星空有约｜“套娃”四星系统破解褐矮星年龄之谜

Core Findings - An international team led by Nanjing University discovered a "nested" four-star system consisting of a pair of red dwarfs and a pair of brown dwarfs, located 82 light-years away, providing a rare sample for solving the age measurement problem of brown dwarfs [1][2] - The two pairs of binary stars in the system are separated by 1656 astronomical units, with an orbital period exceeding 100,000 years [1] - The red dwarfs have a surface temperature of approximately 2900 degrees Celsius and each has a mass of less than one-fifth that of the Sun, while the brown dwarfs have surface temperatures of only 550 degrees Celsius and 420 degrees Celsius [1] Age Measurement Insights - The age of the four-star system is estimated to be between 300 million and 2 billion years, derived from the intensity of hydrogen emission lines in the spectra of the red dwarfs, indirectly solving the age mystery of the two brown dwarfs [2] - The discovery of this four-star system is expected to serve as a benchmark reference for calibrating brown dwarf evolution models, which is significant for the study of "substellar" objects [2]