Space Environment Laboratory

Seoul, South Korea

Space Environment Laboratory

Seoul, South Korea

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Kil H.,Johns Hopkins University | Kwak Y.-S.,Korea Astronomy and Space Science Institute | Lee W.K.,Korea Astronomy and Space Science Institute | Oh S.-J.,Space Environment Laboratory | And 2 more authors.
Journal of Geophysical Research: Space Physics | Year: 2014

We investigated the association of broad plasma depletions (BPDs) with plasma bubbles and ionospheric uplift in the equatorial F region using the coincident satellite and radar observations over Jicamarca in Peru. BPDs were detected by the first Republic of China satellite (ROCSAT-1) on the nights of 21 and 22 December 2002 during the period of moderate geomagnetic activity. The observations of the Jicamarca Unattended Long-term Investigations of the Ionosphere and Atmosphere radar and an ionosonde showed that the F peak height was lifted above the ROCSAT-1 altitude (600 km) at the times of the BPD detection. The fraction of NO+ was substantial at the locations of BPDs. These observations support the association of the BPDs with the ionospheric uplift. However, the absence of large backscatter plumes at the times of the BPD detection indicates that the BPDs were not produced by a single large bubble or a merger of bubbles. Key Points Broad plasma depletions (BPDs) are the bottomside phenomena BPDs are not associated with the evolution of plasma bubbles Ionospheric uplift is responsible for the satellite detection of BPDs ©2014. American Geophysical Union. All Rights Reserved.


Park C.,Korea Astronomy and Space Science Institute | Jaffe D.T.,University of Texas at Austin | Yuk I.-S.,Korea Astronomy and Space Science Institute | Chun M.-Y.,Korea Astronomy and Space Science Institute | And 29 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

The Immersion Grating Infrared Spectrometer (IGRINS) is a compact high-resolution near-infrared cross-dispersed spectrograph whose primary disperser is a silicon immersion grating. IGRINS covers the entire portion of the wavelength range between 1.45 and 2.45μm that is accessible from the ground and does so in a single exposure with a resolving power of 40,000. Individual volume phase holographic (VPH) gratings serve as cross-dispersing elements for separate spectrograph arms covering the H and K bands. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is 1″ × 15″ and the plate scale is 0.27″ pixel. The spectrograph employs two 2048 × 2048 pixel Teledyne Scientific and Imaging HAWAII-2RG detectors with SIDECAR ASIC cryogenic controllers. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be only 25mm, which permits a moderately sized (0.96m × 0.6m × 0.38m) rectangular cryostat to contain the entire spectrograph. The fabrication and assembly of the optical and mechanical components were completed in 2013. We describe the major design characteristics of the instrument including the system requirements and the technical strategy to meet them. We also present early performance test results obtained from the commissioning runs at the McDonald Observatory. © 2014 SPIE.


Kil H.,Johns Hopkins University | Lee W.K.,University Corporation for Atmospheric Research | Kwak Y.-S.,Korea Astronomy and Space Science Institute | Oh S.-J.,Space Environment Laboratory | And 2 more authors.
Journal of Geophysical Research: Space Physics | Year: 2012

Various longitudinal wave patterns exist in the low-latitude ionosphere, but the investigation has been limited to the wave number (WN) 3 and 4 patterns. This study extends the investigation to the wave patterns that have not yet been explored. The persistent ionospheric wave patterns are investigated by using the measurements of the ion density during March 1999-June 2004 by the first Republic of China satellite. The investigation is performed with data sets in the magnetic south (20S-0) and magnetic north (0-20N). The dominant wave features in plasma density are the WN1, WN2, WN3, and WN4 patterns. Among them, the WN1 pattern in the magnetic south during the June solstice is the most pronounced feature. Except for this component, the WN3 pattern is the most persistent and pronounced feature. Fundamental difference exists between the WN1 and WN2 patterns and the WN3 and WN4 patterns. First, the wave phases in the south and north are the same in the WN3 and WN4 patterns, but they are opposite in the WN1 and WN2 patterns. Second, the amplitudes of the WN3 and WN4 patterns show similar annual variation in the south and north, but those of the WN1 and WN2 patterns show opposite annual trends in the opposite hemispheres. These observations indicate that the WN1 and WN2 patterns and the WN3 and WN4 patterns are created by different mechanisms. We discuss the creation of the WN1 and WN2 patterns in association with the geomagnetic field configuration. © 2012. American Geophysical Union. All Rights Reserved.


Tobiska W.K.,Utah State University | Crowley G.,ASTRA | Oh S.J.,Space Environment Laboratory | Guhathakurta M.,NASA
Space Weather | Year: 2010

True to the saying that "a picture is worth a thousand words," society's affinity for visual images has driven innovative efforts to see space weather as it happens. The newest frontiers of these efforts involve applications, or apps, on cellular phones, allowing space weather researchers, operators, and teachers, as well as other interested parties, to have the ability to monitor conditions in real time with just the touch of a button. Copyright 2010 by the American Geophysical Union.


Tobiska W.K.,Utah State University | Crowley G.,ASTRA | Oh S.J.,Space Environment Laboratory | Guhathakurta M.,Heliophysics Division
Space Weather | Year: 2011

A URL was given incorrectly in the article "Space weather gets realon smartphones" (Tobiska, W. K., G. Crowley, S. J. Oh, and M. Guhathakurta, Space Weather, 8, S10006, doi:10.1029/2010SW000619). In the penultimate paragraph of the "Developing Smartphone Apps" section, the correct URL for the integrated Space Weather Analysis System (iSWA) is http://iswa.gsfc. nasa.gov. Copyright 2010 by the American Geophysical Union.

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