JIRAM (Jupiter Infrared Auroral Mapper) is the infrared imaging spectrometer on board the NASA-ASI Juno mission. JIRAM is equipped by a spectrometer and two image channels operating in the spectral regions centred at 3.46 mm(band-pass filter L) and 4.78 mm(band-pass filter M). The data acquired on 2017 July 17 through the M-channel (hereafter imager-M) in the Jupiter North Equatorial Belt (NEB) revealed a wide region (50W-90E System III longitudes) perturbed by a wave pattern. The whole pattern is covered in three successive acquisition of the imager-M. The wave train looks not uniform in direction and covers a latitude range of 3 degree about between 13° and 16° N. We use a wavelet analysis to infer an average wavelength for each JIRAM image and try a preliminary vertical location of the waves pressure level, by comparing the thermal brightness values of the images with the Galileo probe temperature profile (Seiff et al., 1998), taking advantage of the presence of some hot spots in the same field of view of the wave pattern. We found an average wavelength of ~1700 km and a pressure level approximately of 2.2 bar for the cloud tops marking the wave peaks.
Characterization of the gravity waves in the Jupiter NEB by JIRAM images
Moriconi ML;
2018
Abstract
JIRAM (Jupiter Infrared Auroral Mapper) is the infrared imaging spectrometer on board the NASA-ASI Juno mission. JIRAM is equipped by a spectrometer and two image channels operating in the spectral regions centred at 3.46 mm(band-pass filter L) and 4.78 mm(band-pass filter M). The data acquired on 2017 July 17 through the M-channel (hereafter imager-M) in the Jupiter North Equatorial Belt (NEB) revealed a wide region (50W-90E System III longitudes) perturbed by a wave pattern. The whole pattern is covered in three successive acquisition of the imager-M. The wave train looks not uniform in direction and covers a latitude range of 3 degree about between 13° and 16° N. We use a wavelet analysis to infer an average wavelength for each JIRAM image and try a preliminary vertical location of the waves pressure level, by comparing the thermal brightness values of the images with the Galileo probe temperature profile (Seiff et al., 1998), taking advantage of the presence of some hot spots in the same field of view of the wave pattern. We found an average wavelength of ~1700 km and a pressure level approximately of 2.2 bar for the cloud tops marking the wave peaks.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
