Pluto's 'Mysterious' Heart Finally Explained

In 2015, NASA's New Horizons spacecraft captured an image of Pluto which has gone viral on social media. The image is that of the icy planet with a big heart splashed across its surface. A year after, scientists now have an explanation for Pluto's mysterious icy heart.

The study on Pluto's heart was published in the journal Nature. The researchers used observations and data that were collected by NASA's spacecraft. They ran simulations of the last 50,000 years of Pluto's history, both in the past and into the future, to see what could have caused the icy heart and how it would change.

It was previously thought that the heart of Pluto was caused by a vast reservoir of nitrogen ice. However, there have been no reservoirs of nitrogen ice found on the planet. Instead, researchers concluded that Pluto's mysterious heart was caused by the deep basins on the planet's surface. Thanks to the incredibly cold temperature and seasonal shifts in methane, the frosted heart of Pluto appeared.

"Our knowledge of what is on Pluto's surface does not change, but we know now why it is here and not there," stated Tanguy Bertrand, a Ph.D. student at Paris' Université Pierre et Marie Curie and co-author of the study.

Another surprising discovery about Pluto's heart is that it won't likely disappear due to the seasonal frosts, but it could cause a stranger phenomenon. Pluto's heart could enlarge and shrink with time -- like that of a beating heart.

"The half heart glacier lying inside is a really massive glacier, which is not impacted by the seasonal changes. It probably formed when the basin formed, and will remain there in the future. However, it probably flows and retracts over a few hundreds of kilometers (like a heart beating) with time, eroding and shaping the mountains surrounding it," explained Bertrand.