- Nasiruddin Tusi was the famous astronomer of Iran whom George Sarton attributes 64 scientific books and he also worked as scientific advisor to Halaku Khan.
 - Estimated age of the Universe is 13 billion years.
 - The first tourist in space was Dennis Tito.
 - International Date Line is mainly vertical.
 - Heat received by the Earth from the Sun is known as solar radiation.
 
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