| Summary: | A new ground-based optical observation of aurora and airglow in short-wavelength infrared (SWIR) of 1.05-1.35 μm has been initiated at The Kjell Henriksen Observatory (KHO), Longyearbyen (78.1°N, 16.0°E) since November 2022. Two state-of-the-art instruments, a SWIR imaging spectrograph and a monochromatic imager, are being operated to focus on study on dayside magnetosphere-ionosphere-atmosphere coupling processes in the high polar regions.The 2-D imaging spectrograph, NIRAS-2, measures SWIR auroral emissions such as N2+ Meinel band (0,0), N2 1st Positive bands (0,1), and OI- line with time resolution of 30 seconds. Using high spectral resolution mode, N2+ ion rotational temperature would be estimated. For upper mesosphere, OH (8,5) band was measured and its rotational temperature can be estimated with10-min resolutions and errors less than 5 K. In addition, one more important thing is that this OH emission band is almost completely uncontaminated by aurora. On the other hand, the brand-new SWIR camera, NIRAC, can visualize two-dimensional structures of not only aurora (N2+) but also even weak airglow (OH) with a cadence of less than 30 seconds. This is the monochromatic imaging of SWIR aurora for the first time so far, and the NIRAC is used as a twin instrument to the NIRAS-2 to help in interpreting meridional scan data obtained from the NIRAS-2. Taking geographical advantage of the observatory, 24-hours continuous observations can be expected near the winter solstice. Initial results of NIRAS-2 and NIRAC are presented and then we will discuss the observational strategies and future collaborations.
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