• Title/Summary/Keyword: airglow

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First Comparison of Mesospheric Winds Measured with a Fabry-Perot Interferometer and Meteor Radar at the King Sejong Station (62.2°S, 58.8°W)

  • Lee, Wonseok;Kim, Yong Ha;Lee, Changsup;Wu, Qian
    • Journal of Astronomy and Space Sciences
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    • v.35 no.4
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    • pp.235-242
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    • 2018
  • A Fabry-Perot interferometer (FPI) for mesospheric observations was installed at King Sejong Station ($62.2^{\circ}S$, $58.9^{\circ}W$) in Antarctica in 2017. For the initial validation of the FPI measurements, we compare neutral wind data recorded with the FPI with those from a Meteor Radar (MR) located nearby. The overall characteristics of the FPI and MR winds of both OH 892.0 nm (87 km) and OI 557.7 nm (97 km) airglow layers are similar. The FPI winds of both layers generally match the MR winds well on the observed days, with a few exceptions. The correlation analysis of the FPI and MR wind data shows that the correlation coefficients for the zonal winds at 87 and 97 km are 0.28 and 0.54, respectively, and those for the meridional winds are 0.36 and 0.54, respectively. Based on the assumption that the distribution of the airglow emissions has a Gaussian function with respect to the altitude, we calculated the weighted mean winds from the MR wind profile and compared them with the FPI winds. By adjusting the peak height and full width at half maximum of the Gaussian function, we determined the change of the correlation between the two winds. The best correlation for the OH and OI airglow layers was obtained at a peak height of 88-89 km and 97-98 km, respectively.

FIMS WAVELENGTH CALIBRATION VIA AIRGLOW LINE OBSERVATIONS (대기광 관측을 통한 과학기술위성 1호 원자외선분광기(FIMS)의 파장 보정)

  • Lee, Dae-Hee;Seon, Kwang-Il;Park, Jang-Hyun;Jin, Ho;Yuk, In-Soo;Nam, Uk-Won;Han, Won-Yong;Park, Jae-Woo;Lee, Ji-Na;Ryu, Kwang-Sun;Min, Kyoung-Wook
    • Journal of Astronomy and Space Sciences
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    • v.21 no.4
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    • pp.391-398
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    • 2004
  • Far-ultraviolet Imaging Spectrograph (FIMS) is the main payload of the Korea's first scientific micro satellite STSAT-1, which was launched at Sep. 27 2003 successfully. Major objective of FIMS is observing hot gas in the Galaxy in FUV bands to diagnose the energy flow models of the interstellar medium. Supernova remnants, molecular clouds, and Aurora emission in the geomagnetic pole regions are specific targets for pointing observation. Although the whole system was calibrated before launch, it is essential to perform on-orbit calibration for data analysis. For spectral calibration, we observed airglow lines in the atmosphere since they provide good spectral references. We identify and compare the observed airglow lines with model calculations, and correct the spectral distortion appeared in the detector system to improve the spectral resolution of the system.

PRODUCT10N OF KSR-III AIRGLOW PHOTOMETERS TO MEASURE MUV AIRGLOWS OF THE UPPER ATMOSPHERE ABOVE THE KOREAN PENINSULAR (한반도 상공의 고층대기 중간 자외선 대기광 측정을 위한 KSR-III 대기광도계 제작)

  • Oh, T.H.;Park, K.C.;Kim, Y.H.;Yi, Y.;Kim, J.
    • Journal of Astronomy and Space Sciences
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    • v.19 no.4
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    • pp.305-318
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    • 2002
  • We have constructed two flight models of airglow photometer system (AGP) to be onboard Korea Sounding Rocket-III (KSR-III) for detection of MUV dayglow above the Korean peninsular. The AGP system is designed to detect dayglow emissions of OI 2972${\AA}$, $N_2$ VK(0,6) 2780${\AA}$, $N_2$ 2PG 3150${\AA}$ and background 3070${\AA}$ toward the horizon at altitudes between 100 km and 300 km. The AGP system consists of a photometer body, a baffle an electronic control unit and a battery unit. The MUV dayglow emissions enter through a narrow band interference filter and focusing lens of the photometer, which contains an ultraviolet sensitive photomultiplier tube. The photometer is equipped with an in-flight calibration light source on a circular plane that will rotate at the rocket's apogee. A bane tube is installed at the entry of the photometer in order to block strong scattering lights from the lower atmosphere. We have carried out laboratory measurements of sensitivity and in-flight calibration light source for the AGP flight models. Although absolute sensitivities of the AGP flight models could not be determined in the country, relative sensitivities among channels are well measured so that observation data during rocket flight in the future can be analyzed with confidence.

