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A planetary-scale disturbance in the most intense Jovian atmospheric jet from JunoCam and ground-based observations

TL;DR: A huge planetary-scale disturbance in the highest-speed Jovian jet at latitude 235°N was first observed in October 2016 during the Juno perijove-2 approach.
Abstract: We describe a huge planetary-scale disturbance in the highest-speed Jovian jet at latitude 235°N that was first observed in October 2016 during the Juno perijove-2 approach An extraordinary outburst of four plumes was involved in the disturbance development They were located in the range of planetographic latitudes from 222° to 230°N and moved faster than the jet peak with eastward velocities in the range 155 to 175 m s−1 In the wake of the plumes, a turbulent pattern of bright and dark spots (wave number 20–25) formed and progressed during October and November on both sides of the jet, moving with speeds in the range 100–125 m s−1 and leading to a new reddish and homogeneous belt when activity ceased in late November Nonlinear numerical models reproduce the disturbance cloud patterns as a result of the interaction between local sources (the plumes) and the zonal eastward jet

Summary (2 min read)

1. Introduction

  • Planetary-scale disturbances in Jupiter’s atmosphere are the main source of the changes in the belt-zone albedo pattern and in the global appearance of the planet.
  • The authors refer to these great disturbances as the SEBD and the NTBD, following previous works by Sánchez-Lavega et al. [1991, 2008] (see Rogers [2016] for the nomenclature of events at these latitudes).
  • Were active in generating the disturbance, whereas in the last two well-studied events in 1990 and 2007 there were two plumes.

2.1. Pre-outbreak Clouds

  • This suggests that this narrow band was a region depleted in high-altitude aerosols, with UV brightness due to Rayleigh scattering and methane band darkness due to gas absorption.
  • The authors performed a preliminary analysis of photometrically calibrated PlanetCam images obtained before the outbreak on 19 May 2016 using nine filters from the UV (378 nm) to three near-infrared methane absorption bands (M2—727 nm, M3—890 nm, and YM— 1.162 μm) and their adjacent continuums .
  • At 658 nm, the northern and southern parts of the jet, with cyclonic (latitude range 24° to 29°) and anticyclonic (19° to 23.5°) ambient vorticities, respectively, were turbulent and occupied by a pattern of spots at visible wavelengths, darker on the southern side where they showed a wavy appearance with some spatial periodicity .
  • Color composite maps showed that the southern pattern was pale blue but at the jet and on the northern side the color was brown, denoting the effects of altitude differences and probably differences in the nature of chromophores at both sides of the jet (see supporting information).

2.3. The Planetary-Scale Disturbance

  • As observed in previous cases [Sánchez-Lavega et al., 1991, 2008], each plume generated a wake consisting of a turbulent pattern of bright and dark spots that forms continuously on their westward side (i.e., following them) that progressed during October and November at both sides of the jet peak spanning a latitude SÁNCHEZ-LAVEGA ET AL.
  • JUPITER’S NTB JET DISTURBANCE 4681 motions in the bright arc-shaped side (high clouds and reflectivity at 2.16 μm).
  • The equatorward latitude of the reddish belt edge (22.8°) is where the plumes emerged, whereas the northern edge corresponds to a latitude (26.7°) where the measurements of the velocity of the features pertaining to the disturbance show a sudden change in their velocity.
  • In Figure 4 the authors compare the wind profile measured before the eruption and the velocities of the features pertaining to the NTBD.
  • According to the Rayleigh-Kuo criterion, this implies that β d2udy2 changes sign in the domain .

4. Dynamical Numerical Modeling

  • The authors have employed two dynamical models to simulate the observed cloud field and motions of the NTBD: a shallow water (SW) model [Legarreta et al., 2016; García-Melendo and Sánchez-Lavega, 2017] and the Explicit SÁNCHEZ-LAVEGA ET AL.
  • In Figure 5 the authors show selected results of their simulations using both models when injecting three sources (each 1° in radius) placed at longitudes 0°, 40°, and 240°.
  • Out of these latitudes results diverged from the observed morphology.
  • Both the SW and EPIC models require that the sources must be located at 24.5°N.
  • From the dynamical point of view, both models are able to reproduce the general periodic patterns, suggesting that they are generated by the divergence of upwelling material transported aloft by the convective activity close to the tropopause, the injection of relative vorticity, and its interaction with the jet peak at 23.5°.

