Cirrus clouds are high-altitude clouds, often appearing as thin, wispy strands. They are usually found at altitudes above 20,000 feet and are composed mostly of ice crystals. Cumulus clouds ...

We haven’t yet figured out what gives them their shape, determines their altitude – or makes them rain when they do. What’s ...

In the years since then, balloon flight technology has evolved from cloth balloons and open baskets to polyethylene balloons and metal pressurized gondolas that allow for high-altitude atmospheric ...