The of the stars depend upon the gravitational

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The _______________ of the stars depend upon the gravitational attraction for them within their galaxy and upon the mass of the star. : Velocity. The velocity of a star consists of both the magnitude and direction of a star's movement and denotes both the speed and direction a body is moving. According to Newton's law of gravity, given a certain amount of gravitational attraction, a massive star will move more slowly than a star with less mass (obviously, a star with less mass will take less force to move).
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Galaxy Types, the Big Bang, the Sun and Moon's effects on the Earth The vast majority of observed ____________ fall into two general classes: spirals and elliptical. Explanation: Galaxies. In addition, a small minority of galaxies are classed as irregular. Our own galaxy (the Milky Way) and M31 (the Andromeda Galaxy) are both typical ______________ galaxies. Explanation: Spiral. A spiral consists of a nucleus, a disk, a corona, and spiral arms. Interstellar material is usually observed in the arms of spiral galaxies and bright emission nebulae are present. Other famous spiral galaxies include M81 - Bodes Galaxy (left image below) and M33 - Traingulum Galaxy (right image): While more than two-thirds of the most conspicuous galaxies in the sky are spirals, there are many dwarf galaxies which fall into the class of ______________ galaxies. Explanation: Elliptical. Elliptical galaxies are spherical or ellipsoidal systems which consist entirely of stars with no trace of spiral arms. The distribution of ________________ in a typical elliptical galaxy shows that while it has many stars concentrated toward its center, a sparse scattering of stars extends for very great distances and merges imperceptibly into the void of intergalactic space. : Light. This scattering of outlying stars makes determining the total size of an elliptical galaxy difficult. The fact that elliptical galaxies are not disk-shaped shows that they are not rotating as rapidly as the spirals. Elliptical galaxies have a much greater range in size, mass, and _______________ than do the spirals. Explanation: Luminosity. The rare giant ellipticals, such as M87, are more luminous than any known spiral.
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Below is a photo of M87; the light in the upper left is of the stars that make up the galaxy, while what you see extending away from that light towards the lower right is a jet of matter ejected from the galaxy, possibly due to a black hole: Elliptical galaxies range in size from the giants (such as M87 mentioned in the last question) to __________, which are believed to be the most common kind of galaxy. Explanation: Dwarfs. There are so few bright stars in this type of galaxy that even its central regions are transparent. The total number of stars, however, may be as many as several million. Below is a pic of M110, a dwarf elliptical galaxy and the last object to be added to the Messier catalog:
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About three percent of the brightest appearing galaxies in the northern sky are classified as _____________. Explanation:
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The of the stars depend upon the gravitational attraction...

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