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  2. Molecular cloud - Wikipedia

    en.wikipedia.org/wiki/Molecular_cloud

    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 absorption nebulae, the formation of molecules (most commonly molecular hydrogen, H 2), and the formation of H II regions.

  3. Stellar evolution - Wikipedia

    en.wikipedia.org/wiki/Stellar_evolution

    A star of less than about half the mass of the Sun will be unable to ignite helium fusion (as noted earlier), and will produce a white dwarf composed chiefly of helium. In the end, all that remains is a cold dark mass sometimes called a black dwarf. However, the universe is not old enough for any black dwarfs to exist yet.

  4. Compact object - Wikipedia

    en.wikipedia.org/wiki/Compact_object

    A star in this hypothetical state is called a "quark star" or more specifically a "strange star". The pulsar 3C58 has been suggested as a possible quark star. Most neutron stars are thought to hold a core of quark matter but this has proven difficult to determine observationally. [citation needed]

  5. Star formation - Wikipedia

    en.wikipedia.org/wiki/Star_formation

    The W51 nebula in Aquila - one of the largest star factories in the Milky Way (August 25, 2020). Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as "stellar nurseries" or "star-forming regions", collapse and form stars. [1]

  6. Interstellar medium - Wikipedia

    en.wikipedia.org/wiki/Interstellar_medium

    The densest molecular clouds have significantly higher pressure than the interstellar average, since they are bound together by their own gravity. When stars form in such clouds, especially OB stars, they convert the surrounding gas into the warm ionized phase, a temperature increase of several hundred.

  7. Nasa finds key life building block carbon molecule in cosmic ...

    www.aol.com/nasa-finds-key-life-building...

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  8. Gravitational collapse - Wikipedia

    en.wikipedia.org/wiki/Gravitational_collapse

    Star formation involves a gradual gravitational collapse of interstellar medium into clumps of molecular clouds and potential protostars. The compression caused by the collapse raises the temperature until thermonuclear fusion occurs at the center of the star, at which point the collapse gradually comes to a halt as the outward thermal pressure ...

  9. Star - Wikipedia

    en.wikipedia.org/wiki/Star

    The formation of a star begins with gravitational instability within a molecular cloud, caused by regions of higher density—often triggered by compression of clouds by radiation from massive stars, expanding bubbles in the interstellar medium, the collision of different molecular clouds, or the collision of galaxies (as in a starburst galaxy).