• 천문학회보
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• 제36권1호
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• pp.84.2-84.2
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• 2011

Astrophysical jets play important roles in many interesting astronomical phenomena, such as star formation, gamma-ray bursts, and active galactic nuclei. The jets are thought to be driven by rotating disks through magneto-centrifugal processes. However, quantitative understanding of the jet-driving mechanism has been difficult because examples showing rotation in both disk and jet are rare. One of the important quantities in the models of jet engine is the size of the jet-launching region. The bipolar jet of the NGC 1333 IRAS 4A2 protostar shows a lateral velocity gradient, which suggests that the SiO jet is rotating around its axis. The jet rotation is consistent with the rotation of the accretion disk. The disk-jet rotation kinematics suggests that the jet-launching region on the disk, or the outflow foot-ring, has a radius of about 2 AU, which supports the disk-wind models.

• 한국지구과학회지
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• 제33권2호
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• pp.183-199
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• 2012

종래의 지구과학 교과서에서는 대중 과학잡지를 비롯한 각종 언론 매체에서 자주 다루는 최신 천문 현상들에 대한 내용이 매우 부실하였다. 2009 개정 과학과 교육과정에서는 이러한 내용들을 적극 수용하자는 것이 주요 개정 방향 중 하나이다. 추가로, 천문학과 물리학의 깊은 연관성에도 불구하고 그동안 지구과학 교과에서는 현대 물리학의 개념, 물리 교과에서는 천문학과의 연관성에 대한 내용이 많이 다루어지지 않았다. 따라서 2009 개정 과학과 교육과정에서는 과학의 융합 개념을 강조하고 있다. 위의 두 가지를 모두 포함하는 분야들 중 하나로서 고에너지 천체의 격변광 현상을 들 수 있다. 본 연구는 e-Science를 이용한 천체 관측의 실시간 자료 전송 및 영상화를 소개하였다. 그 첫 단계의 실험으로서 우리는 국가 연구 교육 시험망의 하나인 KOREN을 이용한 국내 최초의 한 일간 천문 관측 자료의 대용량 자료 전송 실험을 실시하였다. 또한 천문학 및 천체물리학 관측 분야에서 활발하게 진행되는 세계 각국의 e-Science 분야들을 소개하고, 과학탐구활동 및 과학 대중화 활동과 어떻게 연결되어 진행되는지 소개하였다. 아직 걸음마 단계인 국내 천문 분야의 e-Science에 있어서 우리의 실험이 가지는 과학적 및 교육적 의미를 짚어보고, 머지않아 상용화될 Gbps급 인터넷 환경에 있어서 이와 같은 실험의 과학탐구활동 및 과학 대중화 활동에 있어서의 활용을 전망해 보았다.

• Journal of Astronomy and Space Sciences
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• 제22권3호
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• pp.311-328
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• 2005

본 연구에서는 예비 초등 교사들을 대상으로 달의 위상변화에 대한 정신모형과 그 모형에 영향을 주는 요소들을 조사하였다. 본 연구에 참여한 예비교사는 교육대 학교 1학년(22명)과 2학년(21명) 학생이다. 자료 수집은 지필 검사와 개별 면담을 통해 이루어졌다. 연구 결과, 예비 초등 교사들은 달의 위상변화에 대한 설명들이 과학적 모형과는 다른 합성 정신모형들을 가지고 있었으며, '가리기 이론'이 그들의 정신 모형에 가장 큰 영향을 미치는 것으로 나타났다. 또한 예비 초등 교사들이 갖는 천문현상의 합성 정신모형의 구조와 근원을 알아보기 위하여 그들의 정신 모형들을 형성하는 틀 이론과 특정 이론을 집중적으로 탐색하였다.

• Journal of Astronomy and Space Sciences
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• 제41권2호
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• pp.107-119
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• 2024

It is known that Chang-Hwa Park (1889-1962) transcribed a chronicle of the Goguryeo kingdom (BC 37-AD 668) of Korea (hereafter Goguri annal) from literature of the time that is no longer available. However, the authenticity of his transcription remains disputed. This study attempts to verify whether the Goguri annal is a pseudograph by analyzing the astronomical records in the annal. Although the Goguryeo kingdom fell in the year 668, the Goguri annal contains records up to the year 536. In this study, we have classified the astronomical records into eight categories and clustered them into two groups: a calendrical data group of reign-name and calendar date categories, and a celestial phenomena group of solar eclipse, trespass, comet, daylight appearance of Venus, meteor/meteorite, and other categories. The records of each category have been compared with those of the Samguksagi (History of the Three Kingdoms), Chinese chronicles, and with the results of modern computations wherever possible. From this comparison, we have not found any critical record that would indicate that the Goguri annal is a pseudograph, although the same astronomical records, with the exception of a few, are also found in the Samguksagi and Chinese chronicles.

