Earth's infernal twin 'Venus' could unlock secrets of life in Universe

Imagine a world hotter than molten lead, shrouded in choking clouds of sulfuric acid, and under a relentless barrage of sunlight. This isn't a scene from a dystopian sci-fi movie, it's Venus, our closest planetary neighbour and Earth's twin sister. However, a new study published in Nature Astronomy argues that despite its infernal appearance, Venus holds vital clues to the potential for life on other planets in the Universe.

Venus and Earth are roughly the same size and mass and formed around the same time from the swirling disk of dust and gas that birthed our solar system. Yet, their evolutionary paths diverged dramatically. While Earth represents a haven for life, Venus resembles a scorching inferno. Understanding why these planetary neighbours, born from the same cosmic cradle, took such drastically different paths could be the key to identifying planets with the potential to support life beyond our solar system.

The paper published in the journal Nature Astronomy takes a deep dive into the similarities and stark differences between Earth and Venus. 

"One of the main reasons to study Venus is because of our sacred duties as caretakers of this planet, to preserve its future. My hope is that through studying the processes that produced present-day Venus, especially if Venus had a more temperate past that’s now devastated, there are lessons there for us. It can happen to us. It’s a question of how and when," says UC Riverside astrophysicist and paper first author Stephen Kane.

The runaway greenhouse suspect

The leading theory for Venus's hellish state points towards a runaway greenhouse effect, which suggests that the planet received too much solar radiation, causing its atmosphere to trap heat in a vicious cycle. This trapped heat would have caused the planet's oceans to boil away, leaving the surface parched and devoid of liquid water - a key ingredient for life as we know it. Additionally, the intense heat would have triggered a series of catastrophic events, further altering the planet's climate and solidifying its status as a barren wasteland.

"If you consider the solar energy received by Earth as 100%, Venus collects 191%. A lot of people think that’s why Venus turned out differently. But hold on a second. Venus doesn’t have a moon, which is what gives Earth things like ocean tides and influenced the amount of water here," Kane explained.

Beyond the surface

While the surface of Venus might be a no-go zone for life as we know it, there's still a lot we don't know about the planet's interior and its history. Here are some of the burning questions scientists are eager to answer:

• What's the size and composition of Venus's core?
• Venus rotates incredibly slowly compared to Earth. Why is this so, and how did it affect the planet's evolution?
• Did Venus ever have a strong magnetic field like Earth?
• What is the chemistry of Venus's lower atmosphere?

This information is crucial for understanding the planet's climate history.

"Venus doesn’t have a detectable magnetic field. That could be related to the size of its core. Core size also give us information about how a planet cools itself. Earth has a mantle circulating heat from its core. We don’t know what’s happening inside Venus," Kane said.

Preparing for the Future

Studying Venus can provide valuable insights into how planets evolve and the delicate balance needed for life to exist and thrive. Examining the factors that led Venus down its scorching path can help identify potential red flags on planets orbiting distant stars. Understanding the evolutionary path of the deadly planet can equip us with a better framework for assessing the potential habitability of exoplanets - planets outside our solar system.

Furthermore, studying Venus can help us understand the potential future of our planet. The runaway greenhouse effect is a serious concern for Earth, with scientists warning about the consequences of rising global temperatures and the potential for a tipping point. Understanding how the runaway greenhouse effect unfolded on Venus could help us develop strategies to mitigate its effects here on Earth. 

Upcoming missions

The good news is that NASA has two exciting missions planned for Venus which could be a game-changer in our understanding of the planet.

• DAVINCI+ mission will study the origin, evolution, and present state of Venus in unprecedented detail from near the top of the clouds to the planet’s surface and look for past signs of habitability.
• VERITAS mission will discover the secrets of a lost habitable world on Venus, gathering data to reveal how the paths of Earth and its twin sister diverged.

Venus may be an extreme and seemingly lifeless world, but it offers a wealth of information waiting to be discovered. By studying this infernal twin, we can unlock secrets about the delicate balance that fosters life and prepare for the future of our own planet. The scorching surface of Venus might not be hospitable, but the knowledge it holds could be the key to finding life beyond our home.