UNIVERSE
COMETS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A collection of stars, dust, and gas bound together by gravity .
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have a huge bulge at the center and spiral arms made up of gas, dust, and new stars.
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Either A or B
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None of the above
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Detailed explanation-1: -A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems. A galaxy is held together by gravity. Our galaxy, the Milky Way, also has a supermassive black hole in the middle. When you look up at stars in the night sky, you’re seeing other stars in the Milky Way.
Detailed explanation-2: -A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction. A large group of stars bound by gravitation is generally called a star cluster or galaxy, although, broadly speaking, they are also star systems.
Detailed explanation-3: -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-4: -Stars form in the densest regions of the interstellar medium, or ISM, called molecular clouds. The ISM is the name given to the gas and dust that exists between the stars within a galaxy. It is 99% gas and 1% dust, by mass. Properties of ISM gas in our region of the Milky Way Galaxy: 70% hydrogen.