• 천문학회지
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• 제37권5호
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• pp.447-454
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• 2004

During the hierarchical formation of large scale structure in the universe, the progressive collapse and merging of dark matter should inevitably drive shocks into the gas, with nonthermal particle acceleration as a natural consequence. Two topics in this regard are discussed, emphasizing what important things nonthermal phenomena may tell us about the structure formation (SF) process itself. 1. Inverse Compton gamma-rays from large scale SF shocks and non-gravitational effects, and the implications for probing the warm-hot intergalactic medium. We utilize a semi-analytic approach based on Monte Carlo merger trees that treats both merger and accretion shocks self-consistently. 2. Production of $^6Li$ by cosmic rays from SF shocks in the early Galaxy, and the implications for probing Galaxy formation and uncertain physics on sub-Galactic scales. Our new observations of metal-poor halo stars with the Subaru High Dispersion Spectrograph are highlighted.

• 천문학회지
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• 제29권spc1호
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• pp.451-453
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• 1996

There is a question, 'Which is beautiful, a flower or a star?'. Its answer is different from one person .to another. It is only a matter of what one is interested in. It is very difficult for most school pupils, who will have non-scientific jobs, to understand science courses taught currently in school, because each science (physics, chemistry, biology, and earth science) is independently taught from the other sciences. Therefore, their knowledge of sciences obtained during their school period does not significantly help their understanding of global environmental problems. I am proposing that several scientific stories should be prepared to connect all the related scientific phenomena in order to give those pupils ideas in understanding global environmental problems. I believe that astronomy is able to play an important role in this context.

• 천문학회보
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• 제42권2호
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• pp.75.3-75.3
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• 2017

We Investigate dust stripping of Virgo cluster galaxies that are known to suffer HI gas stripping. The gas stripping phenomena of these galaxies may result from either ram pressure induced by the hot intracluster medium or gravitational tidal interactions between galaxies. While much efforts have been made to directly detect gas removed from cluster galaxies, the spatial distributions of dust, which should also be affected, are hardly known. Several previous studies have tried to directly detect the morphology of gas or dust using radio or infrared observations, but such approaches are hard to widely apply because of the limit of observational resolution and sensitivity. In this study, we try a different approach using optical data: measuring the background galaxy reddening by the dust stripped from the Virgo cluster members. Based on optical color excess maps of the background galaxies, we compare the ambient dust distribution with the HI morphology of the Virgo galaxies. We discuss how efficiently dust stripping can be detected with this method and how the stripped dust is associated with the removed gas according to HI gas stripping stage over the sample.

• 천문학회보
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• 제42권2호
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• pp.65.5-66
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• 2017

In the history of astronomy, observed data were interpreted very frequently based upon data measured at laboratories. For example, all the spectroscopic observations were understood via spectroscopic measurements on nuclei, atoms, and molecules. Recently, computational astrophysics plays a role of bridging experimental data to observations, in particular via numerical modeling of complex astronomical phenomena. This presentation focuses on computational nuclear astrophysics that connects experimental data on nuclei to high-energy observation data obtained by X-ray and gamma-ray telescopes. As an example case, X-ray burst will be discussed. In this phenomenon, observed X-ray light curves and spectra can be modeled by stellar evolution calculations that take nuclear reactions of rare isotopes as input information. This presentation also works as an introduction to the following presentation that will provide more detailed discussion on the experimental aspect of X-ray burst.

• 천문학논총
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• 제19권1호
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• pp.65-70
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• 2004

An imaging spectrograph concept optimized for extended far-ultraviolet emission sources is presented. Although the design was originally developed for FIMS aboard the first Korean science satellite STSAT-l launched on September 27, 2003, no rigorous theoretical background of the spectrograph design has been published. The spectrograph design employs an off-axis parabolic cylinder mirror in front of a slit that guides lights to a diffraction grating. The concave grating provides moderate spatial resolution over a large field of view. This mapping capability is absent in most astronomical instruments but is crucial to the understanding of the nature of a variety of astrophysical phenomena. The aberration theory presented in this paper can be extended to holographic gratings in order to improve the spatial as well as the spectral resolutions.

• 천문학회보
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• 제41권1호
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• pp.31.3-31.3
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• 2016

Exploring a universe with gravitational waves (GWs) was only theoretical expectation for long time. In September 2015, the Laser Interferometer GW Observatory (LIGO) first detected GWs emitted from the collision of two stellar-mass black holes in cosmological distance (1.3 billion light years) on Earth. This confirms the existence of black-hole binary mergers, and further, opens a new field of GW astronomy. We begin our discussion with a list of important GW sources that can be detectable on Earth by large-scale laser interferometers such as LIGO. Focusing on compact objects such as neutron stars and black holes, we then discuss possible research in the context of GW astronomy. By coordinating with existing observatories, searching for electromagnetic waves or particles from astronomical objects, around the world, multi-messenger astronomy for the universe's most cataclysmic phenomena (e.g. gamma-ray bursts) will be available in the near future.