Venus is often described as Earth’s twin, but with a runaway greenhouse effect from excessive carbon dioxide. The planet closely resembles Earth in size, mass, chemical makeup, and distance from the sun. Those components, combined with the kinds of geological formations associated with water erosion, led scientists to hypothesize that Venus was once home to giant oceans, much like Earth.
Now, new research adds just one more strange, extreme phenomenon to Venus’ litany—the planet once had oceans of liquid carbon dioxide.
Already researchers suspected that Venus’s atmosphere once held an abundance of water — enough to cover the planet in an ocean 80 feet deep. But it wouldn’t have been cool enough for the clouds to release their water as rain. Instead, carbon dioxide might have gathered on the surface, scientists say in a report published in the Journal of Physical Chemistry Letters.
Carbon dioxide is common on Venus. “Presently, the atmosphere of Venus is mostly carbon dioxide, 96.5 percent by volume,” said lead study author Dima Bolmatov, a theoretical physicist at Cornell University in Ithaca, New York.
Besides Venus’ ocean being made of carbon dioxide, it may have had “a bubble of gas that is covered by a thick layer of liquid.”
So Venus “looked like soap bubbles.” He further explained that million of years ago, the combining of the hot weather and atmospheric pressure produced a “supercritical” state capable of dissolving materials like a liquid but flow like gas.
“The atmospheric pressure on the surface of Venus is currently more than 90 times that of Earth, but in the early days of the planet, Venus’ surface pressure could have been dozens of times greater. This could have lasted over a relatively long time period of 100 million to 200 million years. Under such conditions, supercritical carbon dioxide with liquidlike behavior might have formed.”
As a result, Bolmatov said that it is “plausible” that geological features such as rift valleys, river-like beds and plains on Venus are “the fingerprints of near-surface activity of liquid-like supercritical carbon dioxide.” Furthermore, they found that, depending on the pressure and temperature, gas-like supercritical CO2 clusters resembling soap bubbles may also have formed.
Bottom lin: Venus is the second planet from our sun and our closest neighbor, significantly nearer to us than Mars. It takes 224.7 Earth days to orbit the sun, and is the brightest natural object that can be seen in the Earth’s night sky. Its similar size, gravity, and composition cause it to be often referred to as Earth’s “sister planet.”
Venus’ surface temperature is a mean of 863 degrees Fahrenheit, making it the hottest planet of the Solar System — even greater than that of Mercury, the closest planet to the sun, which reaches up to 800 degrees Fahrenheit but has a mean temperature of only around 150 degrees.