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)

Colombian Jahn Fredy Duque, dressed as superhero “Spiderman”, performs on the streets in Bogota, Colombia on April 24, 2017. Duque hangs a white cloth 26 meters long – his cobweb – from a bridge near the international center of Bogota, where he performs in the street for a livelihood. (Photo by Raul Arboleda/AFP Photo)

Bridegrooms pose for a photograph as they attend a mass wedding ceremony at Arena Corinthians soccer stadium in Sao Paulo, Brazil, September 26, 2015. According to the event's organizers, at least 400 couples tied the knot during a mass wedding which was organized by the Department of Justice and Citizenship of the state of Sao Paulo. (Photo by Paulo Whitaker/Reuters)

Trainees of the Tianjiao Special Guard/Security Consultant bodyguard training camp watch their instructor use a scarf to cover a student's head during a demonstration of close-quarter combat skills at a special course on flight safety inside a scale model of a passenger jet at a flight attendant training centre on the outskirts of Beijing, March 18, 2014. Inspired by the missing Malaysia Airlines Flight MH370, the company wanted to emphasize the importance of aviation safety by teaching their trainees emergency evacuation procedures and close-quarter combat skills to handle situations such as natural disasters and plane hijacks, according to the company. (Photo by Jason Lee/Reuters)

The Zhangjiajie National Forest Park is a unique national forest park located in Zhangjiajie City in northern Hunan Province in the People's Republic of China. It is one of several national parks within the Wulingyuan Scenic Area.

Kevin Russ, a photographer & image moderator for iStockphoto, grew up in Arroyo Grande, California. In 2003, he made the move to Portland, planning to study at Multnomah Bible College. Finding the workload to be minimal, Kevin invested in a camera, filling his free time and finding himself instantly smitten with the craft. A year and a half later, photography had evolved into his full-time job. However, after 4 years of consistent portrait work, Kevin became burnt out and took a step back from photography altogether. Two years later, he picked up the camera again and now spends the majority of his time on the road, exploring & photographing the rustic landscapes & wildlife he encounters.

Some foods have significantly more Calories than others but what does the difference actually look like. Each of the photographs below represents 200 Calories of the particular type of food; the images are sorted from low to high calorie density. When you consider that an entire plate of broccoli contains the same number of Calories as a small spoonful of peanut butter, you might think twice the next time you decide what to eat. According to the U.S. Department of Agriculture, the average adult needs to consume about 2000 - 2500 Calories to maintain their weight. In other words, you have a fixed amount of Calories to "spend" each day; based on the following pictures, which would you eat?