WASP-127b: Puffiest Alien World Has A Cloud-Free Atmosphere
Recently, scientists have conducted spectroscopic studies of the alien world WASP-127b. It is the puffiest "super-Neptune" known so far.
The latest study is presented in a paper published on arXiv.org on May 25. It shows that the alien planet, WASP-127b, has either a partially or completely cloud-free atmosphere.
WASP-127b is publicly revealed in 2016. The alien world orbits around the host star called WASP-127 every 4.2 days. It is classified as "super-Neptune" with a mass of about 0.18 Jupiter mass. Because of its quite large radius of 1.37 Jupiter radii, this alien world is the puffiest known to date. It has the lowest density "super-Neptune" planet discovered so far.
The exoplanet is located approximately 332 light-years away from the planet Earth. Due to its relative proximity and the star's brightness, as well as its short orbital period, this alien world has become an excellent subject for atmospheric follow-up observations.
According to Phys.org, such studies are very important to learn new insights about the planet to explain why WASP-127b is so puffy. Studying the exoplanet's atmospheric composition could give hints at the nature of its bizarre puffiness and evolutionary history.
This is the reason that a team of astronomers from the University of La Laguna, Santa Cruz de Tenerife, Spain, has carried out spectroscopic studies of the exoplanet. The team is led by Enric Pallé. He and his colleagues use the Andalucia Faint Object Spectrograph and Camera (ALFOSC) for this study. The spectrograph is mounted at the 2.5-meter Nordic Optical Telescope (NOT) at Roque de los Muchachos Observatory.
The team of astronomers uses this resource in February 2017 to study a long-slit, low-resolution spectroscopic time series while there was a planetary transit, as well as to get the initial transmission spectrum for the alien world.
"At the bluer wavelengths, the spectrum shows a decreasing slope with λ, which seems to indicate the presence of Rayleigh scattering. A hint of Na absorption is seen (although statistically insignificant), with the band centered on the Na doublet presenting a larger planet to star radius ratio value than the surrounding bands," the astronomers revealed in the published study. Thus, the results hint that WASP-127b has a cloud-free atmosphere.