When does summer end? The calendar tells us one thing, but astronomy tells us something else. See how meteorologists officially determine the end of summer.
What's perfect swimming weather? Check out what most people consider comfortable air temperatures and water temperatures for swimming -- then break out your goggles and snorkel!
The outer layer of our atmosphere (the exosphere) is a mysterious place between the atmosphere & outer space. See how high up it is & how scientists tell where outer space begins.
Fair weather cumulus clouds form when the weather is stable & good. These puffy white clouds mean its safe to go out and enjoy the outdoors w/o the risk of bad weather
