And as scientists search for other planets outside our solar system, called extraterrestrial planets that can accommodate life, planets that are very similar to Earth may not be the best answer.
In a new study, Schulze-Makuch and his co-authors identified 24 extraterrestrial planets and extraterrestrial planetary candidates (planets that were not conclusively identified as extraterrestrial planets). They are all more than 100 light-years apart and can be a contender for a superhuman planet with conditions more suitable for life than Earth.
However, the authors warn that this does not mean that they have confirmed the existence of life on this planet. Instead, it means that these planets can have conditions that are conducive to life.
Schulze-Makuch said, “While we’re looking for a superhuman planet, we warn that it doesn’t necessarily mean that it contains life (or complex life).” “Planets may be habitable or super-fast habitable, but they may not be inhabited. This has to do with the planet’s natural history. There may have been a disaster such as a nearby supernova explosion.”
Schulze-Makuch identifies the superhuman planet as “a planet that currently has more biomass and biodiversity than Earth.” In essence, he said it would be slightly older, bigger, warmer and more humid than Earth.
“The habitability of our planet has also changed through our natural history,” he said. “For example, a Carboniferous Earth with all the swamps and rainforests (which now produced most of the gas and oil) was more habitable than the current Earth.
A star with a longer life
One factor in super habitability may actually be the type of star the planet orbits. Researchers identify the most ideal K dwarf stars in their studies. Because these stars have a longer lifespan than our Sun, life can potentially persist and thrive on the planets orbiting them.
K dwarf stars are colder, less heavier, and much less shiny than ours. But they can last 20 to 70 billion years. The planets orbiting these stars are older, allowing time for life to reach complexity on Earth.
Earth is about 4.5 billion years old. However, in the study, researchers suggest that 5 to 8 billion years is actually a “sweet spot” for life to form and evolve.
Our sun’s lifespan is less than 10 billion years, and it took nearly 4 billion years for complex life forms on Earth to evolve. And stars similar to our sun can actually die before complex life forms on orbiting planets.
Of the 4,500 known alien planets, different criteria were used to determine the super habitability.
Planets were Earth-like or Earth-like rocky, and appear to orbit in the habitable areas of the stars. In other words, it refers to the distance to the stars at which liquid water can remain stable on the surface of an alien planet.
They looked at their size and mass and estimated that a planet, about 1.5 times Earth’s mass, would have a stronger gravitational force that could sustain its internal heating longer than Earth and hold its atmosphere longer.
On Earth, which is about 8 degrees Fahrenheit warmer than Earth, a higher moisture content may be more suitable for life. The study authors compared this preference for warmth and moisture with the biodiversity of the global rainforest. Especially when compared to colder and drier regions.
The most important of these criteria, Schulze-Makuch believes, is that the planet is hosted by a K dwarf and the planet is slightly older than Earth.
The planet is superpopulated and can only meet some criteria without checking all the boxes, but the author warns that there is more information about this planet that cannot be evaluated.
Schulze-Makuch warned that “slightly higher temperatures could exacerbate the situation in times of inhabitable like extreme deserts on Earth.”
Finding a world where a person can live
It is located in the constellation of Swan, about 3,000 light-years from Earth. The star is only 77% of our solar radius, 76% of its mass, and 34% of our solar luminosity. And the star is about 5.5 billion years old, that is, 1 billion years older than our sun.
The authors give some transcripts of the stars orbiting in their studies based on what they know, and I admit that there aren’t many.
Schulze-Makuch said, “The point is that prospective candidates who are likely to be habitable or super habitable should be selected and prioritized for further investigation.” “And we need to better understand what makes the planet habitable and how the biosphere interacts with its natural environment.”
However, to fully evaluate these candidates, Schulze-Makuch believes that a rover or planetary landing is needed. However, it is unlikely that all of this will be too far away. However, better remote observations with future space telescopes could help you focus more on the details of these planets.
Schulze-Makuch said, “It is sometimes difficult to convey the principle of a superpopulated planet because we think we have the best planets.” “We have a lot of complex and diverse life forms and many creatures that can survive in extreme environments. It’s good to live an adaptable life, but that doesn’t mean we have the best of all.”
Sara Seager, an astronomer and planetary scientist, sees the work as “a great resource that everyone can use as a reference.” Seager, who is also a professor at the Massachusetts Institute of Technology, did not participate in the study.
In an email to CNN, Seager said, “It’s a really cool explanation of every aspect of the inhabitable world.” “I like the superhuman alien planet concept, which is as good as the Olympic athletes among us humans.”
And Seager agrees with what the author says at the conclusion of the paper.
“Observation of inhabitable or super-inhabitable alien planets is still very challenging, so nature will ultimately determine what targets can be tracked with next-generation telescopes,” Seager said.
“This is a follow-up to determine if the planet is actually habitable and if there is water vapor in the atmosphere (representing the surface water of a rocky planet), potentially measuring the planet and searching for biometric gases.
“So the list of samples of extraterrestrial planets is quite long, but none are within 100 light years, Not suitable for follow-up observations on our next-generation telescopes. “