Emily Simpson, a passionate space enthusiast and recent Florida Tech graduate, has published groundbreaking research that imagines an alternate version of our solar system.
Instead of the asteroid belt between Mars and Jupiter, what if a massive planet—a “super-Earth”—had formed there instead?
Her study sheds light on how such a planet could have dramatically changed the habitability of Earth and its neighboring planets.
Simpson’s research, published in the journal Icarus, was co-authored by her advisor, Dr. Howard Chen, an assistant professor of planetary science.
Together, they created a 3D model to simulate how a super-Earth in place of the asteroid belt might have affected the inner planets of our solar system—Venus, Earth, and Mars.
Since the discovery of the first exoplanet in 1992, scientists have been fascinated by how other planetary systems compare to ours.
Dr. Chen explained that most other solar systems are more compact and often include super-Earths, planets at least twice the size of Earth. Our solar system is rare, lacking such a planet.
By studying the potential effects of a super-Earth in our solar system, Simpson and Chen aim to help astrobiologists identify other systems that could support life. If we discover a solar system with a super-Earth in a similar position, would its inner planets still be habitable?
Simpson’s model tested five possible masses for a super-Earth, ranging from 1% of Earth’s mass to 10 times Earth’s mass. She simulated 2 million years of orbital changes to see how the hypothetical planet would influence the tilt (obliquity) and orbit shape (eccentricity) of the inner planets.
- Obliquity affects the intensity of seasonal temperatures. Greater tilt leads to extreme seasons, while less tilt creates milder ones.
- Eccentricity determines the length of seasons. A circular orbit results in even seasons, while an elliptical orbit causes uneven seasonal lengths.
The results showed that smaller super-Earths (one or two times Earth’s mass) had minimal impact. Mars wobbled a bit more on its axis, but Earth and the other inner planets remained stable and habitable. According to Chen, “We might have slightly hotter summers or colder winters, but life could still go on.”
However, larger super-Earths had more dramatic effects. A planet 10 times Earth’s mass caused severe changes to the inner planets’ tilt and orbits. Seasons became dangerously extreme, with scorching summers and freezing winters. Earth’s orbit might even have shifted closer to Venus, pushing it out of the habitable zone.
While this study is hypothetical, it helps scientists understand how planets in other solar systems could affect their neighbors. It also provides insight into how large a super-Earth can be before making nearby planets uninhabitable.
“If we discover a solar system with a super-Earth instead of an asteroid belt, we’ll need to consider its size carefully,” Simpson said. “A massive super-Earth could spell doom for life on the inner planets.”
Simpson’s research offers a fascinating glimpse into the delicate balance that makes our solar system—and life on Earth—possible.
