Scientists have discovered that planets lacking Earth's key features could still support life.

It is believed that the existence of plate tectonics has played a crucial role in the emergence of life on Earth. This implies that if a terrestrial-type planet lacks plate tectonics, it cannot be habitable. However, the authors of a new study published in the journal Advancing Earth and Space Sciences have a different perspective, as reported by Universe Today.

Plate tectonics is considered an important factor in the formation of Earth and the evolution of life on our planet. Mars and Venus lack such processes, despite being terrestrial-type planets. These types of planets are relatively common in the universe, and many of them are also believed to lack plate tectonics, which suggests they are not suitable for life. Many terrestrial-type planets experience significant internal heating, which inhibits the movement of tectonic plates.

However, the new study indicates that on such planets, referred to by scientists as "Ignan Earths" (from the word ignition), there is a higher likelihood of thermal conduits that channel magma from the depths to the surface. As a result, the surface temperature of these planets resembles that of Earth during its hottest periods in history, when liquid water began to form.

Plate tectonics explains the movement and interaction of the Earth's upper layers, specifically the lithosphere, which consists of the crust and the upper mantle. It is divided into several sections known as tectonic plates that float on a semi-fluid layer below called the asthenosphere. Where tectonic plates meet, mountains, volcanoes, and basins are formed.

Plate tectonics is believed to have played a decisive role in the evolution of life on Earth. The movement of vast landmasses created new habitats and led to the isolation of populations, allowing distinct ecosystems to develop. Collisions between tectonic plates resulted in the formation of mountain ranges, which influenced weather patterns and climate. Volcanic activity caused by plate movement enriched soils and released gases, such as carbon dioxide, into the atmosphere, helping to create a more life-friendly climate on Earth.

Scientists believe that plate tectonics also prevents overheating of the planet's interior. Without such plate movements, the interior of Earth could become too hot for a stable environment to develop on the surface.

Researchers examined the likelihood that terrestrial-type planets with significant internal heating could be habitable. The study reveals that worlds with high internal temperatures should possess a solid mantle. The crust would remain largely stable due to the only likely activity, the tectonics of thermal conduits, where some internal heat is transferred to the surface, such as from volcanic activity.

Scientists modeled the probable range of surface temperatures on such planets based on various types of worlds and found that, contrary to previous assumptions, internal heating could indeed create a life-sustaining environment on these planets. In other words, these are terrestrial-type planets without plate tectonics that may still be habitable.