If not for the fast moving atmosphere on Venus, Earth would not be rotating. Venus would be locked in place, facing the sun the same way the moon faces Earth.
A phenomenon called tidal locking occurs when the gravity of a large object in space prevents a smaller object from spinning. A scientist from UCRiverside argues that the atmosphere needs to be a more prominent factor in studies of Venus as well as other planets.
The arguments and descriptions of Venus as a partially tidally locked planet were published today in a Nature Astronomy article.
Stephen Kane said that the atmosphere is a thin, almost separate layer on top of a planet that has minimal interaction with the solid planet.
The atmosphere of Venus circulates every four days. The atmosphere drags along the surface of the planet as it circulates, causing it to slow down and loosen the grip of the sun.
The Venusian climate is hot enough to melt lead if it were not for the slow rotation.
Kane said that standing on the surface of Venus would be like standing at the bottom of a hot ocean. You couldn't breathe on it.
The heat is caused by the fact that the sun's energy is soaked up by Venus, never reaching the surface. NASA sent a rover to Mars that had solar panels, but it wouldn't work.
The Venusian atmosphere blocks the sun's energy from leaving the planet, preventing cooling or liquid water on its surface, a state known as a runaway greenhouse effect.
It is not clear whether being partially tidally locked contributes to the runaway greenhouse state, a condition which ultimately renders a planet uninhabitable by life as we know it.
It is important to understand Venus and the exoplanets that are likely to be targeted for future NASA missions.
Venus is close to the sun, but most of the planets are very close to their stars. They are also likely to be locked up.
Since humans may never be able to visit exoplanets in person, we need to make sure computer models account for the effects of tidal locking.
We are not doing a good job of considering this. Earth-type models are used to interpret the properties of exoplanets. Venus is waving both arms around.
Gaining clarity about the factors that contributed to a runaway greenhouse state on Venus can help improve models of what could happen to Earth's climate one day.
Kane said that his motivation in studying Venus was to better understand the Earth.More information: Atmospheric Dynamics of a Near Tidally Locked Earth-Size Planet, Nature Astronomy (2022). DOI: 10.1038/s41550-022-01626-x Journal information: Nature Astronomy Citation: Why Venus rotates, slowly, despite sun's powerful grip: Planet's atmosphere explains the gravity of the situation (2022, April 20) retrieved 20 April 2022 from https://phys.org/news/2022-04-venus-rotates-slowly-sun-powerful.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.