which matter is found in this medium?
This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays.
Interstellar medium
This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays.
difference between solar nebula theory and nebular hypothesis The widely accepted modern variant of the nebular theory is the solar nebular disk model (SNDM) or solar nebular model. It offered explanations for a variety of properties of the Solar System what is this hypothesis? The Nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System. what does it say about rocky planets? According to the solar nebular disk model, rocky planets form in the inner part of the protoplanetary disk, within the frost line, where the temperature is high enough to prevent condensation of water ice and other substances into grains. does it say anything about protostars? Yes, Gas in the central part of the nebula, with relatively low angular momentum, undergoes fast compression and forms a hot hydrostatic core.  The core gradually grows in mass until it becomes a young hot protostar. when was this type of star discovered? The modern picture of protostars, summarized above, was first suggested by Chushiro Hayashi in 1966 is there anything particular about their evolution? Star formation begins in relatively small molecular clouds called dense cores.  As the dense core accrues mass from its larger, surrounding cloud, self-gravity begins to overwhelm pressure, and collapse begins. what are these clouds? A molecular cloud, sometimes called a stellar nursery (if star formation is occurring within), is a type of interstellar cloud, the density and size of which permit the formation of molecules, most commonly molecular hydrogen (H). where do they occur? Within the Milky Way, molecular gas clouds account for less than one percent of the volume of the interstellar medium (ISM), yet it is also the densest part of the medium.
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Interstellar medium [SEP] Introduction
In astronomy, the interstellar medium (ISM) is the matter and radiation that exists in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic space. The energy that occupies the same volume, in the form of electromagnetic radiation, is the interstellar radiation field. The interstellar medium is composed of multiple phases distinguished by whether matter is ionic, atomic, or molecular, and the temperature and density of the matter. The interstellar medium is composed, primarily, of hydrogen, followed by helium with trace amounts of carbon, oxygen, and nitrogen comparatively to hydrogen.