Estivation is the summer equivalent of hibernation, a period of torpor during hot weather practiced by animals that have any sense at all. When you wake on a summer morning and your eyes look like this,
it's time to estivate. Ok, my illustration is really a photo of the moon I took through a telescope and framed in a big knothole --but it's close. How close?
That question brings us to the next photo, the pumphouse thermometer out back. This is how it's looked for a week:
The moon keeps about 240,000 miles from our planet, and has done so for 4 billion years. The sun, however, is not satisfied with that and varies its distance. I'm too hot to pore through my astronomy book for exact data, but I guess I know a thing or two about thermometers. The good ones are graduated in both Fahrenheit and Celsius so we can calculate our solar remove.
Here's how: 1st, divide the Fahrenheit scale by the Celsius scale; 2nd, label the quotient in miles. That's it. Pumphouse thermometer reads about 112F and 45C. Therefore the sun is only about two and a half miles away right now.
You don't want the sun too close. Life there is hard. There's a kind of fish --made of titanium and asbestos-- that glows red and transparent in the sun's heat and swims over oceans of fire, but less adaptable creatures must content themselves with family generations that only span 1 billionth of a second.
If there are any errors in my calculations, I shall correct them in autumn --hopefully before winter hibernation.