Mysterious Super-Earth “55 Cancri e” fascinates scientists. And because recent studies show a significant temperature difference between “night” side and “daytime” of the exoplanet.
Brice-Olivier Demory astrophysicist at the University of Cambridge, and colleagues measured with the Spitzer space telescope radiation emitted in the infrared by the exoplanet 55 Cancri e , located 40 light years from Earth in the constellation of Cancer, when the latter passed its star. And the data (almost 75 hours of data spread over a month of observation, in 2013) give us some idea of hell.
Therefore, and for the first time, astronomers successfully designed a map revealing the temperature current at the surface of a super-Earth. They then found that there was a significant difference in temperature, about 1,300 degrees Celsius, between the two sides of the planet. “ From the day side, the temperature is around 2,500 ° C, while the night side, it is about 1,100 ° C, it makes a big difference ,” says especially in a statement Dr Brice-Olivier Demory .
such temperatures are not surprising, 55 Cancri e orbiting at a very small distance around its star (actually it so the turn in just 18 hours). We also know that, like the moon with the Earth, 55 Cancri e is in synchronous rotation around its star, meaning that it always presents the same face. A day side, swept away by the heat of the star, is opposed to a nightside, diving in the cold and darkness. But thanks to data provided by the telescope, we now know that the day side is significantly hotter and there would be no flow of heat between the two sides.
It is this variation temperature that puzzles scientists. Some say it is due to the lack of atmosphere, able to transport heat from one hemisphere to the other via the “winds”, while others argue that it was partially destroyed by the radiation of the star. One thing is sure is that this extreme weather has a major impact on the surface of the planet, and would have two distinct faces, one fully melted and solidified each other, as shown in the animation video below.
According to scientists, the day side could potentially present rivers of lava and large pools of very hot magma, while the night side it would have solidified lava flows (as found in Hawaii). Still, the researchers still wonder about the origin of the large temperature difference, which they can not be explained by the presence of the star.
The demonstration a contrast in temperature between two sides of a “super-earth” is nonetheless a first and paves the way for future observation of this type of celestial objects. From 2018, scientists might be able to go even further with the arrival of James Webb Space Telescope NASA supposed to succeed the Hubble Space Telescope. With a mirror of 6.5 meters, is expected to revolutionize the study of exoplanets, offering more precise observations and especially allowing astronomers to see further
Sources:. Space, Letemps
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