Answer to Question 1
FALSE
Answer to Question 2
One early idea was that the Sun shone through chemical burning (like a conventional fire on Earth), but this was discounted when the huge energy output of the Sun was first estimated. A popular hypothesis suggested in the late 1800s was that the Sun shone through the emission of thermal energy resulting from gravitational contraction. While the Sun was required to contract only slightly each year to maintain its temperature, this contraction could only last for about 25 million years, far less than the estimated age of the Earth at that time.