Thread by @weatherindia

#Venus Isn’t Habitable Today, and It May All Be #Jupiter’s Fault: Study

weather.com/en-IN/india/sp…

(📸: JAXA/ISAS/DARTS/Damia Bouic)

By @kun5k

In early September 2020, potential indicators of life were discovered on #Venus, when scientists detected the presence of phosphine on its clouds.

However, as of now, #Earth’s sister planet remains a world that is not conducive to life as we know it, and the biggest planet in our #solarsystem might be the one to blame for this shortcoming.

#Jupiter, which is two-and-a-half times more massive than all the other planets in our solar system combined, and voluminous enough to fit 1,321 Earths inside it, possesses the ability to disturb other planets’ orbits around the Sun.

In fact, it is believed to have done just that during the early period of its formation, when it gravitated towards the Sun and then moved away, until it got to its current position.

During this post-formation migration—a phenomenon that has been observed to be a relatively...

...common occurrence in other planetary systems as well—the young Jupiter affected Venus’ orbit and ended up making it more circular.

At present, Venus’ orbit is at 0.006, which is the most circular of any planet in our solar system. However, the model indicated that a...

...billion years ago, when Jupiter migrated towards the Sun, Venus most likely had an eccentricity of 0.3.

This would have made its orbit elliptical—similar to that of the Earth’s—thereby increasing the likelihood of Venus being a habitable world.

In fact, as per the study’s estimates, the change in the young Venus’ orbit is likely to have increased its water-loss rate by at least ~5%.

The variations in eccentricity may also have accelerated its atmospheric evolution, speeding-up the inevitable collapse of the atmosphere into a runaway greenhouse state that we see today.