GK
SOLAR SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The amount of time it takes the Sun to rotate around the galaxy.
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The amount of time it takes a celestial body to rotate around its axis once.
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The amount of time it takes to get to Mars from Earth.
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The amount of time it takes to the Moon to orbit the Earth.
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Detailed explanation-1: -That is called a solar day. Another way to measure a day is to count the amount of time it takes for a planet to completely spin around and make one full rotation. This is called a sidereal day. On Earth, a sidereal day is almost exactly 23 hours and 56 minutes.
Detailed explanation-2: -Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes and 4 seconds with respect to other distant stars (see below). Earth’s rotation is slowing slightly with time; thus, a day was shorter in the past.
Detailed explanation-3: -The Sun rotates on its axis once in about 27 days. This rotation was first detected by observing the motion of sunspots. The Sun’s rotation axis is tilted by about 7.25 degrees from the axis of the Earth’s orbit so we see more of the Sun’s north pole in September of each year and more of its south pole in March.
Detailed explanation-4: -The Earth’s axis runs from the North Pole to the South Pole. It takes the Earth 24 hours, or one day, to make one complete rotation around this invisible line.