Dana Perry/NASA
Illustration showing how the gravity of giant planets can endanger rocky exoplanets in the habitable zone
Gas giant planets can be agents of chaos, ensuring that nothing survives on their Earth-like neighbors around other stars.
New studies show that in some planetary systems, giant planets tend to knock smaller planets out of their orbits and wreak havoc on their climates.
Jupiter, the largest planet in our solar system, plays an important role Protective sheet.
Its massive gravitational field deflects comets and asteroids that might collide with Earth, helping to create a stable environment for life.
However, giant planets elsewhere in the universe do not necessarily protect life on their smaller, rockier neighbors.
New article published In the magazine Astronomical magazine It details how the pull of massive planets in a nearby star system can push their Earth-like neighbors out of the “habitable zone.”
This area is defined as Distance rangeto the star that Warm enough There would be liquid water on the surface of the planet, making life possible.
Unlike most other known solar systems, the four giant planets HD 141399 They are farther from their star. This fact makes it A good model to compare with our solar systemWhere Jupiter and Saturn are also relatively far from the Sun.
“It is as if there are four Jupiters “They act like wrecking balls, throwing everything out of control.” Stephen KaneAstrophysicist at the University of California, Riverside, and author of the article published in the journal.
Taking into account data on the planets in the system, Ken ran several computer simulations to understand the influence of these four giants. The researcher specifically wanted to look into the habitable zone of this star system and see if it was possible for the Earth to remain in a stable orbit.
“The answer is yes, but it is very unlikely. “There are only a few specific regions where the gravity of the giants would not cause a rocky planet to break out of its orbit and fly out of the region,” Kane said.
While this scientific paper shows that giant planets outside the habitable zone eliminate the chances of life, Another articleThis shows how a large planet in the middle of the region could have a similar effect.
Also published in the magazine Astronomical magazineThis second work examines a star system just 30 light-years from Earth, called… GG357.
For reference, our galaxy is estimated to be 100,000 light-years across, so this system is “definitely in our neighborhood,” Kane said.
Previous studies have found that the planet in this system is called Gigajoule 357 d, lies in the system’s habitable zone and has been measured to be about six times the mass of Earth. However, in this second work, Kane demonstrates that mass exists Maybe much bigger than that.
“GJ 357d probably has a mass of up to 10 times that of Earth, which means it’s probably not Earth-bound, so There can be no life in it“Or at least it won’t be able to support life as we know it,” Ken said.
In the second part of the article, Kane and her collaborator, a postdoctoral fellow in planetary science at the University of California, Tara FeatherwolfThe researchers demonstrated that if the planet was much larger than thought, it would certainly prevent more Earth-like planets from settling in the habitable zone next to it.
While there are also some specific locations in the habitable zone of this system where Earth would likely exist, their orbits would be highly elliptical around the star.
“In other words, the orbits will produce crazy weather on these planets,” Kane said. “This paper is really a warning, when we find planets in the habitable zone, not to assume that they are automatically capable of supporting life.”
Ultimately, these two papers show how unusual it is to find the right set of conditions to support life elsewhere in the universe. “Our work gives us even more reason to be very grateful for the special planetary configuration we have in our solar system,” Keane said.
