Nasa scientists create temperature map of a super-earth 40 light years away
01 Apr 2016
Observations from NASA's Spitzer Space Telescope had led to the first temperature map of a super-earth planet - a rocky planet nearly twice the size of our earth.
From the map, it appears that the planet is subject to extreme temperature swings from one side to the other, and a possible reason could be the presence of lava flows.
''Our view of this planet keeps evolving,'' said Brice Olivier Demory of the University of Cambridge, England, lead author of a new report appearing in the 30 March issue of the journal Nature. ''The latest findings tell us the planet has hot nights and significantly hotter days, clarksvilleonline.com reported.
This indicates the planet inefficiently transports heat around the planet. We propose this could be explained by an atmosphere that would exist only on the day side of the planet, or by lava flows at the planet surface.''
The super-earth 55 Cancri e is 40 light-years away from earth and orbits very close to its star, going around it every 18 hours. Due to the planet's proximity to the star, it remains tidally locked by gravity much like our moon is to earth.
This meant one side of 55 Cancri, referred to as the day side, was always subject to intense heat of its star, while the night side which remained in the dark and was much cooler.
''Spitzer observed the phases of 55 Cancri e, similar to the phases of the moon as seen from the Earth. We were able to observe the first, last quarters, new and full phases of this small exoplanet,'' said Demory. ''In return, these observations helped us build a map of the planet. This map informs us which regions are hot on the planet.''
With the help of Spitzer Space Telescope Infrared Array Camera, the researchers found that the planet's nightside temperature was around 1,107 degrees Celsius while its dayside temperature was about 2,427 degrees Celsius, which meant a dayside/nightside difference of a stunning 1,027 degrees Celsius. Such a large fluctuation led to some rather bizarre conditions on the surface.
The researchers detected a peculiar hot spot on the surface located 41 degrees east from the substellar point. Scientists say this could be due to molten lava on the surface of the planet's dayside. At 2,427 Celsius, silicate-based rocks (which are common on 55 Cancri e) could be quite viscous, so this melted rock was probably flowing like water did at room temperature.