Venus' atmosphere is leaking into space

Published by Adrien - 26 days ago - Other Languages: FR, DE, ES, PT
Source: Nature Astronomy

Recent data collected by the European Space Agency's BepiColombo spacecraft, on its way to Mercury during its flyby of Venus, have revealed a leakage of gases from the latter's atmosphere. Carbon and oxygen have been detected in space. This discovery could shed light on our understanding of Venus' weak magnetic characteristics.

An artistic representation of the BepiColombo mission flying by Venus.
Credit: ESA.ATG medialab

Unlike Earth, which is protected from atmospheric leaks by its intrinsic magnetic field, Venus does not have a stable magnetic field. This is due to its cooler interior which prevents the mixing of molten materials needed to create and sustain a magnetic field. Instead, exposure to the sun charges the atmosphere's atoms, which generate electrical currents, producing an unstable, Sun-dependent magnetosphere.

In August 2021, the BepiColombo probe crossed this weak, comet-shaped magnetosphere for 90 minutes to slow down and adjust its trajectory towards Mercury. The analysis of data collected during this brief passage has revealed valuable information about Venus. It appears that charged particles, or ions, are escaping from the planet. The Sun accelerates the molecules in the atmosphere to extremely high speeds, enough for these ions to escape gravity and disperse into space.

The dense and infernal atmosphere of Venus, mainly composed of carbon dioxide, also contains nitrogen and other gases in small amounts. It was already known that small quantities of oxygen were found on the night side of Venus. Recently, a team of researchers detected this same gas on the day side of the planet. These researchers also concluded that the concentration of oxygen decreases with the reduction of solar radiation.

Schematic view of planetary matter escaping through the flank of the magnetic sheath of Venus.

Understanding the loss of these molecules and the mechanisms of their escape is crucial for elucidating the evolution of Venus' atmosphere and how it lost all its water, states Dominique Delcourt, co-author of the study and researcher at the Laboratory of Plasma Physics.

The BepiColombo mission is expected to reach Mercury by the end of 2025, after a seven-year journey. Meanwhile, several robotic missions are planning to visit Venus in the next decade, including the European Space Agency's Envision probe scheduled for 2031 and NASA's DAVINCI and VERITAS missions, both also planned for 2031 after delays.
Page generated in 0.198 second(s) - hosted by Contabo
About - Legal Notice - Contact
French version | German version | Spanish version | Portuguese version