Press Release

A research team, composed of climatologists and an astronomer, have used an improved computer model to reproduce the cycle of ice ages (glacial periods) 1.6 to 1.2 million years ago. The results show that the glacial cycle was driven primarily by astronomical forces in quite a different way than it works in the modern age. These results will help us to better understand the past, present, and future of ice sheets and the Earth’s climate. (May 15, 202３ press release)

Recently, hundreds of gold-rich stars have been detected by state-of-the-art telescopes worldwide. New simulations of galaxy formation, with the highest resolution in both time and mass, show that these gold-rich stars formed in progenitor galaxies, small galaxies which merged to create the Milky Way. (November 14, 2022 press release)

A research group led by Nanae Domoto, a graduate student at the Graduate School of Science at Tohoku University and a research fellow at the Japan Society for the Promotion of Science (JSPS), has systematically studied the spectra from this kilonova—bright emissions caused by the radioactive decay of freshly synthesized nuclei that were ejected during the GW170817 merger. Based on comparisons with detailed simulations of kilonova spectra produced by the supercomputer “ATERUI II” at the National Astronomical Observatory of Japan, the team found that the rare earth elements lanthanum and cerium can reproduce the near-infrared spectral features seen in 2017. (October 27, 2022 press release)

A new simulation conducted on the world’s most powerful supercomputer dedicated to astronomy has produced a testable scenario to explain the appearance of the bar of the Milky Way. Comparing this scenario to data from current and future space telescopes will help clarify the evolution of our home Galaxy. (September 9, 2022 press release)

A new technique combining artificial intelligence trained by supercomputer simulations and astronomy Big Data has enabled astronomers to analyze data with undreamed of speed to determine the unknown characteristics of the Universe.

A research group at the University of Tokyo has performed a simulation of star cluster formation using a newly developed simulation code. The simulation revealed that some massive stars formed in the star cluster center were ejected to the outskirts of the cluster and ionized the molecular cloud there. These processes caused the formation of off-centered ionized bubbles seen in the Orion Nebula.

The world’s first 3D simulation simultaneously considering dust motion and growth in a disk around a young star has shown that large dust from the central region can be entrained by and then ejected by gas outflows, and eventually fall back onto the outer regions of the disk where it may enable planetesimal formation. This process can be likened to volcanic “ashfall” where ash carried up by gas during an eruption falls back on the area around the volcano. These results help to explain observed dust structures around young protostars.

Forming planets are one possible explanation for the rings and gaps observed in disks of gas and dust around young stars. But this theory has trouble explaining why it is rare to find planets associated with rings. New supercomputer simulations show that after creating a ring, a planet can move away and leave the ring behind. Not only does this bolster the planet theory for ring formation, the simulations show that a migrating planet can produce a variety of patterns matching those actually observed in disks.

An international team of researchers developed the largest and most detailed simulation of the Universe to date and has made it freely available on the cloud to everyone. This simulation, named Uchuu, will help astronomers to interpret results from Big Data galaxy surveys.

Japanese astronomers have developed a new artificial intelligence (AI) technique to remove noise in astronomical data due to random variations in galaxy shapes. After extensive training and testing on large mock data created by supercomputer simulations, they then applied this new tool to actual data from Japan’s Subaru Telescope and found that the mass distribution derived from using this method is consistent with the currently accepted models of the Universe. This is a powerful new tool for analyzing big data from current and planned astronomy surveys.