AM
A. Mathieu
info
Please Note
<p>This page displays the records of the person named above and is not linked to a unique person identifier. This record may need to be merged to a profile.</p>
2 records found
1
Uncovering Peculiar Rainbows
Automated Detection and Characterisation of Luminous Bands in Saturn's E Ring
Saturn's E ring harbours faint, quasi-periodic, inclined brightness structures called luminous bands, first characterised from Cassini VIMS and ISS observations during Enceladus flybys. We present the first automated, catalogue-scale survey of luminous bands, drawing on 23 Cassini flybys. Detection exploits the chromatic character of the bands, whose apparent position shifts with wavelength. Because these bands present a quasi-periodic inclined brightness structure, a frequency-domain search using a zero-padded two-dimensional Fourier angular spectrum is applied, with candidates assessed against a phase-randomised null ensemble. Of 573 processed images, 62 yield positive detections across eight flybys. Six of the eight carry no prior published detection, including the first ISS detection for E13, and five are non-targeted flybys, demonstrating bands are present in more ISS images than initially found. The observed band directions are compared against a diffraction model: 39 of the 62 detections agree to within 2 degrees, confirming the grating interpretation; the remaining 23 show a systematic offset whose origin is not yet explained. Band contrasts decrease with Cassini–Enceladus distance, suggesting the strongest structure near the plume source. Notably, no detections occur in the morning ansa despite comparable coverage. A complementary VIMS spectral analysis reveals selective suppression of sub-micron grains on the morning-side ring, consistent with size-selective electromagnetic clearing by Lorentz forces, explaining the asymmetric detection rate.
...
Saturn's E ring harbours faint, quasi-periodic, inclined brightness structures called luminous bands, first characterised from Cassini VIMS and ISS observations during Enceladus flybys. We present the first automated, catalogue-scale survey of luminous bands, drawing on 23 Cassini flybys. Detection exploits the chromatic character of the bands, whose apparent position shifts with wavelength. Because these bands present a quasi-periodic inclined brightness structure, a frequency-domain search using a zero-padded two-dimensional Fourier angular spectrum is applied, with candidates assessed against a phase-randomised null ensemble. Of 573 processed images, 62 yield positive detections across eight flybys. Six of the eight carry no prior published detection, including the first ISS detection for E13, and five are non-targeted flybys, demonstrating bands are present in more ISS images than initially found. The observed band directions are compared against a diffraction model: 39 of the 62 detections agree to within 2 degrees, confirming the grating interpretation; the remaining 23 show a systematic offset whose origin is not yet explained. Band contrasts decrease with Cassini–Enceladus distance, suggesting the strongest structure near the plume source. Notably, no detections occur in the morning ansa despite comparable coverage. A complementary VIMS spectral analysis reveals selective suppression of sub-micron grains on the morning-side ring, consistent with size-selective electromagnetic clearing by Lorentz forces, explaining the asymmetric detection rate.
Ouranos Mission
A mission to the Uranian system for in-situ atmospheric measurements
Bachelor thesis
(2023)
-
A. Mathieu, A.M.N. Van Der Steichel, D.V.M. Lappee, E. Dalla Piazza, F.R. Lagarden, J.A. Dijkstra, M. Zambolin, N. Kaijser, P. Rinaldi Meneses, S.M.W. Nuijten, E. Mooij, E. van Kampen, E.T.B. Smeets
With the alignment of the planets in the 2030s, a perfect opportunity is presented to explore the outer reaches of the Solar System. With this, studying Uranus would become possible. With it being one of the least studied planets in the Solar System, the demand for accurate scientific data is high. This is where Ouranos comes in. This project has the specific purpose to design a scientific mission to Uranus, where measurements will be taken of its atmosphere. The summary below highlights the important parts and results of this report.
...
With the alignment of the planets in the 2030s, a perfect opportunity is presented to explore the outer reaches of the Solar System. With this, studying Uranus would become possible. With it being one of the least studied planets in the Solar System, the demand for accurate scientific data is high. This is where Ouranos comes in. This project has the specific purpose to design a scientific mission to Uranus, where measurements will be taken of its atmosphere. The summary below highlights the important parts and results of this report.