You probably already read the Library of Congress mystery entryLinks to an external site.. What's the question ... what's the best way to cook an egg using just the power of the sun on a nice super hot day? Group of answer choices Since an egg needs a temperature of 70 C (158 F) to firm up the proteins and get them to coagulate, you'll either need mirrors, solar reflectors, or try something other than cement ... like the hood of a carLinks to an external site.. A cement sidewalk can get hot enough (70 C), but it quickly cools off upon contact with the egg. So the trick is to polish the sidewalk to something smooth, so you can keep flipping the egg. The best answer is that its just not possible to fry an egg, even in Arizona in the summer, using just the power of the sun. Asphalt is darker and hotter than cement. So if you try to scramble an egg on asphalt, you can move it around to keep in contact with the hot surface