• 천문학논총
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• 제27권4호
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• pp.201-207
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• 2012

Following the first Public Release of the AKARI Point Source catalogues, we have worked on the production of a new far-infrared All-Sky Diffuse mapping product. In this paper we report first results from the All Sky diffuse maps that will shortly be released to the community, based on analysis of data from the Far Infrared Surveyor ($65{\mu}m-160{\mu}m$) instrument. These data are likely to have a strong impact on studies of extended structures, and the diffuse ISM.

• 한국지구과학회지
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• 제45권2호
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• pp.147-156
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• 2024

과학 실천은 학습 소재에 해당하는 대상이나 관찰과 측정을 위한 도구와 같은 '이질적인 것'들과 새로운 관계를 맺는 과정이다. 최근 전공 교과에 대한 과학 실천이 점차 강조되고 있는 시점에서 본 연구에서는 천체 관측이라는 지구과학 교과의 특유한 과학 실천을 새롭게 들여다보고자 했다. 이를 위해 천체 관측을 경험한 학생들과 수많은 물질들이 만들어 낸 의미를 '-되기'의 경험으로 바라보았다. 연구의 방법으로는 A고등학교의 천체 관측 활동에 참여하는 17명의 학생들이 작성한 활동 일지, 사진 자료 등을 수집하고 심층 면담을 진행하였다. 수집한 자료는 상황 분석 방법을 재구성하여 살펴보았다. 주요 연구결과로는, 학생들의 존재-인식론적 '-되기'의 과정으로 1) 반복을 통해 새로움을 발견하는 과정, 2) 천체 관측 활동의 정동을 전달하기 위한 '설명 기계'가 되어가는 과정, 3) 안정적인 영토를 벗어나 문턱을 넘는 과정을 발견하였다. 연구 결과를 바탕으로 지구과학교육과 교육 연구를 위한 교사의 실천과 새로운 접근 방식에 대해 제언하였다.

• 천문학회지
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• 제52권1호
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• pp.23-30
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• 2019

The KVN(Korean VLBI Network)-style simultaneous multi-frequency receiving mode is demonstrated to be promising for mm-VLBI observations. Recently, other Very long baseline interferometry (VLBI) facilities all over the globe start to implement compatible optics systems. Simultaneous dual/multi-frequency VLBI observations at mm wavelengths with international baselines are thus possible. In this paper, we present the results from the first successful simultaneous 22/43 GHz dual-frequency observation with KaVA(KVN and VERA array), including images and astrometric results. Our analysis shows that the newly implemented simultaneous receiving system has brought a significant extension of the coherence time of the 43 GHz visibility phases along the international baselines. The astrometric results obtained with KaVA are consistent with those obtained with the independent analysis of the KVN data. Our results thus confirm the good performance of the simultaneous receiving systems for the nonKVN stations. Future simultaneous observations with more global stations bring even higher sensitivity and micro-arcsecond level astrometric measurements of the targets.

• 천문학논총
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• 제12권1호
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• pp.47-62
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• 1997

In this paper we present a newly improved telescope control software and a newly developed data analysis software package for effective use of the Solar Flare Telescope(SOFT) The telescope control software permits us to make not only auto tacking of the SOFT, but also quantitative measurement of the solar irradiation, allowing us to provide weather monitorings. In addition we introduce an IDL widget software package for both monochromatioc (MONO version) and polarimetric data (VMG version) analysis. The MONO version is capable of loading FITS files, changing colors and contrast, image processing, displaying plots, and saving displayed plots by selected formats The VMG version, on the other hand provides a calibration of polarimetric data and plots of reduced vector magnetic fields.

