With the help of the Gemini North Telescope and Subaru Telescope, a team of astronomers, including the University of Tokyo in Japan, have discovered two merging quasars that emerged only 900 million years after the Big Bang. This is not only the farthest discovered pair of merged quasars, but also the first confirmed pair of merged quasars during the Dawn of the Universe. The relevant paper was published in the latest issue of the Astrophysical Journal Letters. The time span of the Dawn of the universe is approximately 50 million years after the Big Bang to 1 billion years after the Big Bang. During this period, the first batch of stars and galaxies began to appear, and the dark universe was filled with light for the first time. The arrival of the first batch of stars and galaxies ushered in a new era of cosmic formation, known as the Reionization Age. The era of re ionization at the dawn of the universe is a transitional period in cosmology. Starting approximately 400 million years after the Big Bang, the first batch of ultraviolet radiation emitted by stars, galaxies, and quasars spread throughout the universe, interacting with intergalactic media and stripping the electrons of primitive hydrogen atoms in a process known as ionization. The era of re ionization is a crucial period in the history of the universe, marking the end of the dark era of the universe. Astronomers have been searching and analyzing distant quasars in order to understand their exact role in the era of re ionization. They have discovered approximately 300 quasars from the re ionization era, but have not yet observed a pair of quasars merging. The research team was attracted by a faint red color while examining the images captured by the Subaru telescope. To confirm the properties of these celestial bodies, they conducted subsequent spectral analysis using the weak object camera and spectrometer (FOCAS) on the Subaru telescope and the Gemini near-infrared spectrometer (GNIRS) on the Gemini North telescope. The results confirm that these objects are quasars. Researchers suggest that the era of re ionization links the earliest formation of cosmic structures to the complex universe observed by humans. Studying distant celestial bodies during this period can help people further understand the process of re ionization and how the first batch of celestial bodies in the universe were formed. (Lai Xin She)