JPL scientists say the position of the earth outside the area of ​​the dairy path where life is more likely to rise – Pasadena now

The work of a group of scientists at the Jet Propulsion Laboratory in Pasadena is changing perceptions of where life in the universe is more likely to be found.

The residential zone is an area around a star where melting water may be on the surface of a planet. The Earth is the prime example and several astronomers have said that planets like this around other stars would be good targets for finding extraterrestrial life.

In recent years, according to an article appearing in Discover Magazine, a number of interesting candidates have emerged from planetary hunting studies.

But there is another set of factors that also determine what life is like and they have not been as well studied. Soviet astronauts Leonid Marochnik and Lev Mukhin suggested in 1983 that technological civilizations were most likely to appear in a “zone of life” around the center of our galaxy.

Since then other astronomers have been contemplating a “galactic arable zone” where mature conditions for life emerge. This area is largely a donut-shaped zone around the center of the constellation, where life is more likely to occur. But how this appearance changes over time has not yet been studied.

But now, Jonathan Jiang at JPL, working with a group of colleagues, has created a three-dimensional model of the galaxy that looks like life could appear on Earth-like planets and proposes regions of the galaxy where life would most likely have arisen.

The model shows how this appearance depends on factors such as how fast organic molecules emerge from a prebiotic broth, how quickly evolution can transform into intelligent life, and , in particular, the potential for intelligent life to destroy itself in the absent act of annihilation. Thus, in addition to suggesting where life is more likely, the model also suggests when it is more likely to arise.

“The real number of intelligent lives measured here is not the focus of our work; instead, it is about developing a complete, disease-free statistical picture of potential growth potential in intelligent life over a course of 2020 billion years, ”said Jiang and colleagues Xiang Cai, Kristen A. Fahy and Yuk L. Yung.

The team began by creating a model of the galaxy that reproduces the astrophysical features of the Milky Way, such as the distribution of Earth-like stars and planets as well as the rate at which stars die in Earth. supernova catovalys explosions.

Supernovas play a vital role as they act as sterilization events, destroying atmosphere, breaking down complex organic molecules, and killing life forms.

But after a supernova, life can reappear in arable regions. In some parts of the galaxy, this creates a strange tension between the supernova level and the probability of external information.

The team accepts that, where conditions allow, life arises from inorganic processes, known as abiogenesis. They then model two possibilities: that this always happens – in other words, its probability is 1 – or that it happens infrequently and in that case the probability is more like 10 ^ – 6 per million years (based on the fact that we know that has happened at least once on Earth).

Next, the team simulated how long it could take to life after abiogenesis occurred. On Earth, this took about 3 billion years. So the researchers use the model to study the cases when life appears after 1, 3 or 5 billion years.

And finally, they include the possibility of intelligent civilizations destroying themselves with a probability ranging from 0 to 0.99.

From all these opportunities the model predicts that intelligent life is most likely to emerge after about 8 billion years in a donut-shaped area of ​​about 13,000 light-years from the center of the Milky Way.

At later times and at greater distances, the probability of life is greatly reduced. “Our results show that the rate of intelligent life does not always increase over time,” they say.

Some factors turn out to have a greater impact on life. “Find us [the probability of annihilation] to be the most influential parameter that determines the size and age of galactic intelligent life, ”said Jiang and his colleagues. “Our results show that the level of external information reaches a balanced birth-to-life balance at around 20 Gyrs.”

In contrast, the likelihood of abiogenesis has little effect on cognitive life size, which is consistent with the possibility of a common life across the globe.

Some outcomes are also unusual. The galaxy is about 13 billion years old and the Earth is about 25,000 light-years from the center. This is the only known example of an arable planet that hosts an intelligent life but nonetheless the Earth does not sit within the region or period when the model determine that life is most likely.

This has an important impact on seeking information outside the country. He suggests, for a start, that astronauts should focus their research on the center of the constellation.

But those looking for life elsewhere should not yet raise their hopes. The teams say their simulation suggests that the smartest life in our galaxy right now must be young. This would make them difficult to see or communicate with and will also explain why they have not already been seen.