• 천문학논총
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• 제12권1호
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• pp.185-196
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• 1997

We present a code which identifies individual clouds in crowded region using IMFORT interface within Image Reduction and Analysis Facility (IRAF). We define a cloud as an object composed of all pixels in longitude, latitude, and velocity that are simply connected and that lie above some threshold temperature. The code searches the whole pixels of the data cube in efficient way to isolate individual clouds. Along with identification of clouds it is designed to estimate their mean values of longitudes, latitudes, and velocities. In addition, a function of generating individual images (or cube data) of identified clouds is added up. We also present identified individual clouds using a $^{12}CO$ survey data cube of Galactic Anticenter Region (Lee et al. 1997) as a test example. We used a threshold temperature of $5\sigma$ rms noise level of the data With a higher threshold temperature, we isolated subclouds of a huge cloud identified originally. As the most important parameter to identify clouds is the threshold value, its effect to the size and velocity dispersion is discussed rigorously.

• 천문학회보
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• 제39권2호
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• pp.64.1-64.1
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• 2014

We study the dust and star-formation characteristics of a nearby dwarf elliptical galaxy, NGC 855. With various archival data from ultraviolet to far-infrared, we build up the spectral energy distribution (SED) that can give us constraints on stellar populations, dust characteristics, star-formation history, etc. From GALEX and SDSS data, slightly de-centered bluer central core is confirmed, where star formation might take place. This regions is coincident with seemingly dis-integrated cores detected by Spitzer IRAC data and with bright Ha feature observed at ground-based telescope. The PACS and SPIRE data by Herschel Space Observatory show the dominant dust features at the center. Lastly, we propose necessary follow-up observations with ground-based telescopes to investigate spectral properties of NGC 855.

• 천문학회지
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• 제29권spc1호
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• pp.23-24
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• 1996

We reexamined CDM texture large-scale structure (LSS) formation model. We confirmed that texture model is consistent with 4-year COBE data both in an open and a critical matter density (${\Omega}_0$ = 1) universes, and then obtained normalization for density perturbation power spectrum. We next compare the power spectrum with LSS observation data. Contrary to the previous literature, we found that texture model matches with these data in an open universe no better than in an ${\Omega}_0$ = 1 universe. We also found that the model is more likely to fit these data in a cosmological constant dominated ($\Lambda-$) universe.

• 천문학회보
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• 제35권2호
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• pp.63.1-63.1
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• 2010

CQUEAN (Camera for QUasars in EArly uNiverse) is a newly developed camera system by CEOU optimized at 0.8 - $1.1{\mu}m$ wavelength region. From Aug. 10 to Aug. 17, 2010, the camera was installed at 2.1m Otto Struve telescope at McDonald Observatory, USA, and engineering test observation was performed. We obtained the data for the characteristics of camera and scientific purpose using 7 filters (g, r, i, z, Is, Iz, Y). For the purpose of discovery of z - 5~6 quasar, we specially used new filters (Is,Iz). During the test observation, we obtained the data of Gamma-Ray Burst, high redshift quasars, high redshift quasar candidates and other calibration data. We present general characteristics of the reduced data taken with CQUEAN and show the performance of the camera.

• 천문학논총
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• 제24권1호
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• pp.83-91
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• 2009

We have designed data processing server system to include data archiving, photometric processing and light curve analysis for KMTNet (Korea Microlensing Telescope Network). Outputs of each process are reported to the main photometric database, which manages the whole processing steps and archives the photometric results. The database is developed using ORACLE 11g Release 2 engine. It allows to select objects applying any set of criteria such as RA/DEC coordinate and Star ID, etc. We tested the performance of the database using the OGLE photometric data. The searching time for querying 70,000,000 records was under 1 second. The database is fully accessed using query forms via web page.

• 천문학회보
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• 제36권2호
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• pp.101.1-101.1
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• 2011

National Meteorological Satellite Center(NMSC) of Korea Meteorological Administration(KMA) is collecting GNSS data in near-real time for about 80 GNSS stations operated by multiple agencies. (eg. National Geographic Information Institute (NGII), Korea Astronomy and Space Science Institute (KASI), DGNSS Central Office) Using these GNSS data, NMSC developed automatic Total Electron Contents(TEC) derivation system over the Korean peninsular every 1-hour based on single station data processing. We present the TEC result and validation of TEC using International GNSS Service(IGS) global TEC data for the case of quiet time and storm time. The future plans for the system improvement will be discussed.