5. Discussion

  • There are some aspects of the disturbances that are mysterious:.
  • The same analysis of both Juno and Earth-based supporting observations following perijove-3 on 11 December, i.e., when the plumes have ceased and the mixing in the latitude band has formed the reddish belt, will provide information on the perturbations the disturbance has produced.

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A planetary-scale disturbance in the most intense
Jovian atmospheric jet from JunoCam
and ground-based observations
A. Sánchez-Lavega
1
, J. H. Rogers
2
, G. S. Orton
3
, E. García-Melendo
4
, J. Legarreta
5
, F. Colas
6
,
J. L. Dauvergne
7
, R. Hueso
1
, J. F. Rojas
1
, S. Pérez-Hoyos
1
, I. Mendikoa
1
, P. Iñurrigarro
1
,
J. M. Gomez-Forrellad
4
, T. Momary
3
, C. J. Hansen
8
, G. Eichstaedt
9
, P. Miles
10
,
and A. Wesley
11
1
Departamento Física Aplicada I, Escuela de Ingeniería de Bilbao, Universidad del País Vasco UPV/EHU, Bilbao, Spain,
2
British Astronomical Association, London, UK,
3
Jet Propulsion Laboratory, Pasadena, California, USA,
4
Fundació Observatori
Esteve Duran, Seva, Spain,
5
Sistemen Ingeniaritza eta Automatika Saila, Bilboko Ingeniaritza Eskola, Euskal Herriko
Uniberstitatea UPV/EHU, Bilbao, Spain,
6
IMCCE, Observatoire de Paris, Paris, France,
7
S2P, Ciel et Espace, Paris, France,
8
Planetary Science Institute, Tucson, Arizona, USA,
9
Independent Scholar, Stuttgart, Germany,
10
Gemeye Observatory,
Rubyvale, Queensland, Australia,
11
Astronomical Society of Australia, Murrumbateman, New South Wales, Australia
Abstract We describe a huge planetary-scale disturbance in the highest-speed Jovian jet at latitude
23.5°N that was rst observed in October 2016 during the Juno perijove-2 approach. An extraordinary
outburst of four plumes was involved in the disturbance development. They were located in the range of
planetographic latitudes from 22.2° to 23.0°N and moved faster than the jet peak with eastward velocities in
the range 155 to 175 m s
1
. In the wake of the plumes, a turbulent pattern of bright and dark spots (wave
number 2025) formed and progressed during October and November on both sides of the jet, moving with
speeds in the range 100125 m s
1
and leading to a new reddish and homogeneous belt when activity
ceased in late November. Nonlinear numerical models reproduce the disturbance cloud patterns as a result of
the interaction between local sources (the plumes) and the zonal eastward jet.
1. Introduction
Planetary-scale disturbances in Jupiters atmosphere are the main source of the changes in the belt-zone
albedo pattern and in the global appearance of the planet. There are two regions of Jupiter, the South
Equatorial Belt (SEB) at planetographic latitude ~16°S and the North Temperate Belt southern component
(NTBs) at latitude 23.5°N, that undergo such changes in a dramatic and somewhat similar manner [Peek,
1958; Rogers, 1995; Sánchez-Lavega and Gómez, 1996; Sánchez-Lavega et al., 2008]. They start from a similar
single or multiple convective outbreak that manifests as a bright spot (at visual wavelengths) whose interac-
tion with the sheared background winds forms a characteristic disturbance that propagates relative to the
outbreak source, encircling the whole latitude in ~13 months, nally generating a new low-albedo band
(a belt). We refer to these great disturbances as the SEBD and the NTBD, following previous works by
Sánchez-Lavega et al. [1991, 2008] (see Rogers [2016] for the nomenclature of events at these latitudes).
Just like the similar Great White Spot phenomena in Saturn s atmosphere [Sánchez-Lavega et al., 2017], these
outbreak events give us information on the atmospheric dynamics and cloud and aerosol behavior over the
pressure range in altitude from 0.01 to 5 bar.
A typical NTBD (plume outbreak and planetary-scale disturbance) starts at the latitude ~23.5°N on the peak of
the most rapid Jovian jet at cloud tops (pressure level ~0.7 bar) as observed at visual wavelengths [Rogers,
1995; Sánchez-Lavega et al., 2008]. The jet peak velocity ranges from ~135 to 175 m s
1
, where this variability
could be intrinsic or related to different altitudes of the tracers coupled to a possible vertical wind shear.
The jet gradually accelerates before a NTBD outbreak, until it reaches almost the speed of the subsequent
plumes [Rogers et al., 2006; Sanchez-Lavega et al., 2008]. The best studied events occurred in 1975 [Rogers,
1976; Sánchez-Lavega and Quesada, 1988], 1990 [Sánchez-Lavega, et al., 1991; Rogers, 1992; García-Melendo
et al., 2005], and 2007 [Sánchez-Lavega et al., 2008; Rogers and Mettig, 2008]. The last NTBD before the
present one occurred in April 2012 but was not well observed due to solar conjunction [Rogers and
Adamoli, 2012]. Here we present a study of the 2016 outbreak that was exceptional since four plumes
SÁNCHEZ-LAVEGA ET AL. JUPITERS NTB JET DISTURBANCE 4679
PUBLICATION
S
Geophysical Research Letters
RESEARCH LETTER
10.1002/2017GL073421
Special Section:
Early Results: Juno at Jupiter
Key Points:
A planetary-scale disturbance
developed in the highest-speed
Jupiter jet at 23.5°N latitude during
October and November 2016
Four plumes were involved in the
outbreak moving with speeds
between 155 and 175 m s
1
, the
fastest features at cloud level
Nonlinear numerical models
reproduce the disturbance from the
interaction between local sources (the
plumes) and the zonal eastward jet
Supporting Information:
Supporting Information S1
Correspondence to:
A. Sánchez-Lavega,
agustin.sanchez@ehu.eus
Citation:
Sánchez-Lavega, A., et al. (2017), A
planetary-scale disturbance in the most
intense Jovian atmospheric jet from
JunoCam and ground-based
observations, Geophys. Res. Lett., 44,
46794686, doi:10.1002/2017GL073421.
Received 18 MAR 2017
Accepted 12 APR 2017
Published online 25 MAY 2017
©2017. American Geophysical Union.
All Rights Reserved.

