PPARCセミナー(2024/07/22)

PPARCセミナー(2024/07/22)

(1)
[Name] Rikuto Yasuda

[Title]
Remote sensing of Jupiter’s Icy Moon Ionosphere with Jovian Auroral Radio Waves

[Abstract]
The ionospheres of Jupiter’s icy moons have been observed by in situ plasma measurements and radio science. However, their spatial structures have not yet been fully characterized. To address this, we developed a new ray tracing method for modeling the radio occultation of the ionospheres using Jovian auroral radio sources. We applied our method to Jovian auroral radio observations with the Galileo spacecraft and derived the electron density of the ionosphere of Ganymede and Callisto. This method is also applicable to upcoming Jovian radio observation data from the Jupiter Icy Moon Explorer, JUICE. Today, I would like to report on the calibration work of the JUICE RPWI, which is essential for future applications.

(2)
[Name] Takeshi Sakanoi

[Title]
Auroral height profiles obtained with the LAMP1 rocket/AIC and observation plan of the LAM2 rocket

[Abstract]
I give a talk on the recent results of a multi-spectral auroral camera AIC on the NASA’s LAMP rocket launched from Poker Flat at 11:27:30 UT on March 5, 2022. From the AIC2 data, we estimated the altitude distribution of oxygen 845nm emission with the following three methods. (1) Altitude difference of emission intensities in the direction of the magnetic footprint. (2) Time series of emission intensity in the horizontal direction during the flight. From these analyses, we estimated the emission peaks in the altitude range from 160km to 330km, and emission existed even in the altitude of 100-200 km. The estimated emission altitudes are consistent with the electron precipitation in the energy range of a few keV obtained by EPLAS onboard the rocket.
For the LAMP2 rocket mission which is planned to be launched in the winter of 2026, we are now developing a new AIC with a sampling of 15 frame/s. We selected a large-sized CMOS (ASI-432MM, 1.1″, global shutter) which has higher capabilities than LAMP/AIC (ASI-183MM, 1″, rolling shutter). We plan to carry out test observation with the engineering model of LAMP2/AIC1 and AIC2 at Skibotn during this winter period. The current status of the instruments and observation plan will be given in this talk.