Mesospheric Temperatures over Apache Point Observatory (32°N, 105°W) Derived from Sloan Digital Sky Survey Spectra

  • Kim, Gawon;Kim, Yong Ha;Lee, Young Sun
    • Journal of Astronomy and Space Sciences
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    • v.34 no.2
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    • pp.119-125
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    • 2017
  • We retrieved rotational temperatures from emission lines of the OH airglow (8-3) band in the sky spectra of the Sloan digital sky survey (SDSS) for the period 2000-2014, as part of the astronomical observation project conducted at the Apache Point observatory ($32^{\circ}N$, $105^{\circ}W$). The SDSS temperatures show a typical seasonal variation of mesospheric temperature: low in summer and high in winter. We find that the temperatures respond to solar activity by as much as $1.2K{\pm}0.8K$ per 100 solar flux units, which is consistent with other studies in mid-latitude regions. After the seasonal variation and solar response were subtracted, the SDSS temperature is fairly constant over the 15 year period, unlike cooling trends suggested by some studies. This temperature analysis using SDSS spectra is a unique contribution to the global monitoring of climate change because the SDSS project was established for astronomical purposes and is independent from climate studies. The SDSS temperatures are also compared with mesospheric temperatures measured by the microwave limb sounder (MLS) instrument on board the Aura satellite and the differences are discussed.

Search for Gravity Waves with n New All-sky Camera System

  • Kim, Yong-Ha;Chung, Jong-Kyun;Won, Yong-In;Lee, Bang-Yong
    • Ocean and Polar Research
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    • v.24 no.3
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    • pp.263-266
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    • 2002
  • Gravity waves have been searched for with a new all-sky camera system over Korean Peninsular. The all-sky camera consists of a 37mm/F4.5 Mamiya fisheye lens with a 180 dog field of view, interference filters and a 1024 by 1024 CCD camera. The all-sky camera has been tested near Daejeon city, and moved to Mt. Bohyun where the largest astronomical telescope is operated in Korea. A clear wave pattern was successfully detected in OH filter images over Mt. Bohyun on July 18, 2001, indicating that small scale coherent gravity waves perturbed OH airglow near the mesopause. Other wave features are since then observed with Na 589.8nm and OI 630.0nm filters. Since a Japanese all-sky camera network has already detected traveling ionospheric disturbances (TID) over the northeast-southwest range of Japanese islands, we hope our all-sky camera extends the coverage of the TID's observations to the west direction. We plan to operate our all-sky camera all year around to study seasonal variation of wave activities over the mid-latitude upper atmosphere.

KSR-III 과학탑재 시스템 개발

  • Hwang, Seung-Hyun;Kim, Jhoon;Chun, Young-Doo;Kim, Yong-Ha;Jang, Min-Hwan
    • Aerospace Engineering and Technology
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    • v.1 no.2
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    • pp.83-90
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    • 2002
  • This paper describes the development of scientific payload system onboard the KSR-III. The ozone detector(UVR), Langmuir electron probe(LEP), airglow photometer(AGP), and magnetometer(MAG) constitute this system. The purpose of the ozone detector is to measure the ozone density profile and the LEP measures the electron density and temperature in the ionosphere over the Korean Peninsula. The AGP detects airglow in the mesosphere over the Korean Peninsular. The MAG provides rocket attitude and the magnetic fluctuation information during the flight. With the developed payloads, the ground calibration tests and the environmental tests have been performed.

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