Commonly known as the "dirty snowballs" of space, comets can offer some of the most spectacular sights to see in the night sky, with their luminous tails of colorful gas. Check out some of the most amazing photos of these dirty snowballs in this comet gallery.
The image above features Comet C/1995 O1 Hale–Bopp, which shone in the night sky in 1997. Long period comets such as Hale-Bopp were once deemed to be the primary impact hazard to Earth.
Related: The greatest comet close encounters of all time
Comet West
This photograph of Comet West, one of the greatest comets of all-time, was taken by amateur astronomer John Laborde. The picture shows the two distinct tails. The thin blue ion tail is made up of gases, while the broad white tail is made up of tiny dust particles.
The Streak
This gallery showcases the first images taken by NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft. Comet Siding Spring flashes across the sky impressively in this infrared image. Observers in Australia discovered the comet, also known as C/2007 Q3, in 2007.
Stunning Comet's Size Shocks Scientists
Comet McNaught over the Pacific Ocean. Image taken from Paranal Observatory in January 2007.
Comets From Edge of Solar System Unlikely to Hit Earth
A long-period comet called 2001 RX14 (Linear) turned up in images captured in 2002 by the Sloan Digital Sky Survey telescope in New Mexico.
Broken Comet On Its Way
Comet 73P breaking up in 1995.
Comet Lovejoy & Tail From Space
Comet Lovejoy is visible near Earth's horizon in this nighttime image photographed by NASA astronaut Dan Burbank, Expedition 30 commander, onboard the International Space Station on Dec. 22, 2011.
Halley's Comet in 1986
An image of Halley's Comet taken in 1986.
Solar Storms Smack a Comet
This image of comet 153P/Ikeya-Zhang, taken by skywatcher Gilbert Jones on March 11, 2002, shows its ion tail decimated by a run-in with a coronal mass ejection (CME) from the Sun.
Cosmic Stage Set for Comet Lulin Show
Jack Newton and his wife are building a stargazing community 150 miles southeast of Tucson. That Arizona Sky Village was the location from which he made this photo of comet Lulin on Feb. 18, 2009.
Christmas Comet Lovejoy
European Southern Observatory optician Guillaume Blanchard captured this marvellous wide-angle photo of Comet Lovejoy on 22 December 2011 as it appeared over Paranal Observatory in Chile.
Comet Tuttle at the End of 2007
Giampaolo Salvato photographed Comet Tuttle on Dec. 30, 2007 as it appeared near the spiral galaxy M33. The image was taken from northern Italy with a backyard telescope and a digital camera.
Comet Tempel 1 Closest to Earth
The Kitt Peak National Observatory's 2.1-meter telescope observed comet Tempel 1 on April 11, 2005, when the comet was near its closest approach to the Earth.
Comet Lovejoy Over Santiago de Chile
This beautiful dawn photo of Comet Lovejoy over Santiago de Chile was taken by ESO Photo Ambassador Yuri Beletsky on 22 December 2011 at 05:00 in the morning.
Comet Lovejoy From Space Station
International Space Station Commander Dan Burbank captured spectacular imagery of Comet Lovejoy from about 240 miles above the Earth’s horizon on Wednesday, Dec. 21, 2011.
Comet Plows into Sun After Big Solar Storm
Soon after a huge solar storm erupted on May 20-21, 2011, a comet (bright streak at lower right) plunged into the sun. This shot is a still from a video taken by one of NASA's twin STEREO spacecraft.
New Comet Now Visible to Naked Eye
Comet c/2004 Q2 (Machholz) was photographed on Sept. 14 by Gianluca Masi and Franco Mallia, as part of an educational project in Italy using the SoTIE telescope in Las Campanas, Chile.
Comet Diving Towards the Sun
As SOHO observed with its two coronagraphs for about a day (July 5-6, 2011), an icy comet flew in from behind the Sun and met its end.
Sungrazing Comet Lovejoy
Observations from NASA's Solar Terrestrial Relations Observatory (STEREO) spacecraft show the sungrazing comet Lovejoy as it approaches the sun in December 2011.
Comet Lovejoy's Tail Near the Sun
This image, taken by NASA's Solar Dynamics Observatory, shows Comet Lovejoy diving through the sun's atmosphere on Dec. 15, 2011. Lovejoy's tail is visible as a faint diagonal smudge to the left of the sun, toward the bottom of the image. The tail points from lower left to upper right.
Kapow! Comet Tempel 1 Gets Smacked
This image of Comet Tempel 1 was taken by NASA's Deep Impact spacecraft on July 4, 2005, 67 seconds after a probe crashed into the comet.