Optical observations of NEA 3200 Phaethon (1983 TB) during the 2017 apparition

The near-Earth asteroid 3200 Phaethon (1983 TB) is an attractive object not only from a scientific viewpoint but also because of JAXA's DESTINY+ target. The rotational lightcurve and spin properties were investigated based on the data obtained in the ground-based observation campaign of Phaethon. We aim to refine the lightcurves and shape model of Phaethon using all available lightcurve datasets obtained via optical observation, as well as our time-series observation data from the 2017 apparition. Using eight 1-2-m telescopes and an optical imager, we acquired the optical lightcurves and derived the spin parameters of Phaethon. We applied the lightcurve inversion method and SAGE algorithm to deduce the convex and non-convex shape model and pole orientations. We analysed the optical lightcurve of Phaethon and derived a synodic and a sidereal rotational period of 3.6039 h, with an axis ratio of a/b = 1.07. The ecliptic longitude (lambda) and latitude (beta) of the pole orientation were determined as (308, -52) and (322, -40) via two independent methods. A non-convex model from the SAGE method, which exhibits a concavity feature, is also presented.Comment: 14 pages, 4 figures, 1 figure in Appendix A. Accepted for publication in Astronomy & Astrophysics (A&A

Korean Academy of Medical Sciences Pediatric Impairment Guideline for Brain Lesion

The permanent impairment evaluation for children in developmental stage is very difficult and it is even impossible in some cases. The impairment evaluation for developing children has not yet been included in the guideline of the American Medical Association. Due to frequent medical and social demands in Korea, we developed an impairment evaluation guideline for motor impairment, intellectual disability/mental retardation, developmental speech-language disorder and epilepsy caused by pediatric cerebral injuries, or cerebral lesions other than the developmental disorders such as autism. With the help of various literature and foreign institutions, we developed our in order to develop a scientific guideline for pediatric impairment that is suited to Korean cultural background and social condition

International Asteroid Warning Network Timing Campaign : 2019 XS

Peer reviewe

Apophis planetary defense campaign

We describe results of a planetary defense exercise conducted during the close approach to Earth by the near-Earth asteroid (99942) Apophis during 2020 December–2021 March. The planetary defense community has been conducting observational campaigns since 2017 to test the operational readiness of the global planetary defense capabilities. These community-led global exercises were carried out with the support of NASA's Planetary Defense Coordination Office and the International Asteroid Warning Network. The Apophis campaign is the third in our series of planetary defense exercises. The goal of this campaign was to recover, track, and characterize Apophis as a potential impactor to exercise the planetary defense system including observations, hypothetical risk assessment and risk prediction, and hazard communication. Based on the campaign results, we present lessons learned about our ability to observe and model a potential impactor. Data products derived from astrometric observations were available for inclusion in our risk assessment model almost immediately, allowing real-time updates to the impact probability calculation and possible impact locations. An early NEOWISE diameter measurement provided a significant improvement in the uncertainty on the range of hypothetical impact outcomes. The availability of different characterization methods such as photometry, spectroscopy, and radar provided robustness to our ability to assess the potential impact risk

CCD Photometry of the Globular Cluster M30

We present UBV CCD photometry of the metal-poor globular cluster M30. The data were obtained using the 40 inch telescope at Mt. Stromlo and Siding Spring Observatory (MSSSO). We used DAOPHOT CCD reduction package in order to obtain Color-Magnitude Diagram (CMD). We have derived some fundamental parameters of the globular cluster such and metal abundance ([Fe/H]), helium abundance (Y), and distance modulus (m-M) from the CMD. The derived parameters were [Fe/H]=-2.05, Y=0.28, and (m-M)=14.64. From the latter, the distance of 8.3kpc is obtained. Despite the photometric uncertainty near the main-sequence turnoff, we estimate the age of M30 to be 1.6¡¾3 Gyrs from the Revised Yale Isochrones. If[O/Fe]=+0.4, this age will be reduced to 14.2¡¾3 Gyrs

CCD Photometry of the Globular Cluster NGC 4372

We present a deep (B, V) color-magnitude diagram (CMD) of the Galactic globular cluster NGC 4372. According to the recent inside-out picture of Galaxy formation, this cluster is predicted to be one of the oldest globular clusters in the Galaxy. Our CMD shows a well defined main-sequence extending ~2 magnitudes below the turnoff. Despite the uncertainty that stems from, the small sample size of bright stars, comparison with the Revised Yale Isochrones suggests in our Galaxy

Development of an AutoFlat program for the acquisition of effective flat images in the automated observation system

The purpose of this study is to develop an observation program for obtaining effective flat images that are necessary for photometric observation. The development of the program was achieved by improving the existing method for obtaining twilight flat images. The existing method for obtaining twilight flat images acquires flat images by observing the sky light after sunset or light before sunrise. The decision of when to observe flat images at each night is solely dependent on the judgment of an observer, and thus the obtained flat images for particular nights may not be clean. Especially, in the case of the observatories where an automated observation system is in operation, there is a difficulty that an observer should pay attention during sunrise and sunset in order to obtain flat images. In this study, a computer program is developed to improve this inconvenience and to efficiently perform photometric observation in the observatories where an automated observation system is applied. This program can obtain flat images by calculating the time for obtaining flat images automatically and the exposure time using a numerically calculated function. When obtaining twilight flat images at dusk and at dawn, the developed program performs automated observation and provides effective flat images by acquiring appropriate exposure time considering the sunrise and sunset times that vary depending on the day of observation. The code for performing this task was added to Obs Tool II (Yoon et al. 2006), which is the automated observation system of the Chungbuk National University Observatory, and the usefulness of the developed program was examined by performing an actual automated observation. If this program is applied to other observatories where automated observation is in operation, it is expected that stable and highquality flat images could be obtained, which can be used for the pre-processing of photometric observation data

DOME ENCLOSURE: CLAM SHELL DESIGN

Near Earth Object Patrol Team (National Research Lab.) at KAO and YSTAR team at Yonsei University Observatory jointly developed a dome enclosure to be installed abroad together with a survey telescope. It has a fully-open clam shell type design to maximize the fast slew capability of the telescope and is also sturdy enough to protect the observation system under extreme weather conditions. We also developed an electric control circuit for the enclosure so that it can become a part of automated observing system. The enclosure has been installed at the Sutherland Observatory of South African Astronomical Observatory in April 2002, and has been successfully operational

Structural and Dynamical Properties of 29 Galactic Globular Clusters

We use B band CCD images to investigate the surface brightness distributions and dynamical properties of 29 Galactic globular clusters. Model fits suggest that 22 clusters show King type surface brightness profiles, while 7 clusters are characterized by power law cusp profiles. For the King type clusters, concentration parameters (c = log(r_t =r_c)) range from 1.20 to 2.10, and core radii are 0.4 to 1.9 pc. The mean value of power law slopes of 7 cuspy clusters was estimated as α = 1.011 ± 0.065. Total masses of King type globular clusters are in the range of 1.7 x 10^4 M⨀ to 1.0 x 10^6 M⨀ with a mean of 1.7 x 10^5 M⨀ . A significant positive correlation between mass and mass-to-light ratio of King type globular clusters has been confirmed with a Pearson's correlation coefficient r = 0.52 and a confidence level of 99%. Our data also confirm a linear relation between total mass and absolute magnitude of King type globular clusters