 Beneath the apparent diversity and complexity in morphology, galaxies show underlying simplicity and have universally bimodal distributions of normalized specific angular momentum of stars, according to a study led by KIAA/PKU researchers Dr. Bitao Wang and Prof. Yingjie Peng. These two prevailing galaxy populations, dominated respectively by chaotic random motion and ordered bulk rotation, are shown to have experienced contrasting evolutionary histories. The work is published in the Sept 27 issue of Nature Astronomy.
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 Recently, a team of astrophysicists, including Dr. Haoxiang Lin and Prof. Zhuo Li from the Kavli Institute for Astronomy and Astrophysics (KIAA), Peking University and the GECAM (The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor) team led by Prof. Shaolin Xiong from Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, has two groundbreaking papers about GRB 221009A, recently published in The Astrophysical Journal Letters, shedding new light on the physics of GRB jets.
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 A research team led by Ke Wang at KIAA used the Five-hundred-meter Aperture Spherical radio Telescope (FAST) to observe two typical filamentary giant molecular clouds (GMCs) in the center of the Milky Way's spiral arms (also known as the "skeleton" structure), and discovered cold neutral hydrogen commonly associated with molecular CO emission. From the complex HI spectral-line cubes observed by FAST, the astronomers extracted HI narrow self-absorption (HINSA) signals to single out cold neutral hydrogen condensed from ambient warm and hot medium. HINSA marks cold atomic gas, and its association with molecular CO emission shows ongoing transition from atomic to molecular gas, i.e., the formation of GMCs.
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 In a powerful match-up of technique, instrumentation, and target, an international team of astronomers led by Jessica Speedie, under the supervision of her advisor Prof. Ruobing Dong, who recently joined KIAA, observed the well-characterized protoplanetary disk around AB Aurigae and found observational evidence that matches the alternative “top-down” theoretical sequence of planet formation.
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 Recently, the international scientific journal Nature Astronomy published online the paper "A slightly oblate dark matter halo revealed by a retrograde precessing Galactic disk warp", which is jointly led by the University of Chinese Academy of Sciences , Peking University, the National Astronomical Observatory of the Chinese Academy of Sciences, and Shanghai Jiao Tong University. The international team pioneered the "motion picture" method for measuring the precession rate of the Milky Way's disk warp. Using a sample of Cepheid variable stars of different ages, this method allows the precession direction and rate of the Milky Way's warp to be clearly observed. Based on these measurements, the research team revealed that the current dark matter halo of the Milky Way is slightly oblate.
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 KIAA announces an advancement in cosmic exploration with the release of the CatNorth quasar candidate catalog, as recently published in The Astrophysical Journal Supplement Series. The international collaborative study, led by Dr. Yuming Fu and Prof. Xue-Bing Wu, presents an enhanced set of over 1.5 million reliable quasar candidates, building upon the initial Gaia DR3 quasar candidate catalog noted for its substantial size but low purity.
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