were active in generating the disturbance, whereas in the last two well-studied events in 1990 and 2007
there were two plumes. In addition, this eruption took place shortly before the Juno spacecraft perijove-
2 (PJ2) on 19 October.
2. Observations
For this study we used the following: (1) images obtained in the spectral range 0.381 μm with telescopes of
2550 cm in diameter, from the Planetary Virtual Observatory and Laboratory (PVOL) database [Hueso et al.,
2010, 2017a] and with telescopes from the Aula EspaZio Gela Observatory [Sánchez-Lavega et al., 2014]; (2)
images obtained with PlanetCam lucky imaging camera that operates between 0.38 and 1.7 μm mounted
on the 2.2 m telescope at Calar Alto Observatory in Spain [Mendikoa et al., 2016]; (3) JunoCam color image
series [ Hansen et al., 2014] obtained during perijove-2 approach between 11 and 14 October; (4) the 3 m
planetary-dedicated NASA Infrared Telescope Facility (IRTF) using the SpeX imager (wavelengths 1.58, 1.64,
1.65, 2.16, 2.26, 3.42, 3.8, and 5.1 μm); and (5) the 1 m planetary-dedicated telescope at Pic-du-Midi
Observatory (France) in the red range (0.6 1 μ m). See supporting information for the list of contributors, data-
bases, and methods used to analyze these images.
2.1. Pre-outbreak Clouds
Hubble Space Telescope (HST) maps of the cloud morphology obtained on 910 February 2016 show that
northward of the jet peak in a conspicuous narrow band from latitudes 24.5° ± 0.2° to 25.5° ± 0.4°, the
reectivity at 275 nm was high relative to surroundings, but it was low in the 890 nm methane absorption
band (OPAL program [Simon et al., 2015] (Figures S1 and S5 [Hueso et al., 2017b]). This suggests that this
narrow band was a region depleted in high-altitude aerosols, with UV brightness due to Rayleigh scattering
and methane band darkness due to gas absorption. We performed a preliminary analysis of photometrically
calibrated PlanetCam images obtained before the outbreak on 19 May 2016 using nine lters from the UV
(378 nm) to three near-infrared methane absorption bands (M2727 nm, M3890 nm, and YM
1.162 μm) and their adjacent continuums (Figure S2). Radiative transfer models for February 2016 show a
particle-free stratosphere and upper troposphere with a haze deck located at 370 ± 100 mbar with optical
thickness of τ
haze
= 3.8 ± 0.6, above a cloud (τ
cloud
= 6.0 ± 2.0) assumed to be located at the ammonia
condensation level (~ 700 mbar) (see supporting information).
At 658 nm, the northern and southern parts of the jet, with cyclonic (latitude range 24° to 29°) and anticyclo-
nic (19° to 23.5°) ambient vorticities, respectively, were turbulent and occupied by a pattern of spots at visible
wavelengths, darker on the southern side where they showed a wavy appearance with some spatial periodi-
city (Figure S1). Color composite maps showed that the southern pattern was pale blue but at the jet and on
the northern side the color was brown, denoting the effects of altitude differences and probably differences
in the nature of chromophores at both sides of the jet (see supporting information).
2.2. Disturbance Outbreak: The Plumes
JunoCam images obtained between 11 and 14 October during the PJ2 approach phase (PJ2 was on 19
October) showed, at high phase angle and low resolution, bright and dark spots pertaining to the NTBs jet
outbreak [Rogers, 2016] (Figure 1a). Four bright spots or plumes labeled as A, B, C, and D were sequentially
captured as they came into view as the planet rotated (in section 2.3 we give estimates of the outbreak times).
Their mutual separation ranged from ~27,000 km to 229,500 km (Figures 1b and 2). The brightest part of the
plumes A and D (their cores) had a size of 4700 km (east-west) and 3200 km (north-south), as measured on
19 October at 3.8 μm from IRTF images. The plumes were bright at 2.12 and 2.16 μm where molecular hydro-
gen absorption dominates and at 3.8 μm that senses altitude levels above the main upper cloud layer [Irwin,
2003]. However, they do not appear at 5.1 μm (Figure S3), sensitive to thermal infrared radiation from the
interior, indicating that they had high opacity, consistent with the presence of thick clouds. Both aspects
are in good agreement with the high cloud-altitude and high-opacity plumes quantitatively described in
Sánchez-Lavega et al. [2008].
The plumes emerged in the anticyclonic southern ank of the undisturbed jet (Figure 3). Plume A was located
at latitude +22.4° ± 0.7° and had a longitude drift rate of 4.2°/d in System I (SI) (speed 157.3 ± 1.1 m s
1
in
System III or SIII) as retrieved from a simple linear t (Figure 2). Throughout the paper, the velocities given in
ms
1
take System III as reference (see supporting information for system denitions). Plume D was at
Geophysical Research Letters
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SÁNCHEZ-LAVEGA ET AL. JUPITERS NTB JET DISTURBANCE 4680

