Evidence has accumulated in recent years to show that this was not always the case. Venus might have been habitable once upon a time while it was not so old, with a beautiful climate and even liquid oceans. Maybe this is not true. According to a recent study that simulates the climates of Venus and Earth in their early years, this planet would never have cooled adequately to allow water to condense into a liquid.
Oceans have existed on Earth for approximately four billion years, while lakes and rivers existed on Mars 3.5–3.8 billion years ago. However, it is still unknown if water has ever condensed on Venus’s surface because the planet, which is currently entirely dry, has experienced overall resurfacing processes that have covered most of its history. The requirements for water to have first formed on the surface of these terrestrial planets are very unlikely. They have only been analyzed with climate models that do not include the effects of atmospheric circulation and clouds, which are important climate stabilizers.
It appears that it always has been a poisonous planet. In many regards, Venus is similar to Earth. It’s the same size and composition as the Sun, and it should have had a more moderate temperature once upon a time when the Sun was younger and colder.
It is moderate right now. Venus’s sky is dense with sulfuric acid clouds, and its atmospheric pressure at zero altitudes is almost 100 times greater than Earth’s. Even the average surface temperature is 471 degrees Celsius, which is hot enough to melt land.
However, because of the parallels between the two planets, specialists believe Venus may be a future self of what is to come for Earth as the Sun’s light continues to grow. This is particularly important if Venus was previously more like Earth, with liquid seas. But the earlier study has discovered indications that this might be true, especially when the Sun was approximately 30% dimmer than it is now.
Clouds may have developed on a newborn Venus, according to the team’s climate modeling, but only on the planet’s cooler night side. This would not only have limited solar energy from reaching the dayside, but it would also have made the planet warmer by creating a vital greenhouse effect on the night side.
This means that water vapor could never have condensed in the atmosphere, never alone in large enough amounts to rain down on the globe and fill whole seas over the years. This confirms the steam Venus concept, which was initially presented in 2013 using simpler modeling.
The research found that rather than freezing a liquid Earth, the dim early Sun would have let our hot planet cool enough to allow water to condense into a liquid. However, how Earth and Venus got up on such different evolutionary paths is a problem that planetary scientists would want to deal with. Even if it has no outcomes for our future, it may help in the discovery of more habitable worlds in the Milky Way galaxy.
The findings are based on theoretical models and represent a major step toward dealing with the question of Venus’s mystery. However, they will not be able to make a final decision on the subject using our computers. The observations of the three forthcoming Venus space missions will be crucial in confirming or denying their findings.