Answer the following questions : (c ) Optical and radiotelescopes are built on the ground but X-ray astronomy is possible only from satellites orbiting the earth. Why?

Answer the following questions : (c ) Optical and radiotelescopes are

1.	Answer the following questions : (c ) Optical and radiotelescopes are built on the ground but X-ray astronomy is possible only from satellites orbiting the earth. Why?
Answer» Solution :In optical and radio-telescopes we use visible light and radiowaves, respectively, which can pass through atmosphere. Hence, such telescopes are built on the ground. However, X-rays haveextremely SMALL WAVELENGTHS and are absorbed by the atmosphere. Hence, X-ray astronomy is not possible from ground stations. X-ray astronomy is possible only from satellites ORBITING the earth at a height of 500 km or more.

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Answer the following questions : (c ) Optical and radiotelescopes are built on the ground but X-ray astronomy is possible only from satellites orbiting the earth. Why?

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