Using data collected by NASA's Spitzer Space Telescope, a team of astronomers have produced the first ever heat map of an Earth-like exoplanet. The alien climate map paints a grim picture of a world scorched by its close proximity to its host star, with extreme temperature variations noted between the star-facing and far side of the planet.
To describe 55 Cancri e as a "super-Earth" could be considered somewhat misleading when used in conjunction with our home planet, as the two bodies bear few reconciling traits. The planet, which boasts a mass of around eight times that of Earth in a body roughly twice the size, is incredibly inhospitable when compared to the blue marble on which we reside.
55 Cancri e is tidally locked much like our Moon, meaning that the exoplanet only ever displays one face to its parent star. The so-called super-Earth is also known to orbit very closely with its parent star, taking only 18 hours to complete a full cycle, resulting in hellish surface temperatures.
The new study drew on data collected by Spitzer over the course of 80 hours as it observed distinct phases of 55 Cancri e as it passed in front of its parent star. These phases when observed from Earth are very similar to the phases of our Moon, and allowed the astronomers to build up a global map of the unusual super-Earth detailing heat distribution and temperature changes across its surface.
NASA inforgraphic displaying the brightness of 55 Cancri e as it progressed through the various phases captured by the Spitzer Space Telescope
The map displayed a surprising disparity in heat levels between the star-facing side of the exoplanet, which experiences a blistering temperature of 4,400º F (2,700 K), and the far side, which is believed to endure around 2,060º F (1,400 K).
The study jars with previous interpretations of data that had led some to believe that 55 Cancri e was something of a water world hosting a dense atmosphere that generated powerful winds responsible for distributing heat.
Instead, the team asserts that the large difference in temperature between the star-facing and far sides of the planet act as evidence for a lack of such a system. It is possible that the star-facing side of 55 Cancri e is characterized by vast lava flows and prevalent magma pools. On the far side, the temperature drops harshly enough for the flows to solidify, preventing heat from being distributed effectively.
The notion of lava flows and pools of magma existing on the surface of 55 Cancri e are strengthened by an observed shift in the location of the hottest point on 55 Cancri e to a position directly beneath the parent star.
A paper on the study is available online in the journal Nature.