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There are dark regions with numerous craters called impact craters and they cover one-third of the moon. The remainder of the moon is covered by lighter regions which have many ridges and grooves . The ridges are as high as 2000ft and stretch for thousands of miles.</span>
<span>The answer is Due to heating of the air by the engine exhaust. Contrails are formed when the hot exhaust of the plane engines is rapidly cooled by the cold air in the upper atmosphere. The water vapor in the engine exhaust, formed in the combustion of fuel, freezes immediately to ice crystals due to the low pressure and -36oC temperatures in the 8000 m altitude in which the planes cruise. </span>
Well there are many but the surface of the earth is the material violin one outer core (if that makes sense
49 Kelvin = -224.15 Celsius
I believe this is the answer.
