NASA's Hubble Finds Kuiper Belt Duo May Be Trio

Summary
A potential triple system of Kuiper Belt objects, only the second ever found, would support the theory that these rocky bodies form by gravitational collapse, like stars.
The universe contains a range of gravitationally bound three-body systems, from triple star systems to planets with two moons, like Mars. New research suggests that objects in the solar system's Kuiper Belt may also be in the triple club, as a second system, already identified as a binary, shows signs of containing a third member that is so close to its companion it can only be identified by observing the system's orbital dynamics. Confirming two triple systems in the Kuiper Belt would raise the likelihood that there are many other hidden triples there waiting to be recognized. The larger implication of this research is its support for a formation theory for Kuiper Belt objects known as the streaming instability hypothesis, which proposes that they formed not by collisions, but originated as triple systems through gravitational collapse.
Visit NASA Science to view the full news release including article text and associated Hubble imagery, graphics, scientific visualizations, videos, captions, text descriptions, and other information.
News releases highlighting the discoveries of NASA’s Hubble Space Telescope are produced for NASA by the Space Telescope Science Institute (STScI) in Baltimore, Maryland, under NASA Contract NAS5-26555. News release content is developed by the News Team in STScI’s Office of Public Outreach.
Pre-footer
Inbox Astronomy
Sign up to receive the latest news, images, and discoveries about the universe:
Contact our News Team
Ask the News Team
Contact our Outreach Office
Ask the Outreach Office