(Web Desk) - Gases, including oxygen, are stripping away from the upper layers of the atmosphere of planet Venus, which is important to understand how the planet lost its water, a study said.
During its journey to Mercury in 2021, the joint European and Japanese mission BepiColombo performed its second fly-by of Venus and found that carbon and oxygen ions were escaping from the unexplored region of the planet's magnetic environment, the study of which was published in Nature Astronomy journal.
"These results have important implications regarding the evolution of Venus’s atmosphere and, in particular, the evolution of water on the surface of the planet," the study stated.
Over a period of 90 minutes, BepiColombo measured the number and mass of charged particles it encountered, capturing information about the chemical and physical processes driving atmospheric escape in the flank of the magnetosheath.
Venus doesn't have an intrinsic magnetic field in its core like Earth. But, a weak, comet-shaped "induced magnetosphere" is created around the planet due to solar winds with electrically charged particles in Venus’s upper atmosphere.
The region around the magnetosphere is called the "magnetosheath", where the solar wind is slowed and heated.
Data for the study were obtained by BepiColombo’s Mass Spectrum Analyzer (MSA) and the Mercury Ion Analyzer (MIA) during its second flyby.
The two sensors are part of the Mercury Plasma Particle Experiment (MPPE) instrument package, which is carried by Mio, the JAXA-led Mercury Magnetospheric Orbiter.
The research stated that Venus was similar to Earth in many ways during its formation, including the presence of water on the planet.
"However, Venus eventually evolved in a divergent way, leading to substantial differences between the two planets. Unlike Earth, Venus is now an extremely dry planet that lacks an intrinsic magnetic field," it said.
The atmosphere of Venus, composed of carbon dioxide with small amounts of nitrogen and other gases, is affected due to solar winds, leading to outflow of important ions.
"Therefore, studying and characterising the present escape of ions from Venus is important for understanding the evolution of its atmosphere, and in particular, the evolution of water on the surface of the planet.
Such studies may also provide insights into the general climate and habitability evolution of terrestrial planets and exoplanetary systems," the study said.
Lina Hadid, CNRS researcher at the Plasma Physics Laboratory (LPP) and lead author of the study was quoted as saying by Europlanet Society, "This is the first time that positively charged carbon ions have been observed escaping from Venus’s atmosphere.
These are heavy ions that are usually slow moving, so we are still trying to understand the mechanisms that are at play. It may be that an electrostatic ‘wind’ is lifting them away from the planet, or they could be accelerated through centrifugal processes".