Astrophysicists from Northwestern University and the University of California San Diego (UC San Diego) have made an extraordinary discovery – the tightest ultracool dwarf binary system ever observed. The two stars in the system, named LP 413-53AB, revolve around each other in an astonishingly short period of just 20.5 hours, making each star’s “year” shorter than a single day on Earth.
Ultracool dwarfs are a class of low-mass stars that emit light primarily in the infrared, making them invisible to the human eye. Despite this, they are one of the most common types of stars in the universe. The newly discovered system is composed of a pair of these ultracool dwarfs, which are estimated to be billions of years old – similar in age to our sun.
This discovery is particularly noteworthy as it represents a significant step forward in our understanding of ultracool dwarf binary systems. Previously, astronomers had only detected three short-period ultracool dwarf binary systems, all of which were relatively young, up to 40 million years old. LP 413-53AB has an orbital period that is at least three times shorter than any ultracool dwarf binary discovered so far.
“It’s exciting to discover such an extreme system,” said Chih-Chun “Dino” Hsu, a Northwestern astrophysicist who led the study. “In principle, we knew these systems should exist, but no such systems had been identified yet.”
Hsu is a postdoctoral researcher in physics and astronomy at Northwestern’s Weinberg College of Arts and Sciences and a member of Northwestern’s Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).
This groundbreaking discovery is a testament to the advancements made in the field of astrophysics and the dedication of the scientists at Northwestern University and UC San Diego. The data gathered from this system will provide invaluable insights into the nature of these mysterious stars and the workings of binary systems in the universe.