GK
THE UNIVERSE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Galaxies
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Star
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Nebulae
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Black holes
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Detailed explanation-1: -Hot clouds of gaseous elements and compounds called nebulae serve as nurseries for stars. As these nebulae spin, they slowly condense, raising their temperature and forming stars. Galaxies are made of millions of stars, interstellar gas, and dust that stay relatively close together due to gravity.
Detailed explanation-2: -The Short Answer: A nebula is a giant cloud of dust and gas in space. Some nebulae (more than one nebula) come from the gas and dust thrown out by the explosion of a dying star, such as a supernova. Other nebulae are regions where new stars are beginning to form.
Detailed explanation-3: -What elements are stars mostly made of? How do we know this? Stars are mostly made of hydrogen and helium. We know this by analyzing the relative strengths of absorption lines in their spectra.
Detailed explanation-4: -Centrifugal force causes the outer part of a collapsing interstellar cloud to flatten into a disk, where planets are formed. Source: The Birth of Stars, by NASA.