Ultimately, we can understand our universe for one very simple reason: the science here and now is the same as the science everywhere and everywhen else. This means that just like we need a story that explains all the different-looking galaxies using the same physics, we also need a story that explains all the different solar systems with the same physics, such as explaining both the cold Jupiters like we have and the hot ones we’ve found orbiting so many stars on orbits smaller than Mercury’s.

And, according to a new paper accepted into The Astrophysical Journal Letters, a solution may come in the form of lucky and unlucky collisions.

In recent years, we’ve come to understand that our solar system was a very violent place, with a Mars-sized world hitting the early Earth and causing the formation of the Moon and other collisions fluffing out the core of Jupiter and flipping Venus on its head. It was very much a planet-hit-planet solar system, and there is even some evidence that interactions with other stars may have had their own influence on our solar system’s development. It was also a planet-yeet-planet solar system, with the gravitational tugs of Saturn and Jupiter hurling Uranus and Neptune into their distant locations.

In the grand scheme of things, our worlds have been lucky. We live in a magnificent system with a diversity of science, and no worlds are currently being destroyed by the Sun or flung to new places by our biggest planets.

But what if it went another way? In this new paper, coming from Malena Rice, Songhu Wang, and Gregory Laughlin, models show that interactions with a massive world or not too distant stars can evolve a world’s orbit, placing them on highly tilted or elongated paths that eventually migrate toward their sun, taking a healthy planet and putting it in a dangerously hot kind of place.

In the end, what we see is just a reflection of what collisions and interactions may have happened in the past, and it is the unlucky planet that ends up becoming a hot Jupiter.

One story, many worlds, all fit together. This is how science should be.

More Information

How ‘hot Jupiters’ may get their weirdly tight orbits (Science News)

“Origins of Hot Jupiters from the Stellar Obliquity Distribution,” Malena Rice, Songhu Wang, and Gregory Laughlin, 2022 February 18, The Astrophysical Journal Letters