Artist's depiction of an extra-solar system that is crowded with giant planets. Credit: NASA/Dana Berry
Topics: Astronomy, Astrophysics, Planetary Science, Space Exploration
Giant gas planets can be agents of chaos, ensuring nothing lives on their Earth-like neighbors around other stars. New studies show in some planetary systems, the giants tend to kick smaller planets out of orbit and wreak havoc on their climates.
Jupiter, by far the biggest planet in our solar system, plays an important protective role. Its enormous gravitational field deflects comets and asteroids that might otherwise hit Earth, helping create a stable environment for life. However, giant planets elsewhere in the universe do not necessarily protect life on their smaller, rocky planet neighbors.
An Astronomical Journal paper details how the pull of massive planets in a nearby star system is likely to toss their Earth-like neighbors out of the "habitable zone." This zone is defined as the range of distances from a star that are warm enough for liquid water to exist on a planet's surface, making life possible.
Unlike most other known solar systems, the four giant planets in HD 141399 are farther from their star. This makes it a good model for comparison with our solar system, where Jupiter and Saturn are also relatively far from the sun.
"It's as if they have four Jupiters acting like wrecking balls, throwing everything out of whack," said Stephen Kane, UC Riverside astrophysicist and author of the journal paper.
Taking data about the system's planets into account, Kane ran multiple computer simulations to understand the effect of these four giants. He wanted specifically to look at the habitable zone in this star system and see if an Earth could remain in a stable orbit there.
Giant planets cast a deadly pall: How they can prevent life in other solar systems, Jules Bernstein, University of California - Riverside, Phys.org.