Newly Discovered Geological Connection Between Earth and Venus Uncovered by Scientists

Venus is often referred to as Earth’s sister planet due to their shared physical, geological, and atmospheric characteristics. Recently, scientists have made a groundbreaking discovery about Venus’ geology that further emphasizes the similarities between the two planets. To uncover this new finding, researchers delved deep into the inner workings of both Earth and Venus.

There are several reasons why Earth and Venus are likened to twins:

• They are adjacent planets in the inner Solar System.
• Both planets are rocky in composition.
• They boast similar sizes and masses.
• Both exhibit minimal cratering, hinting at relatively youthful surfaces.
• They possess atmospheres with dense cloud cover.
• They share geological features such as volcanoes, mountains, plateaus, and plains.

A recent study published in Nature Geoscience sheds light on the latter point in the list. Titled “Ishtar Terra highlands on Venus raised by craton-like formation mechanisms,” the lead author, Fabio Capitanio, an Associate Professor from Monash University School of Earth, Atmosphere and Environment, spearheaded this research.

Ishtar Terra stands out as one of the three major highland regions on Venus. It features diverse topography including mountains, plains, and plateaus. The mountain chain known as Maxwell Montes in Ishtar Terra towers at approximately 11 km (6.8 mi) high, surpassing the height of Mt. Everest at 8.8 kilometers (5.5 mi).

Ishtar Terra displays intricate terrain that appears extensively deformed, indicating significant geological activity on Venus in its past.

Ishtar Terra also hosts Lakshmi Planum, a sprawling plateau covering two million square kilometers and rising about four km high, bordered by heavily deformed terrain. Comprised of smooth lava flows, the plateau features two massive shield volcanoes—Colette Patera measuring approximately 130 km in diameter, and Sacajawea Patera spanning about 200 km in width and 1-2 km in depth. Although Venus is presently devoid of tectonic activity, scientists theorize that ancient tectonic forces shaped the region’s dramatic topography.

The new findings in Nature Geoscience delve into a specific aspect of geology known as cratons, which are the ancient geological cores of Earth’s continents. These stable components of Earth’s lithosphere are typically situated at the heart of the planet’s continental plates, composed of durable basement rock with deep roots extending hundreds of kilometers into the mantle.

Some cratons trace back to the Precambrian era over 2.5 billion years ago, indicating their longevity and stability through Earth’s tumultuous geological history. Leveraging data from NASA’s Magellan spacecraft and advanced computer simulations, Capitanio and his team explored the formation of Ishtar Terra on Venus, uncovering parallels to Earth’s cratons.

“The structures emerging in this model provide topography, gravity, and crustal thicknesses remarkably comparable to the plateaus of Venus.” – Excerpt from “Ishtar Terra highlands on Venus raised by craton-like formation mechanisms.”

Capitanio et al.

While Earth’s plateaus and mountain belts result from continental collisions caused by plate tectonics, Venus, devoid of such tectonic activity, presents a different scenario. However, Ishtar Terra shares a common trait with Earth’s cratons—a thick crustal floor. This similarity implies shared processes between the planets, suggesting that Ishtar Terra and Venus’ other terrae may have emerged from the intense heat within the planet.

Despite the absence of plate tectonics on Venus, the planet’s scorching surface temperature of 460°C (860°F) extends into a lithosphere hotter and thinner than Earth’s due to Venus’s extreme greenhouse effect. This thin and weak lithosphere on Venus hints at “the emplacement of a thick magmatic crust on top of a deep residual depleted mantle” according to the research.

Lead author Capitanio remarked, “This research challenges our understanding of planetary evolution. Despite Venus’s extreme conditions and lack of plate tectonics, its complex geological features are unexpected.” By unveiling the similarities between Ishtar Terra and Earth’s early continents, the study opens new possibilities into the common evolutionary processes of both planets.

As researchers aim to decipher the mysteries of Earth’s history, studying Venus as a potential analogue could hold the key to unlocking Earth’s past. The similarities and differences between Earth and Venus offer valuable insights into planetary evolution and the diverse paths that rocky planets can follow.

While Venus may serve as an alternate model of early Earth, it remains a scorching world that contrasts the vibrant life on Earth. The ongoing exploration of Venus through upcoming missions like DAVINCI, VERITAS, and EnVision promises to provide deeper insights into the geological history of this intriguing planet.

Earth and Venus may have diverged in their courses, but they share deep connections at the geological level, offering a fascinating glimpse into the intertwined evolution of rocky planets in our Solar System.