+23.0° ± 1.0° and had a drift rate of 5.64°/d in SI (speed 176.4 ± 1.3 m s
1
). Plumes B and C showed a more
complex behavior. The drift rate of these plumes suggests that a merger of B and C could have occurred, but
it is also possible that one of them disappeared rapidly. Two motion solutions are possible, one extremely fast
with drift rate 7.2°/d in SI (198.6 ± 2 m s
1
) never observed on Jupiter and the other with 4.8°/d in SI
(166.5 ± 1.8 m s
1
) for the track of B plus C after 19 October (latitude +22.2° ± 0.8°). We adopt this second
case for our wind prole and simulations, calling this plume C. Plumes C and D disappeared by the end of
October upon arriving at the location of the chains of dark spots preceding them and located to the north
of the jet (Figures 3 and 4), but A was alive until early November. The lifetimes of the plumes of about
1 month are typical of the NTBD phenomena [Sánchez-Lavega et al., 1991, 2008].
2.3. The Planetary-Scale Disturbance
As observed in previous cases [Sánchez-Lavega et al., 1991, 2008], each plume generated a wake consisting of
a turbulent pattern of bright and dark spots that forms continuously on their westward side (i.e., following
them) that progressed during October and November at both sides of the jet peak spanning a latitude
Figure 1. Images of the NTBD outbreak plumes: (a) JunoCam image series obtained on 14 October in SCET (UT at spacecraft, hh:mm:ss), from right to left: Image 085
(09:43:31), Image 089 (10:45:07), Image 091 (11:15:10), Image 113 (16:45:16), and Image 115 (17:15:20). The dark spots pertaining to the NTBD (blue arrows) and the
four different plumes (A, B, C, and D) are marked by red arrows and circles, respectively. (b) SpeX IRTF images on 19 October showing plumes (A, C, and D) at wavelengths
3.8 μm (19:47:39 UT, left, and 17:50:27 UT, middle) and 2.12 μm (19:56:51, right). (c) Map showing the location of plumes C, A, and D from the series (Figure 1b).
Geophysical Research Letters
10.1002/2017GL073421
SÁNCHEZ-LAVEGA ET AL. JUPITERS NTB JET DISTURBANCE 4681

