For the first time ever, scientists have successfully managed to analyse the atmospheric composition of a distant super-Earth in great detail. Using incredibly advanced observation and processing technologies, a team of European astronomers has detected substantial traces of hydrogen and helium in the atmosphere of 55 Cancri e, an exoplanet located over 40 light-years away from Earth. Calculations of its mass and radius has revealed the presence a carbon-rich interior, which is why it is also known as the “diamond planet”.
Believed to be the most common planetary type found in our galaxy, super-Earths are a type of extrasolar planet with mass much larger than that of Earth. 55 Cancri e or “Janssen”, for instance, is nearly eight times heavier than Earth, and orbits around the star 55 Cancri, which is also referred to as the “Corpenicus” of the Cancer constellation. Being really bright, the star actually made it easier for the researchers to gather information about the neighboring exoplanet. Speaking about the find, Angelos Tsiaras, a research student at University College London and a member of the team, said:
This is a very exciting result because it’s the first time that we have been able to find the spectral fingerprints that show the gases present in the atmosphere of a super-Earth. Our observations of 55 Cancri e’s atmosphere suggest that the planet has managed to cling on to a significant amount of hydrogen and helium from the nebula from which it formed.
While the Hubble Space Telescope has been used to study the atmosphere of super-Earths on two previous occasions, the current research marks the first time that scientists have managed to analyse the specific spectral features of such an exotic celestial body. Using Hubble’s Wide Field Camera 3 (WFC3), the team scanned 55 Cancri to create several distinct spectra. These observations were then combined and processed with the help of a specially-developed computer analysis technique. Professor Giovanna Tinetti of UCL added:
This result gives a first insight into the atmosphere of a super-Earth. We now have clues as to what the planet is currently like, how it might have formed and evolved, and this has important implications for 55 Cancri e and other super-Earths.
By examining the collected data, the researchers were finally able to decipher the spectral fingerprints of the super-Earth as embedded in the light emanating from the star. Because of its proximity to the parent star, 55 Cancri e has a surface temperature of over 2,000 degrees Celsius, with one year lasting only 18 hours in total. According to the scientists, the research has revealed the presence of copious amounts of hydrogen cyanide, a compound that is usually an indication of carbon-rich atmospheres. The team explained:
Such an amount of hydrogen cyanide would indicate an atmosphere with a very high ratio of carbon to oxygen… If the presence of hydrogen cyanide and other molecules is confirmed in a few years time by the next generation of infrared telescopes, it would support the theory that this planet is indeed carbon rich and a very exotic place. Although, hydrogen cyanide or prussic acid is highly poisonous, so it is perhaps not a planet I would like to live on.