2:45 PM - 3:00 PM
[MZZ45-05] Optical wide-field video observation system Tomo-e Gozen on the Kiso Schmidt telescope, the Universoity of Tokyo and its recent research of near-earth asteroids
Keywords:Optical wide-field video observation system, Tomo-e Gozen, near-earth asteroid
Tomo-e Gozen is an optical wide-field video observation system composed of a mosaic CMOS camera on the 1.05 m Kiso Schmidt telescope, operated by Institute of Astronomy, Graduate School of Science, The university of Tokyo, real-time data analysis software, and automated operation software. Consecutive images at 2 fps with a field-of-view of 20 deg2 are obtained with 84 chips of CMOS image sensors. Produced data of 30 TByte/night are processed by advanced data science methods in real time. A high-speed data acquisition capability of CMOS image sensor enables a quick scan of the sky as well as a high-speed monitoring with sub-sec time resolution.
Many mechanical innovations have been implemented to position the sensors with high precision across the wide focal plane, a characteristic of the Schmidt Telescope. Monochromatic all-sky video-survey of 12,000 square degree and high-cadence video-survey of 3,000 square degree are now ongoing. When receiving alerts of gravitational wave events, automated follow-up observations of a few 100 square degree start quickly. The high-speed observation capability with precise timestamps achieved by GPS allows us to carry out simultaneous monitoring of short time-scale variables with X-ray and radio telescopes. Such high-speed, high time cadence, and wide-field observations with Tomo-e Gozen are expected to make a significant contribution to the early detection of asteroids approaching the Earth, and to open up a new field of astronomical knowledge on short-time variable phenomena such as faint meteors, occultations of small solar-system objects, supernovae in the early stages of explosion, black hole binarys, optical counterparts of gravitational wave sources and FRBs, and unknown flashes in the Universe.
Recently many near-earth asteroids with orbits close to the Earth have been discovered by survey observation projects around the world. Our asteroid exploration research group is also searching for near-earth asteroids using nightly survey observation data from Tomo-e Gozen. By conducting follow-up observations of asteroid candidate objects detected from survey observation by Tomo-e Gozen, we have successfully discovered 49 small asteroids with diameters of less than 100 m from the start of observations in 2019 to end of 2022. These were given asteroid provisional designations by the International Astronomical Union (IAU) Minor Planet Center (MPC). Many of the asteroids discovered by us are extremely near-earth asteroids that pass within three times the Earth-Moon distance and have been overlooked by previous observations. We have also succeeded in detecting many high-speed rotations of small asteroids from instantaneous tracking observations using Tomo-e Gozen.
Many mechanical innovations have been implemented to position the sensors with high precision across the wide focal plane, a characteristic of the Schmidt Telescope. Monochromatic all-sky video-survey of 12,000 square degree and high-cadence video-survey of 3,000 square degree are now ongoing. When receiving alerts of gravitational wave events, automated follow-up observations of a few 100 square degree start quickly. The high-speed observation capability with precise timestamps achieved by GPS allows us to carry out simultaneous monitoring of short time-scale variables with X-ray and radio telescopes. Such high-speed, high time cadence, and wide-field observations with Tomo-e Gozen are expected to make a significant contribution to the early detection of asteroids approaching the Earth, and to open up a new field of astronomical knowledge on short-time variable phenomena such as faint meteors, occultations of small solar-system objects, supernovae in the early stages of explosion, black hole binarys, optical counterparts of gravitational wave sources and FRBs, and unknown flashes in the Universe.
Recently many near-earth asteroids with orbits close to the Earth have been discovered by survey observation projects around the world. Our asteroid exploration research group is also searching for near-earth asteroids using nightly survey observation data from Tomo-e Gozen. By conducting follow-up observations of asteroid candidate objects detected from survey observation by Tomo-e Gozen, we have successfully discovered 49 small asteroids with diameters of less than 100 m from the start of observations in 2019 to end of 2022. These were given asteroid provisional designations by the International Astronomical Union (IAU) Minor Planet Center (MPC). Many of the asteroids discovered by us are extremely near-earth asteroids that pass within three times the Earth-Moon distance and have been overlooked by previous observations. We have also succeeded in detecting many high-speed rotations of small asteroids from instantaneous tracking observations using Tomo-e Gozen.