Comet Lovejoy Pass Viewed From International Space Station
The crew of the International Space Station enjoyed a front seat view of the Lovejoy Comet
as they flew over the Southern Hemisphere. The Expedition 30 crew captured video footage of the comet from aboard the space station as part of Crew Earth Observations
. Astronaut Dan Burbank described the sight as, "the most amazing thing I have ever seen in space."
The sequence of images were taken from Dec. 21 to 26, 2011. A video montage
is available online, which shows a series of five views of the comet from different perspectives from around the Southern Hemisphere. The Lovejoy Comet featured in the video passed by the Sun around Dec. 16 and was visible over the Southern Hemisphere and several South Pacific island nations.
Within the montage, the first video is from just west of South America, looking east from the Pacific Ocean. The second video was taken from southeastern Philippines to eastern Queensland, Australia. In the third video, the astronauts captured the Lovejoy Comet with a new infrared camera aboard station, which is why the video has a red tint. The images in the third video were taken from the far southern points of the Indian Ocean, northwest of the Kerguelen Islands, northeast to Malaysia. The fourth video was taken over Madagascar while the space station traveled southeast. The bright orange and yellow colors near the Earth on the bottom of the video is light from the Sun being distorted by our atmosphere. The last video was taken on Dec. 21, one of the first nights the comets could be seen from Earth as the station cruised southeast from northeast Australia to New Zealand.
The comet, officially designated C/2011 W3, or Lovejoy, was discovered by Australian amateur astronomer Terry Lovejoy on Nov. 27, 2011. It belongs to a group of comets known as Kreutz sungrazers, which are thought to be pieces of a much larger comet that broke up centuries ago but maintain the same orbit. They are termed sungrazers as their orbits take them near to the Sun, where radiation and the solar wind interact with the icy comet nuclei to produce striking visual displays of halos and tails.
Green and yellow airglow also is visible paralleling the Earth's horizon line, or limb, throughout much of the sequence before being overwhelmed by the light of the rising Sun. Airglow is the emission of light by atoms and molecules in the upper atmosphere when they are excited by ultraviolet radiation. Small intermittent flashes of brilliant white light visible over the Earth's surface are lightning discharges as seen from above, while less intense and constant lighting patterns indicate the presence of cities and towns.
by Melissa Dawson and William L. Stefanov
NASA's Johnson Space Center