January 5, 2010
In the grand ledger of cosmic time, a human life is breathtakingly brief. But brevity is not insignificance.
A Roll Cloud Over Uruguay
Birthday · January 5, 2010
A little universe, just for you
Your date.
Ready to give.
Free PNG · 1080 × 1350 · No account needed
Image rights and credit requirements apply when sharing or reusing imagery.
Date & occasion only
Change the year
APOD published January 5, 2010. Credit: roll cloud. A publication-date match, not a photo taken on your date. Independent of NASA.
What kind of cloud is this? A roll cloud. These rare long clouds may form near advancing cold fronts. In particular, a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point, and so form a cloud. When this happens uniformly along an extended front, a roll cloud may form. Roll clouds may actually have air circulating along the long horizontal axis of the cloud. A roll cloud is not thought to be able to morph into a tornado. Unlike a similar shelf cloud, a roll cloud, a type of Arcus cloud, is completely detached from their parent cumulonimbus cloud. Pictured above, a roll cloud extends far into the distance in 2009 January above Las Olas Beach in Maldonado, Uruguay. Note: An APOD editor will review astronomy images of 2009, hosted by the Amateur Astronomers Association of New York on Friday, January 8 at the American Museum of Natural History, NYC.
Image credit: roll cloud