Newfound Cosmic “Gateway” funnels small, icy objects to the inner Solar System

Beginning as small, icy bodies on the outskirts of the solar system, comets turn into spectacular streaks of light when they pass through a “gateway” near Jupiter, according to new research.

This gateway is a region of space where objects called centaurs — small, icy bodies that orbit between Jupiter and Neptune — start to nudge closer to the sun. As they do so, they heat up and become “active,” primarily releasing a dusty halo of gas — which makes these small bodies, technically, comets. “We realized there’s a nexus point in orbital space where small bodies change their orbit that we nicknamed ‘the gateway,’” said lead author Gal Sarid, a planetary scientist at the University of Central Florida.

The gateway region is like a donut that wraps around the inner solar system, containing many possible orbits within its thick ring. Sarid and his team first came up with the gateway idea after looking at a peculiar centaur named 29P/Schwassmann-Wachmann 1 or SWI. Though technically a centaur, SWI is very active, regularly releasing gases like a comet does, Sarid said.