band from ~19° to 27°N (Figure 3) and
being nearly stationary relative to
System I (Figure 2). Pre-outbreak images
from July and August 2016 show the
NTB free of this pattern (images avail-
able on PVOL server; see supporting
information). The turbulent pattern was
formed by a chain of alternating irregu-
lar dark and bright features as observed
at red continuum wavelengths, with an
approximate wave number of 2025
(wavelengths ~8000 10,000 km). The
highest-resolution images (31 October
to 6 November) showed the pattern of
dark spots at latitude 24.5° ± 0.5°N in
the cyclonic side of the pre-outbreak
jet prole and bright arc-shaped la-
ments at 21.5° ± 0.5° in the pre-outbreak
anticyclonic side (Figure 3). Each dark
bright feature had a length of
~14,000 km, and its morphology, reec-
tivity in the visual, and radiance at short
infrared wavelengths (1.58, 2.16, 3.8, and
5.1 μm, Figures 3 and S4) were consis-
tent with descending motions in the
cyclonic side (low cloud opacity and
high radiances at 5.1 μm) and ascending
motions in the bright arc-shaped side (high clouds and reectivity at 2.16 μm). The mean speed of these fea-
tures was nearly constant from ~21 to 26°N (Figure 4), and they formed a pattern reminiscent of the NEBs dark
formations (hot spots), gyres, and EZn festoons, so they could be wave-induced features, as our numerical
modeling suggests (see section 4). Tracking these features yielded speeds in the range 100125 m s
1
relative
to System III or ~ 50 m s
1
relative to NTBs pre-outbreak jet peak speeds (Figures 2 and 3).
The rst images of the plumes on 1113 October by JunoCam showed that the long chain of dark spots west-
ward of plumes B and C extended ~120° in longitude or 159,000 km. Assuming a relative speed of ~60 m s
1
between the plumes and the dark spot pattern, the outbreak of B or C or both probably occurred around
1316 September. Similarly, on 19 October the disturbance pattern westward of plume D extended ~65°
or 75,000 km indicating that its outbreak probably occurred on 48 October. The separation between plume
D and the others was too large for one to have triggered the others, suggesting that an unknown process at a
deeper level triggered multiple outbreaks within a short time span, as has been observed at previous out-
breaks [Sánchez-Lavega et al., 1991, 2008].
Once the plumes ceased their activity, the mixing of the features forming the disturbance, most probably
generated by turbulence and wind shear, began to form a new North Temperate Belt. At the end of
November a red and uniform belt was visible over the jet spanning a latitude range from 22.8° to 26.7°,
but all was gray and turbulent on the poleward side from latitudes 26.7° to 32° (Figure S5). The equatorward
latitude of the reddish belt edge (22.8°) is where the plumes emerged, whereas the northern edge corre-
sponds to a latitude (26.7°) where the measurements of the velocity of the features pertaining to the distur-
bance (Figure 4) show a sudden change in their velocity. The white North Tropical Zone showed a long chain
of narrow dark laments tilted from latitudes 19.3° to 22.3° according to the ambient anticyclonic wind shear.
3. Disturbance Motions and Wind Prole
Jupiters wind prole at the upper cloud level was measured in 2016 before the outbreak, using cloud auto-
matic tracking on a large set of images and HST image pairs from February 2016 and also using ground-based
Figure 2. Drift rate in System I longitude of the features pertaining to the
NTBD, tracked between 10 October and 4 November 2016. The plumes A,
C, and D are identied by red dots. Plume B is the blue dot: it disappeared
or merged with plume C. The dark dots indicate features forming the
NTBD westward of the plumes. The lines identify the tracking of the
features. Data from JunoCam images are for 1114 October.
Geophysical Research Letters
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SÁNCHEZ-LAVEGA ET AL. JUPITERS NTB JET DISTURBANCE 4682

