Sometimes,observers see this as a comet's tail, which can be visible to the unaided eye stretching across the night sky.

VOA: special.2011.02.09

And BP's chairman told Sky News that Tony Hayward will no longer be supervising the daily operations in the Gulf of Mexico.

VOA: special.2010.06.19

Max Arthur Cohn's painting "Coal Tower" shows the dark form of a coal tower against a light sky.

VOA: special.2009.03.23

She's cocoa brown with the red undertones. She's got the night sky in her eyes, but she wears glitter shirts so she can shine.

VOA: special.2009.04.27

The curving brushstrokes of Van Gogh's expressive sky look like explosions of blue fire.

VOA: special.2010.03.24

Hubble watched the night sky with instruments at the university's Yerkes Observatory.

VOA: special.2009.04.29

Its arch, reaching 106 meters into the sky, recalls the national flag and has changed the city's skyline.

VOA: standard.2010.06.02

Beijing's night sky was lit up by thousands of exploding fireworks to scare off evil spirits.

VOA: standard.2010.02.14

The sky's the limit." "It's a clean,renewable, highly efficient form of propulsion."

VOA: standard.2010.08.11

And he pledged his support for the agency. "We expect that there's,as we speak, another generation of kids out there who are looking up at the sky and are going to be the next Armstrong, Collins and Aldrin,".

VOA: standard.2009.07.20