This morning's partial solar eclipse had the sun masquerading as a crescent moon, as seen in a picture taken through trees in Lublin, Poland.
In fact, the moon had a part to play in the celestial event—partial solar eclipses happen when the moon blocks part of the sun's disk, as seen from Earth, casting parts of the planet in shadow. This morning's eclipse was visible across most of continental Europe, North Africa, the Middle East, and Central Asia.
In some regions rainy skies blocked a good portion of the eclipse, although thinner clouds added an otherworldly effect to some peoples' views.
"It was a memorable experience and I feel lucky to [have seen] it," astronomer Gianluca Masi of Rome, Italy, told Space.com.
Photograph by Wojciech Pacewicz, European Pressphoto Agency/Corbis
Partial Solar Eclipse Progression
A series of pictures taken from Vienna, Austria, shows the moon's path as it blocked a portion of the sun during Tuesday's partial solar eclipse.
The amount of the sun that appears covered during a partial solar eclipse varies by location. Many capital cities in Europe saw at least 50 percent of the sun eaten away by the moon during today's eclipse—if clouds didn't get in the way.
The farther north observers were in Europe, the more the sun seemed to vanish. Sweden, for example, saw the maximum eclipse, with about 80 percent coverage.
Photograph by Heinz-Peter Bader, Reuters
A seagull is silhouetted against this morning's cloud-covered partial solar eclipse, as seen from a beach in Málaga, Spain.
The Tuesday eclipse was the first of four partial solar eclipses in 2011. The next eclipse of the sun will occur late on June 1, when the path of the moon's outer shadow, or penumbra, will cross Alaska, northern Canada, Siberia, and northern China.
Photograph by Jon Nazca, Reuters
Masked Eclipse Watcher
Ultra-Orthodox Jewish men use a welder's helmet (left) and a glass filter to watch Tuesday's partial solar eclipse from Jerusalem, Israel.
Viewing solar eclipses safely requires special filters on glasses, cameras, and telescopes, because looking directly at the sun without such protection can cause eye damage. Observers can also look at live images of the eclipsed sun by making simple pinhole cameras, according to eclipse expert and National Geographic grantee Jay Pasachoff.
"Just punch a hole a few millimeters across in a piece of cardboard and hold it up to sunlight, and look at the image that it casts with the sun at your back," he recently told National Geographic News.
Photograph by Abir Sultan, European Pressphoto Agency/Corbis
The Plane Truth
An airplane seems to fly past a partial solar eclipse on Tuesday, as seen from Barcelona, Spain.
In addition to partial eclipses, sky-watchers may see two other types of solar eclipses in a given year: total and annular. During a total eclipse, the moon completely blots out the sun. During an annular eclipse, the moon covers only the central part of the sun's disk, leaving a ring of sunlight still visible. (See annular eclipse pictures.)
This year is unusual, because there will be only partial eclipses: "That hasn't happened since 1982 and won't happen again until 2029," Pasachoff said.
Photograph by Alberto Estevez, European Pressphoto Agency/Corbis
Healing Solar Rays?
People bury a partially paralyzed boy in the sand along the banks of the Indus River in Pakistan during the Tuesday solar eclipse. A local physician had advised that sunlight from the eclipse would help the boy heal, according to the European Pressphoto Agency.
In nearby India superstition holds that pregnant women should avoid going outside during a solar eclipse, as it's believed that light from the eclipsed sun can cause babies to be deformed. Indians have also been told not to eat during an eclipse for fear of consuming impure foods.
Photograph by Nadeem Khawer, European Pressphoto Agency/Corbis
Light from the partially eclipsed sun filters through the clouds over Varna, Bulgaria, on Tuesday, creating a Cheshire Cat grin.
The next total solar eclipse won't happen until November 14, 2012, when the path of the moon's shadow will cross Australia and the South Pacific. Before that, on May 20, 2012, an annular eclipse will be visible from China, Japan, the U.S., and the Pacific Ocean.
Photograph by Juliano Miteff, My Shot
A man waves at the partially eclipsed sun from Lahore, Pakistan, on Tuesday.
"I was impressed to see many casual observers trying to look at the sun," Italian astronomer Masi told Space.com. "People were quite informed, I must say: Eclipses are among the things happening up there they like more."