Astronomers using the CARMENES spectrograph have found evidence of water vapor in the atmosphere of a hot exoplanet called Saturn HD 149026 bIt was called Smertrios. A finding reported in a research paper published on the preprint server arXivIt could be the key to better understanding the structure and scenario of this alien world’s formation.

Smertrios is a hot, metal-rich, orbiting Saturn HD 149026 – a yellow subgiant star of spectral type G0 IV, approximately 248.5 light-years away. The planet has a radius of about 0.81 Jupiter radii, about three times smaller than Jupiter. Previous observations had shown that Smertrios orbits its host every 2.876 days, or about 0.043 AU from it. The planet’s equilibrium temperature is estimated to be 1693 K.

A team of astronomers led by Syed A. Rafi of the University of Tokyo in Japan employed CARMENES at the Calar Alto Observatory to perform high-resolution Smertrios cross-correlation spectroscopy. Their primary goal was to learn more about the composition of this exoplanet’s atmosphere.

“Transmission spectroscopy is one of the most successful approaches for studying exoplanet atmospheres. We obtained the high-resolution near-infrared transmission spectrum of the hot Saturn HD 149026 b with the CARMENES spectrograph.

Analyzing the CARMENES data, Rafi’s team found evidence of a water signal very close to the expected location of Deathrios. The strongest signal had a signal-to-noise ratio (S/N) of 4.8. The astronomers noted that the detected signal cannot currently be considered a confirmed detection, but only evidence of the presence of water vapor.

According to the study, evidence of water vapor in Smertrios’ atmosphere suggests that if the atmosphere is homogeneous and in chemical balance, the carbon/oxygen ratio on the planet should be less than one. Too low.

Despite searching for hydrogen cyanide in Smertrios’ atmosphere, the researchers found no evidence of the compound. Astronomers believe this may be due to the relatively low S/N dataset. Therefore, the possibility of hydrogen cyanide in the planet’s atmosphere cannot be completely ruled out.

The study also measured Smertrios’ orbital speed and resting speed, which were approximately 158.17 and 2.57 km/s, respectively. However, while the orbital speed matched the expected value, the remaining resting speed was noted to be strongly redshifted. The study authors concluded that this could be explained by several scenarios, such as anomalous dynamics of the atmosphere or an orbit with non-zero eccentricity.