Sky Light: Biggest Solar Flare in Years
The Hubble telescope has recorded a new view of the "Necklace" nebula, the remnants of a star that aged and expanded, consuming a companion star that orbited it. In this composite image, shot on July 2, 2011, hydrogen gas is blue, oxygen is green, and nitrogen is red.
NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Celestial Sightings: What Was in the Sky?
The sun gave off the largest solar flare in five years on Aug. 9, 2011, sending a mass of charged particles into space. It was not pointed toward Earth, which is protected anyhow by its atmosphere and strong magnetic field, but scientists say the sun is becoming more active after a long quiet period.
NASA/Solar Dynamics Observatory
Sky Sightings: Eclipse, Aurora and More
Lunar eclipse of June 15, 2011, visible from Africa and Asia was shown on Google's homepage.
The upside-down rainbow, or circumzenithal arc, is a visual effect similar to normal rainbows, except that it only takes shape when the sun is lower than 22 degrees radius over the horizon.
An annular solar eclipse was seen from Qingdao, China, Jan. 15, 2010. The eclipse looks this way because the moon, in its slightly elliptical orbit, is too far from Earth to cover the sun's face completely. It is predicted to be the longest of its kind for the next 1,000 years.
A sun pillar is created when millions of falling ice crystals reflect the sun's rays, creating a column of light. They often occur at sunset or sunrise.
Ice crystals associated with cirrus clouds, diamond dust and ice fog create the effect known as sun dogs. Sun dogs happen when the sun is low and the crystals refract or reflect the sun's rays.
Norbert Rosing/National Geographic/Getty Images
As with Aurora Borealis, Aurora Australis, the southern lights seen from southern Australia, are displayed during strong geomagnetic events. In 2001, the sun sent a powerful burst of energy toward Earth, triggering dazzling aurora displays over nighttime skies. Such blasts can distort Earth's magnetic field, producing in extreme latitudes, colorful nocturnal sky displays known as auroras, or northern and southern lights.
A double rainbow is seen over the city of Baghdad on November 2, 2004. The first rains of winter came after months of dry weather.
Marwan Naamani/AFP/Getty Images
When sunlight streams through a cloud, the result is an effect known as Crepuscular rays, or God's rays. They often occur during dawn and dusk hours.
Mount Katahdin, the tallest mountain in Maine, is seen in a three-hour time exposure in February 2002. The photographic effect created by such a long exposure is known as star trails.
Robert F. Bukaty/AP Photo
Halos are bright rings that circle the sun, the moon or other bright objects such as street lights. They are typically caused by light that is reflected by ice crystals.