A leopard skin burns as Indian officials and activists burn wildlife contraband including tiger and leopard skins, and bones as part of a campaign to save the tiger in Mumbai, India, Tuesday, July 30, 2013. Despite conservation efforts, tiger numbers in India have declined due to rampant poaching of the cats for their valuable pelts and body parts that are highly prized in traditional Chinese medicine. (Photo by Rafiq Maqbool/AP Photo)

Northern lights (Aurora borealis) glow brightly over an Inupiaq fish camp along the arctic coast in North Slope, Alaska. (Photo by Steven Kazlowski/Barcroft Media)

An alert-looking Maine Coon during the Grand Prix Royal Canin cat exhibition in Moscow, Russia on December 4, 2016. The breed’s origin is unknown, but one legend claims it is descended from cats brought to the US by an English seafarer called Captain Coon. (Photo by Dmitry Serebryakov/TASS)

Four pillars of light from the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) are shown reaching into the Chilean night sky in this image from ESO Photo Ambassador Fred Kamphues, on September 2, 2016. The lasers are a key part of the adaptive optics system on the VLT. Adaptive optics allows astronomers to drastically reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT. (Photo by F. Kamphues/ESO)

These stunning images capture some of America's most intense storms from an extraordinarily close perspective. Here: A tornado storm is rolling over the town of Stratford, Texas on May 17, 2016. (Photo by Maximilian Conrad/Caters News)

This restroom on the rubbly flanks of Jonsknuten in Norway looks up at the peak of the 904m mountain. Yu have to leave the door open to enjoy the view but the chances of being disturbed are minimal. (Photo by Olaf Menz/Lonely Planet)

A flock of sheep huddles together while snow spindrift is whipped up by strong winds in Swaledale, North Yorkshire, UK on March 17, 2017. (Photo by Paul Kingston/NNP North News & Pictures Ltd)

M42 Subtle V1 cropped. One of the most well-known astronomical objects in our universe is the Orion Nebula and this image depicts the wider region of the Orion Molecular Cloud Complex that is its home. This complex also includes another popular target for astrophotographers, the Horsehead Nebula, as well as Barnard’s Loop and the Running Man Nebula, which can be seen to the left of this photograph. (Photo by Patrick Gilliland)