北京大学科维理天文与天体物理研究所

Featured Science

Unknown Treasure Trove of Planets Found Hiding in Dust

"Super-Earths" and Neptune-sized planets could be forming around young stars in much greater numbers than scientists thought, new research by an international collaboration of astronomers suggests. Observing a sampling of young stars in a star-forming region in the constellation Taurus, the team found many of them to be surrounded by structures that can best be explained as traces created by invisible, young planets in the making. The results, published in the Astrophysical Journal, help scientists better understand how our own solar system came to be.

Astronomers Unveil Growing Black Holes in Colliding Galaxies

A team of researchers led by Michael Koss (Eureka Scientific Inc.), and including Claudio Ricci, long-term visiting professor at KIAA, performed the largest survey of the cores of nearby galaxies in near-infrared light, using high-resolution images taken by NASA's Hubble Space Telescope and the W. M. Keck Observatory in Hawaii. The Hubble observations represent over 20 years' worth of snapshots from its vast archive.

Weighing planets and asteroids: Pulsar observations enable mass estimates for Ceres and other solar system objects

A team of scientists from the `International Pulsar Timing Array’ consortium, led by researchers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has used pulsar timing data to measure the masses of the dwarf-planet Ceres and other asteroids. The result for the mass of Ceres is 1.3% of the mass of the Earth’s moon. The team has also measured the masses of the major planets of the solar system with much improved precision than a past study and demonstrated how pulsar-timing data can be used to explore unknown massive objects orbiting the Sun. The results are presented online as refereed publication in the “Monthly Notices of the Royal Astronomical Society”.

Discovery of the Largest Protocluster of Galaxies in the Distant Universe

An international team of astronomers led by Youth Qianren Research Professor Linhua Jiang at KIAA-PKU discovered a giant protocluster of galaxies at redshift 5.7, when the Universe was only one billion years old (about 7% of its current age). This protocluster will collapse into a galaxy cluster with a total mass of ~ 3.6 × 10^15 solar masses, making it the most massive protocluster currently known at high redshift.

New Discoveries Double the Number of Changing-look AGNs

A team led by Prof. Xue-Bing Wu, the Associate Director of KIAA, has conducted a survey of changing-look quasars in the last two years. They have discovered 21 changing-look quasars at redshift from 0.08 to 0.58, including 5 from repeat spectra in SDSS archive, 10 from repeat spectra in SDSS and LAMOST, and 6 from new spectroscopic observations of photometric variability selected candidates with the 2.16m Xinglong telescope at NAOC.

First observational indication of the gravitomagnetic monopole and naked singularity

The first significant observational indication of the gravitomagnetic monopole has recently been reported by Dr. Chandrachur Chakraborty from Kavli Institute for Astronomy and Astrophysics, Beijing, China and Prof. Sudip Bhattacharyya from Tata Institute of Fundamental Research, Mumbai, India, based on the X-ray observations of an astrophysical collapsed object : GRO J1655-40. They have inferred that this object not only contains the non-zero gravitomagnetic monopole but their result tentatively suggests that the above mentioned astrophysical collapsed object could also be a naked singularity.