GK
THE UNIVERSE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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astronomical units (AU)
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kilometers (km)
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lightyears (LY)
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nanometers (nm)
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Detailed explanation-1: -The astronomers usually use light-years to measure the distance between stars. A light-year is a distance of light that can travel in one year. The astronomers also use parsec . One parsec is equal to 3.3.
Detailed explanation-2: -The light travels at a speed of 3×108 meters per second and one light year = 9.46×1012 km. The appropriate unit for measuring the distance of stars from the earth is lightyears.
Detailed explanation-3: -The average distance between galaxies is about one million light years. There are roughly 100 billion galaxies in the observable universe. Another, often-used unit of distance is the parsec. One parsec is approximately 3.26 light-years.
Detailed explanation-4: -It is not convenient to express such a large distance in the units of km. So, the distance of stars from the earth is expressed in light years. One light year is the distance that light travels in one year in a vacuum. It measures about 9.5 trillion kilometres.