses to form a disk-like nebula, or proto-planetary disk. This process normally takes... 

Second, as the cloud begins to contract, it also begins to rotate. During rotation, some of the gas contained in the cloud is thrown outward, away from the center, where it forms a thin disk of material around the central core of the cloud. The more the cloud collapses, the faster it rotates and the more material it ejects into the surrounding disk. The disk that surrounds the cloud contains particles that may themselves coalesce to form small bodies (planets) that revolve around the young star. 

The overall picture is now clear. As a result of the variety of nuclear processes available to stars, the creation of nearly all of the known isotopes can he accounted for. Once these isotopes are formed in stars, they are released to the interstellar medium upon the star s demise. When they have become part of the ISM, these isotopes are available for capture by other young stars in the early stages of molecular cloud collapse and protostar formation. Surely stars are the ideal example of how recycling can benefit the environment ... 

The underlying premise of the cloud collapse theory is that the first bubbles to collapse are those at the periphery of a cavitation cloud, and they in turn transfer collapse energy to the core of the bubble cluster, thus intensifying water hammer pressures. 

Figure 1.26 The Vapor Cloud Collapses When Vapor is Condensed...

Consider the effect of inserting a colder (ambient or any sub-boiling temperature) basket of parts into that maelstrom of thermal effects. The hot vapor is condensed onto the colder surfaces, and the vapor cloud collapses. Figure 1.26 shows an idealized vision of that outcome. 

Cloud-collapse and stellar evolution depend on stellar mass. The higher the mass, the faster the collapse and the subsequent evolution. To descend the Hayashi track it takes... 

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