17:15 〜 19:15
[PEM13-P08] LAMP2ロケット搭載オーロラカメラ開発およびシーボトムにおける地上観測報告
キーワード：脈動オーロラ、マイクロバースト、ロケット、大気流出、中層大気
The LAMP-1 rocket was successfully launched into active pulsating auroral patches from Poker Flat Research Range at 11:27:30 UT on March 5, 2022. Two auroral cameras AIC1 and 2 worked satisfactorily throughout the flight, and we got the successive auroral images at two wavelengths at N2 1PG (670nm) and OI (845nm). Following the success of the LAMP-1 rocket campaign, the new LAMP-2 rocket has been proposed to NASA, which is planned to be launched in the winter of 2027 into the vicinity of field-of-view of IS radar, and we are currently waiting for the approval.
Although the cameras on LAMP-1 succeeded to observe pulsating auroral continuously, the faster imaging and higher sensitivity are required to resolve the internal modulation (~3Hz) and to observe the faint emission of oxygen 845 nm. In addition, the LAMP-1 cameras adopted the rolling shutter CMOS which might not be appropriate for high-time variation of pulsating aurora in a frame. For the LAMP-2 rocket mission, we designed new auroral cameras AIC1 and 2 with a sampling of 15 frame/s (fps) which is 1.5 times faster than LAMP-1 cameras. We selected a new-generation global shutter CMOS sensor (ASI-432MM, 1.1") which has larger than LAMP-1/AIC (ASI-183MM, 1"). Using the LED array blinked with an external clock signal, we confirmed the time accuracy of captured image frame which is sufficient even at 20 fps (50 ms exposure). We also checked that the global shutter characteristics and found that the time difference between top and bottom of image is negligible (3 ms ± 0.9 ms).
Following these laboratory experiments, we fabricated the engineering model (EM) of AIC1 and 2, which has the same lens, filter, and CMOS sensor, and installed them on the Optical Field Station at Skibotn (Glat: 69.4 deg, GElon: 20.3 deg), one of the EISCAT_3D radar base stations, in September 2024. In addition, we installed a monochromatic all-sky camera to observe continuous auroral image at 845nm every 18s. AIC1-EM (670nm) and AIC2-EM (845nm) observe auroral image at the zenith with a FOV of 30 x 30 deg. and 106 deg. circle, respectively, with 15 fps. AIC1-EM and AIC2-EM are operated for 10 minutes from 00 min to 10 min every hour on each night using cronjob. We can remotely control the operation system of cameras and checked the status almost every day from Japan.
From the initial analysis, AIC1-EM and AIC-2 EM succeeded to observe the bright discrete auroras, however, only AIC1-EM observed pulsating auroras. Considering the faint emission of 845nm aurora, we are now discussing the change of filter of AIC2 from 845nm to N2+ 428nm because the sunlit emission of N2+ would be useful to investigate the N2+ ion upflow possibly caused by the ionospheric heating associated with pulsating aurora. Therefore, we will visit Skibotn Station in the mid-February and change the filter of AIC2-EM to 428nm to examine the effectiveness of 428nm data for AIC2-EM. In this presentation, we give the current status of the development of LAMP-2/AIC1 and 2, and results of auroral image data taken by AIC1-EM and AIC2-EM at Skibotn.
Although the cameras on LAMP-1 succeeded to observe pulsating auroral continuously, the faster imaging and higher sensitivity are required to resolve the internal modulation (~3Hz) and to observe the faint emission of oxygen 845 nm. In addition, the LAMP-1 cameras adopted the rolling shutter CMOS which might not be appropriate for high-time variation of pulsating aurora in a frame. For the LAMP-2 rocket mission, we designed new auroral cameras AIC1 and 2 with a sampling of 15 frame/s (fps) which is 1.5 times faster than LAMP-1 cameras. We selected a new-generation global shutter CMOS sensor (ASI-432MM, 1.1") which has larger than LAMP-1/AIC (ASI-183MM, 1"). Using the LED array blinked with an external clock signal, we confirmed the time accuracy of captured image frame which is sufficient even at 20 fps (50 ms exposure). We also checked that the global shutter characteristics and found that the time difference between top and bottom of image is negligible (3 ms ± 0.9 ms).
Following these laboratory experiments, we fabricated the engineering model (EM) of AIC1 and 2, which has the same lens, filter, and CMOS sensor, and installed them on the Optical Field Station at Skibotn (Glat: 69.4 deg, GElon: 20.3 deg), one of the EISCAT_3D radar base stations, in September 2024. In addition, we installed a monochromatic all-sky camera to observe continuous auroral image at 845nm every 18s. AIC1-EM (670nm) and AIC2-EM (845nm) observe auroral image at the zenith with a FOV of 30 x 30 deg. and 106 deg. circle, respectively, with 15 fps. AIC1-EM and AIC2-EM are operated for 10 minutes from 00 min to 10 min every hour on each night using cronjob. We can remotely control the operation system of cameras and checked the status almost every day from Japan.
From the initial analysis, AIC1-EM and AIC-2 EM succeeded to observe the bright discrete auroras, however, only AIC1-EM observed pulsating auroras. Considering the faint emission of 845nm aurora, we are now discussing the change of filter of AIC2 from 845nm to N2+ 428nm because the sunlit emission of N2+ would be useful to investigate the N2+ ion upflow possibly caused by the ionospheric heating associated with pulsating aurora. Therefore, we will visit Skibotn Station in the mid-February and change the filter of AIC2-EM to 428nm to examine the effectiveness of 428nm data for AIC2-EM. In this presentation, we give the current status of the development of LAMP-2/AIC1 and 2, and results of auroral image data taken by AIC1-EM and AIC2-EM at Skibotn.