McMurdo Station, Ross Island, Antarctica, as seen from the radar dome at the top of the hill behind the station on January 22, 2017. This view is to the south, with Observation Hill, at 750 feet tall, in the middle distance. White fuel storage tanks are located at the base of the hill. The flat white to the right of the hill is the annual sea ice of McMurdo Sound. #

An emperor penguin, the largest of all penguins, stands proudly on the McMurdo Ice Shelf with Mount Erebus in the distance on January 23, 2017. Mount Erebus is the southernmost active volcano on Earth. #

Holy Trinity Church stands illuminated at Russia's Bellingshausen Station on King George Island in Antarctica on February 1, 2015. Holy Trinity is the world's southernmost Eastern Orthodox church and doubles as a light beacon for incoming ships. #

A Commerson's dolphin or "panda dolphin" follows the research vessel Laurence M. Gould as it travels down the Strait of Magellan on its way to Palmer Station across the Drake Passage on March 20, 2015. #

A section of the West Antarctic Ice Sheet with mountains poking through, viewed from a window of a NASA Operation IceBridge airplane on October 28, 2016, in flight over Antarctica. NASA's Operation IceBridge has been studying how polar ice has evolved over the past eight years and was flying a set of 12-hour research flights over west Antarctica at the start of the melt season. Researchers have used the IceBridge data to observe that the West Antarctic Ice Sheet may be in a state of irreversible decline directly contributing to rising sea levels. #

The Dark Sector Lab at Amundsen-Scott South Pole Station is home to the South Pole Telescope, left, and BICEP-3 experiments. Both telescopes are using the leftover glow (called the cosmic microwave background) from the Big Bang, to study the early evolution of the universe. Photographed on December 24, 2015. #

The Milky Way shines above in the night sky near McMurdo Station on June 6, 2016. Below is the site of the NASA Near Earth Network satellite dish, known locally as the "golf ball," which is one of three U.S. space communications networks collecting data from polar-orbiting satellites. In the distance on the right is a science project called SuperDARN (Super Dual Auroral Radar Network), which monitors the highest layers of the Earth’s atmosphere. It is one of several science projects that is maintained through the winter at McMurdo. #

Inside the “golf ball” overlooking McMurdo Station, NASA’s large radio dish receives data and telemetry from numerous polar-orbiting satellites. Photographed on January 22, 2017. #

A 757 jet on McMurdo's Pegasus Ice Runway is distorted by a Fata Morgana mirage on March 23, 2016. This optical illusion is caused by a layer of warm air above the cold surface. In this image the tail of the jet is connected to an inverted image of the same aircraft. #

Mountain peaks are seen from NASA's Operation IceBridge research aircraft above the Antarctic Peninsula region, on November 4, 2017. According to NASA, the current mission targets "sea ice in the Bellingshausen and Weddell seas and glaciers in the Antarctic Peninsula and along the English and Bryan Coasts." The National Climate Assessment, a study produced every four years by scientists from 13 federal agencies of the U.S. government, released a stark report on November 2 stating that global temperature rise over the past 115 years has been primarily caused by "human activities, especially emissions of greenhouse gases." #

The skeleton of a Humpback whale lies in front of the Comandante Ferraz base in Antarctica on March 10, 2014. The skeleton was placed by French researcher and scientist Jacques Cousteau in 1972 as a memorial against the killing of this species in the 20th century. #

Passengers aboard the National Science Foundation research vessel Nathaniel B. Palmer observe auroras in the winter sky. The ship was in the Ross Sea on a winter cruise on May 20, 2017. #

Tourists run to bathe in the hot springs of the crater lake on Deception Island, Antarctica, on March 6, 2016. The Antarctic tourism industry is generally considered to have begun in the late 1950s when Chile and Argentina took more than 500 fare-paying passengers to the South Shetland Islands aboard a naval transportation ship. #

The Aurora Australis and the Milky Way shine over Black Island in the middle of winter, on July 9, 2016. Black Island is a telecommunications facility that provides internet, phone, and television services for McMurdo Station, about 25 miles away. #

Two United States Antarctic Program participants conducting a glacier search and rescue (GSAR) drill on top of Detrich Island, near Palmer Station, Anvers Island, Antarctica, on April 11, 2016. #

As the Antarctic Impulsive Transient Antenna (ANITA) rests on its launch pad during a “hang test,” scientists and technicians check to see that its communications systems are working on November 23, 2016. It circled the continent on a balloon listening for the radio signals made when a neutrino strikes the nucleus of a water molecule. NASA’s Long Duration Balloon facility at McMurdo Station is used to launch scientific payloads on super pressure balloons more than 100,000 feet into the air. #

The Boron And Carbon Cosmic Rays in the Upper Stratosphere (BACCUS) balloon payload lifts off from the ground, suspended under a super pressure balloon on November 29, 2016. The scientific payload circled the continent, suspended on a balloon more than 100,000 feet in the air, studying cosmic rays. #

Diver Steve Rupp looks up through a hole in the sea ice while testing a new scuba rebreather system on October 21, 2016. Rupp and other divers are testing to see how well various rebreather systems work in the frigid waters in McMurdo Sound. #

A whale exhales air through its blowhole on March 19, 2016. Ari Friedlaender, from Oregon State University, studies the foraging behavior of whales in in the Antarctic Ocean as part of the National Science Foundation's Long Term Ecological Research program. #

An Adelie penguin catches some crashing waves as it returns to shore after feeding in the waters off Cape Crozier on January 27, 2017. The penguin colony there is one of the largest known Adelie penguin colonies in the world, home to roughly half a million birds. #

A "nunatak," or mountain peak that projects through ice, stands alone in a vast plain of ice and snow, seen from NASA's Operation IceBridge research aircraft above Antarctica on November 3, 2017. #