Scientists have long been convinced that extraterrestrial life will be found on a planet resembling Earth. However, our planet was not always painted blue. New research indicates that you should rather focus on the orange planet, resembling the ancient Earth.
The idea is based on a simulation of the study of the potential of various exoplanets in the issue of life support. About 2.5 billion years ago, a hazy atmosphere sheltered our planet, allowing it to cool, so that ancient bacteria could develop. Researchers believe that when searching for extraterrestrial life, it is necessary to focus on similar chemical indicators.
In the Archean era, the Earth was shrouded in a dense organic, pale orange atmosphere created by ultraviolet light, splitting methane molecules into a “hydrocarbon haze”. At that time, the planet was observed little free oxygen, and the accumulation of methane was caused by living organisms.
In addition, in the Archean period the Earth was a hot and chaotic place. There was no ozone layer (from oxygen), so the planet received direct ultraviolet light threatening sterilization. To survive, life had to take shelter with the help of other types of UV shields.
Satellite Titan on the background of the majestic Saturn
With the help of photometric, climatic and radiation modeling of the early Earth, scientists have discovered that hydrocarbon haze will act as a buffer of ultraviolet light, which will allow the planet to cool and evolve living organisms.
This suggests that haze will play a role not only a sign of biological life, but also a shield that allows these organisms to develop into more complex bacteria, primitive plants and animals.
Researchers have not yet managed to identify signs of an early earthly atmosphere, such as fog and haze. But there are several worlds in which clouds and light haze of unknown composition are observed. In fact, one of these facilities is located nearby. This is Saturn’s satellite Titan, which has a haze that resembles the earth in the Archean period (let's not forget about the lakes).
Of course, life is able to survive even in extreme conditions. But it is better now to focus on the conditions necessary for the existence of the most elementary organisms. Therefore, scientists propose to study in detail the situation of the ancient Earth and look for something similar in other worlds.