All posts tagged: Binary Stars

Massive binary star system may be feeding the Milky Way’s central black hole

Massive binary star system may be feeding the Milky Way’s central black hole

Published by Jenni Sidey

A string of small gas clouds near the Milky Way’s central black hole has puzzled astronomers for years. Now, new observations suggest those clouds are not random scraps drifting through space. They appear to be part of a larger flow of material, and a massive binary star may be creating them. At the center of the galaxy sits Sagittarius A*, or Sgr A*, a supermassive black hole surrounded by stars, gas, and dust moving through an extreme gravitational environment. Astronomers have long treated this region as a natural test site for watching how matter behaves near a black hole. One of the lingering mysteries has been a set of compact gas clumps found close to Sgr A* in infrared observations. The first of those objects, called G2, was identified in 2012. It looked like a dusty, ionized gas cloud with hydrogen and helium emission, a temperature of about 600 kelvin, and a mass estimated at no more than about 3 Earth masses. It was also stretched out by gravity as it moved along a highly …

Astronomers solve decades-old mystery of flickering binary stars

Astronomers solve decades-old mystery of flickering binary stars

Published by Jenni Sidey

Faint flickers in the night sky have puzzled astronomers for decades. These subtle changes in brightness come from violent star systems, where one star feeds on another. Now, new research from the University of Nevada, Las Vegas, offers a clearer explanation for one of the most confusing signals these systems produce. The study challenges a long-standing idea about how certain brightness patterns form. By rethinking the shape of matter swirling around dead stars, scientists may have solved a mystery that has lingered for nearly 50 years. A Strange Rhythm in the Night Sky Some stars do not shine steadily. Instead, they pulse, flicker, and flare. In certain cases, that rhythm comes from a pair of stars locked in a tight orbit. The eccentricity (upper panels) and periapse angle (lower panels) versus radius of the disk for three different values of H/r and q = 0.1. (CREDIT: The Astrophysical Journal Letters) These systems, called cataclysmic variables, involve a dense white dwarf pulling material from a nearby companion star. The stolen gas spirals inward, forming a glowing …

Astronomers discover the binary origin of fast radio bursts

Astronomers discover the binary origin of fast radio bursts

Published by Jenni Sidey

New insights are emerging into one of astronomy’s most perplexing signals. An international research team led in part by scientists from the University of Hong Kong has found strong evidence that at least some fast radio bursts come from stars locked in binary systems rather than single stars. The work centers on a repeating fast radio burst called FRB 20220529, also known as FRB 220529A. Using China’s Five-hundred-meter Aperture Spherical Telescope, known as FAST, and Australia’s Parkes radio telescope, researchers tracked the source for nearly two years. Their results were published in the journal Science. Professor Bing Zhang, an astrophysicist at the University of Hong Kong and founding director of the Hong Kong Institute for Astronomy and Astrophysics, served as a corresponding author on the study. He and his colleagues report what they describe as the first decisive evidence that a repeating fast radio burst source can orbit a companion star. “This finding provides a definitive clue to the origin of at least some repeating FRBs,” Zhang said. “The evidence strongly supports a binary system …