An international team led by Professor Zhu Wei from the Department of Astronomy at Tsinghua University recently announced the discovery of two rare star systems in the universe. This system is composed of two central stars orbiting each other, surrounded by a disk of gas and dust, and the disk is at a certain angle to the orbit of the central star, showing the fantastic effect of a "fog-orbiting double star."
A paper on the discovery of two new celestial bodies named Bernhard-1 and Bernhard-2 was recently published online in the international academic journal "The Astrophysical Journal Letters". The binary system rendering produced by the
scientific research team. (Photo courtesy of the scientific research team)
Protoplanetary disks are dense gas surrounding newly formed stars. It is understood that because the binary star and its protoplanetary disk are condensed from the same huge rotating nebula, the disk is usually in the same plane as the orbit of the star, just like the orbit of most planets in the solar system and the orbit of satellite is in Same on the same plane. But there is still a rare type of binary star system in the universe, that is, the protoplanetary disk surrounding the binary star is at a certain angle with the orbital plane of the star.
Zhu Wei introduced that due to this tilt, the protoplanetary disk will swing like a top, and this movement is called "precession." When "precession" occurs, the protoplanetary disk moves between the Earth and the star, orbiting the binary star every few decades, causing regular changes in the overall brightness of the binary star. In addition, due to the occlusion effect of the protoplanetary disk, the total brightness of the binary stars will also change periodically, producing a unique light curve. Two newly discovered objects, Bernhard-1 and Bernhard-2, are rare binary star systems of this type. The
scientific research team observed that Bernhard-1 dimmed 112 days out of every 192 days, while Bernhard-2 dimmed 20 days out of every 62 days. As seen from Earth, these dimmings indicate that one star in each binary is moving behind the disk. When the star reappears, the system's brightness returns to normal.
Zhu Wei said that these two binary star systems are 3,000 to 10,000 light-years away from the earth. Enthusiasts with telescopes with an aperture of 20 cm or more can see the process of their brightness changes, but unfortunately, existing telescopes It is not yet possible to distinguish between binary stars and protoplanetary disks.
"The discovery of this rare and peculiar system is of great significance to our understanding of planet formation." Zhu Wei said that since the protoplanetary disk is the birthplace of planets, the emergence of this binary star system will help researchers study incoplanarity more deeply. "We also believe that more such rare celestial bodies will be discovered in the near future."
Planner: Liu Xinhui
Wei Mengjia, Yang Menghan
Editor: Lianchang Yan
Xinhua News Agency Internal, Xinhua News Agency Beijing Branch co-produced
Starry Sky Studio produced
