Some planets may be better for life than Earth

Earth is not necessarily the best planet in the universe. Researchers have identified more than twenty planets outside our solar system that may have conditions more favorable to life than ours. Some of these orbiting stars may be even better than our sun.

A study by Washington State University scientist Dirk Schultz McCuch recently published in the journal Astrobiology Details of potential ‘super’ properties Planets, Which includes older, slightly larger, slightly warmer, and possibly wetter than Earth. Life could also thrive more easily on planets orbiting slowly changing stars with longer lifetimes than our sun.

The top 24 contenders for the super planets are over 100 Light years Away, but Schultz-McCuch said the study could help focus future monitoring efforts, such as NASA’s James Webb Space Telescope, the LUVIOR Space Observatory and the European Space Agency’s PLATO Space Telescope.

“With the upcoming space telescopes, we will have more information, so it is important to define some targets,” said Schultz-McCuch, a professor at WSU and the Technical University of Berlin. “We have to focus on the specific planets that have the most promising conditions for them Complicated life. However, we must be careful not to get stuck looking for a second Earth because there may be planets that may be more suitable for life than ours. “

For the study, geologist Scholes-McCuch collaborated with astronomers Renee Heller of the Max Planck Institute for Solar System Research and Edward Jinan of Villanova University to define habitability and research criteria among 4,500 known exoplanets. System of good candidates. Habitability does not mean that these planets definitely have life, it just means conditions that would aid life.

The researchers selected stellar planetary systems with potential terrestrial planets orbiting within them Host starLiquid water Residential area From the Kepler exoplanet archive of exoplanets transplants.

While the sun is our center Solar System, It has a relatively short lifespan of less than 10 billion years. Since it took nearly 4 billion years before any complex life form appeared on Earth, many of our sun-like stars, called G stars, could run out of fuel before complex life could develop.

In addition to looking at systems with cooler G-stars, the researchers also looked at systems with dwarf K stars, which are somewhat cooler, less intense, and less luminous than our sun. K stars It has the advantage of long life from 20 billion to 70 billion years. This will allow orbiting planets to be older as well as give life more time to progress to the complexity currently on Earth. However, for the planets to be habitable, they must not be so old that they have exhausted Earth’s heat and lack protective geomagnetic fields. Earth is about 4.5 billion years old, but researchers argue that the beautiful place of life is a planet between 5 billion and 8 billion years old.

Size and mass are also important. A planet that is 10% larger than Earth should have habitable space. A mass of more than 1.5 times the Earth’s mass would be expected to maintain its internal heating through radioactive decay for a longer period and would also have a stronger gravity to hold the atmosphere for a longer period of time.

Water is the key to life and the authors argue that a little bit of it may help, especially in the form of moisture, mists, and dampness. A slightly warmer temperature, and an average surface temperature of about 5 degrees Celsius (or about 8 degrees Fahrenheit) greater than Earth’s, plus the extra moisture, would also be better for life. This preference for warmth and moisture over land appears with greater biodiversity in tropical rainforests compared to cooler and drier regions.

Among the top 24 planet candidates, none of them meet all the criteria for a super habitable planet, but one has four important characteristics, which make it more comfortable for life than our home planet.

“Sometimes it’s difficult to convey this superoplanetary principle because we think we have the best planet,” said Schultz McCuch. “We have a large number of complex and varied life forms, many of which can survive in extreme environments. It is good to have an adaptive life, but that does not mean that we have the best of everything.”