If you think volcanoes on Earth are hot, then you haven’t heard of 55 Cancri e. The rocky exoplanet located some 40 light-years from our solar system has some truly extreme weather, and a recent map produced by astronomers at San Francisco State University shows that one half of the planet is so hot that molten rock flows like water straight to the surface.

The study was published yesterday in the journal Nature, and provides a detailed thermal map of 55 Cancri e. Despite one half of the planet being an actual sea of lava, it experiences huge temperature fluctuations between the day side and the night side.

Despite its name as a “Super-Earth,” the planet bears little similarities to our home. It’s nearly twice the size of Earth, and is the innermost planet in its solar system. It takes only 18 hours on Earth for 55 Cancri e to complete one revolution of its sun.

According to the study’s lead author, astronomer Stephen Kane, “The planet experiences a vast difference in temperature between its day and the night, so there is almost no thermal communication between the hemispheres. The best explanation for this is that the atmosphere has been completely eroded away by the energy from the star.”

55 Cancri e is the first known example of an exoplanet that exhibits such extreme weather. Kane says it offers a unique insight into how a planet’s proximity to its host star can influence the makeup of its atmosphere. On this planet, temperature during the day is a blistering 2,700 kelvin, or roughly 2,427 degrees Celsius. At nighttime, the temperature dips to a balmy 1,380 kelvin, or 1.107 degrees Celsius.

While the authors of the study believe the rapid transfer of heat energy across the surface of the planet is likely influenced by strong winds and lava flows, they believe there may be another unknown source of heat that would explain the images seen on the infrared map.

A press release describing the details of the recent study can be found here.