A team of researchers has discovered a stable trio of icy space rocks in the Kuiper Belt, a region of the solar system beyond Neptune. The finding, using data from NASA’s Hubble Space Telescope and the W.M. Keck Observatory in Hawaii, suggests there could be similar triples waiting to be discovered, which would support a particular theory of our solar system’s history and the formation of Kuiper Belt objects (KBOs).
The 148780 Altjira system is located about 3.7 billion miles away from Earth, or 44 times the distance between Earth and the Sun. Hubble images show two KBOs separated by approximately 4,700 miles (7,600 kilometers) but scientists say the inner object is actually a contact binary – two small bodies that have moved closer together to touch.
Researchers gathered data over 17 years, watching the orbit of the Altjira system’s outer object and noticed its orientation change. They then used modeling scenarios to determine that the best fit was a triple system. The finding provides crucial support for a KBO formation theory, which suggests three small rocky bodies form directly from gravitational collapse in the disk surrounding the newly formed Sun.
The study is published in The Planetary Science Journal. This discovery will provide scientists with an opportunity to learn more about the intriguing system over the next ten years, as it enters an eclipsing season where the outer body passes in front of the central body. NASA’s James Webb Space Telescope will also join the study to verify if the components look the same.
Source: https://science.nasa.gov/missions/hubble/nasas-hubble-finds-kuiper-belt-duo-may-be-trio