CAMBRIDGE, Massachusetts — New radio images of Betelgeuse show the red supergiant has largely recovered from its dramatic fading of late 2019 and early 2020 — but they also reveal something stranger: the shape of the giant star's outer atmosphere stretches and relaxes in step with the orbit of a hidden companion, Siwarha, which circles so close that it passes through the star's extended atmosphere. The findings come from a study led by Dr. Lynn D. Matthews of the MIT Haystack Observatory, with colleagues from the Center for Astrophysics | Harvard & Smithsonian, the University of Manchester and the European Southern Observatory. Published in The Astronomical Journal, it is based on observations from 2021 to 2026 at seven radio frequencies, 22 to 485 gigahertz, using the Karl G. Jansky Very Large Array in New Mexico and the Atacama Large Millimeter/submillimeter Array, known as ALMA, in Chile. According to the National Radio Astronomy Observatory, which announced the resu...