Please use this identifier to cite or link to this item:
|Title:||Jupiter's Mesoscale Waves Observed at 5 mu m by Ground-based Observations and Juno JIRAM|
|Authors:||Fletcher, Leigh N.|
Simon, A. A.
Donnelly, P. T.
Orton, G. S.
Wong, M. H.
Moriconi, M. L.
|Publisher:||American Astronomical Society, IOP Publishing|
|Citation:||Astronomical Journal, 2018, 156 (2)|
|Abstract:||We characterize the origin and evolution of a mesoscale wave pattern in Jupiter's North Equatorial Belt (NEB), detected for the first time at 5 μm using a 2016–17 campaign of "lucky imaging" from the VISIR instrument on the Very Large Telescope and the NIRI instrument on the Gemini observatory, coupled with M-band imaging from Juno's JIRAM instrument during the first seven Juno orbits. The wave is compact, with a 1fdg1–1fdg4 longitude wavelength (wavelength 1300–1600 km, wavenumber 260–330) that is stable over time, with wave crests aligned largely north–south between 14°N and 17°N (planetographic). The waves were initially identified in small (10° longitude) packets immediately west of cyclones in the NEB at 16°N but extended to span wider longitude ranges over time. The waves exhibit a 7–10 K brightness temperature amplitude on top of an ~210 K background at 5 μm. The thermal structure of the NEB allows for both inertio-gravity waves and gravity waves. Despite detection at 5 μm, this does not necessarily imply a deep location for the waves, and an upper tropospheric aerosol layer near 400–800 mbar could feature a gravity wave pattern modulating the visible-light reflectivity and attenuating the 5-μm radiance originating from deeper levels. Strong rifting activity appears to obliterate the pattern, which can change on timescales of weeks. The NEB underwent a new expansion and contraction episode in 2016–17 with associated cyclone–anticyclone formation, which could explain why the mesoscale wave pattern was more vivid in 2017 than ever before.|
|Rights:||Copyright © 2018, American Astronomical Society, IOP Publishing. Deposited with reference to the publisher’s open access archiving policy. (http://www.rioxx.net/licenses/all-rights-reserved)|
|Appears in Collections:||Published Articles, Dept. of Physics and Astronomy|
Files in This Item:
|Fletcher_2018_AJ_156_67.pdf||Published (publisher PDF)||3.87 MB||Adobe PDF||View/Open|
Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.