THE WEEK - Small but mighty, the red planet — our celestial neighbor — has made Earth’s climate what it is today. Mars’ gravitational pull serves as a stabilizing force for our home’s orbit, tilt and position from the sun. Without it, life could potentially have been a lot different from what we know today.
How does Mars’ gravity impact Earth?
Despite being approximately half the size of Earth and one-tenth its mass, Mars’ gravity has had a sizable effect on Earth’s climate, according to a study published in the journal Publications of the Astronomical Society of the Pacific. Specifically, the red planet is “quietly tugging on Earth’s orbit and shaping the cycles that drive long-term climate patterns here,” said a release about the study.
Earth’s climate is largely driven by Milankovitch cycles, which are “long-term variations in our planet’s orbit and tilt governed by the gravitational pull of other planets in the solar system,” said Space.com (a sister site of The Week). One cycle takes approximately 430,000 years and is largely affected by Venus and Jupiter. Mars has little to no effect on this cycle, originally leading scientists to believe that the planet did not have much pull on Earth’s climate. However, it turns out that Mars “punches above its weight,” said Stephen Kane, the study leader and a professor of planetary astrophysics at the University of California, Riverside, in the release. Subtracting Mars from the equation significantly affected two other climate cycles, one of them 10,000 years long and the other 2.3 million years long. “When you remove Mars, those cycles vanish,” Kane said. “And if you increase the mass of Mars, they get shorter and shorter because Mars is having a bigger effect.”