APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Anvil Cloud Over Sicily
Explanation: The cloud poses no danger to the building. Appearing to float above a remote monastery in Sicily , Italy , the anvil cloud 's shape shows several classic cloud features. The cloud itself is composed of millions of very small droplets of water and ice . The dramatically flat cloud bottom is caused by temperature falling in the lower atmosphere -- above a specific height water-saturated air is forced to condense out water droplets. The shape of the cloud middle is caused by the water-droplet-laden column of air being blown both upward and to one side. The anvil shape at the cloud top is likely caused by the upward air column reaching a stable atmospheric layer, likely the stratosphere , where horizontally moving air fans out the top of the cloud. The cumulonimbus cloud was captured out the front door of a house last year.
| Date | February 18, 2004 |
|---|---|
| Credit | Credit & Copyright: Christina Carlton |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



