Nasa brings hot news from the Antarctic underground
The Antarctic is being melted from below, according to a new study by Nasa - and a type of buried supervolcano may be to blame.
The Nasa study adds evidence that there is powerful geothermal activity underneath the ice, creating lakes and rivers below the surface.
Three decades ago a scientist at the University of Colorado Denver suggested that heat from a "mantle plume" under Marie Byrd Land in western Antarctica might explain regional volcanic activity and the fact that the land there looks very much like a dome. Very recent seismic imaging has supported this concept.
Nasa said: "A geothermal heat source called a mantle plume lies deep below Antarctica's Marie Byrd Land, explaining some of the melting that creates lakes and rivers under the ice sheet.
"Although the heat source isn't a new or increasing threat to the West Antarctic ice sheet, it may help explain why the ice sheet collapsed rapidly in an earlier era of rapid climate change, and why it is so unstable today."
The scientists drew on changes in the altitude of the ice sheet surface, recorded by a Nasa satellite.
Separately, the data beamed back to Earth from Nasa's Voyager 1 spacecraft has been used to make a piece of music to celebrate the 40th anniversary of its launch.
The three-minute work is based on information captured by a special telescope aboard the craft, which is designed to identify protons, alpha particles, and other matter.
Scientists used data stretching back to 1977 to create a melody that follows the journey of Voyager 1.