Figure 3. Images showing the features pertaining to the NTBD westward of the plumes: (a) Images acquired at the Pic-
du-Midi Observatory obtained within the spectral range 0.7421.0 μm showing the same region of the NTBD after 49 h,
at the indicated days and times. (b) Strips maps of the NTBD on 2 November at the indicated times and wavelengths with
longitude in System I and planetographic latitudes. Two families of features are shown, one at mean planetographic
latitude 24.5° (identied by yellow arrows, cyclonic) and the other at 21.5° (identied by blue dashed arrows, anticyclonic).
However, we note that some of the features in the 2.16 and 3.8 μm images may be unrelated to the NTBD. The red arrow
identies a particularly bright spot, probably transient, at 3.8 μm (high aerosol density). The residual of plume A is probably
the weakly bright spot in the IR 742 nm lter at ~320° I (not present at other wavelengths). (c) Color enlargement showing
the morphology of the rst strip shown in Figure 3b. The cartoon shows a possible circulation for each dark spotarc-
shaped pair within the pre-outbreak meridionally sheared ow at right. The dashed violet line marks the location of the jet
peak before the outbreak.
Geophysical Research Letters
10.1002/2017GL073421
SÁNCHEZ-LAVEGA ET AL. JUPITERS NTB JET DISTURBANCE 4683

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Additional excerpts

  • ...JUPITER’S NTB JET DISTURBANCE 4684 Planetary Isentropic-Coordinate (EPIC) general circulation model [Dowling et al., 1998; García-Melendo et al., 2005]; see supporting information for details and Sánchez-Lavega [2011] for definitions....

    [...]

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24 Jan 2008-Nature
TL;DR: Observations and modelling of two plumes in Jupiter's atmosphere that erupted at the same latitude as the strongest jet and left in their wake a turbulent planetary-scale disturbance containing red aerosols conclude that the data are consistent only with a wind that extends well below the level where solar radiation is deposited.
Abstract: To coincide with the flyby of the Pluto-bound New Horizons probe, Jupiter was the target of intensive observation, starting in February 2007, from a battery of ground-based telescopes and the Hubble Space Telescope (HST). Weeks into the project, on 25 March, an intense disturbance developed in Jupiter's strongest jet at 23° North latitude, lasting to June 2007. This type of event is rare — the last ones were seen in 1990 and 1975. The onset of the disturbance was captured by the HST, and the development of two plumes was followed in unprecedented detail. The two plumes (bright white spots in the small infrared image on the cover) towered 30 km above the surrounding clouds. The nature of the power source for the jets that dominate the atmospheres of Jupiter and Saturn is a controversial matter, complicated by the interplay of local and planet-wide meteorological factors. The new observations are consistent with a wind extending deep into the atmosphere, well below the level reached by solar radiation. In the larger cover image, turbulence caused by the plumes can be seen in the band that is home to the jet. Observations and modelling of two plumes in Jupiter's atmosphere that erupted at the same latitude as the strongest jet (23° North) are reported. Based on dynamical modelling it is concluded that the data are consistent only with a wind that extends well below the level where solar radiation is deposited. The atmospheres of the gas giant planets (Jupiter and Saturn) contain jets that dominate the circulation at visible levels1,2. The power source for these jets (solar radiation, internal heat, or both) and their vertical structure below the upper cloud are major open questions in the atmospheric circulation and meteorology of giant planets1,2,3. Several observations1 and in situ measurements4 found intense winds at a depth of 24 bar, and have been interpreted as supporting an internal heat source. This issue remains controversial5, in part because of effects from the local meteorology6. Here we report observations and modelling of two plumes in Jupiter’s atmosphere that erupted at the same latitude as the strongest jet (23° N). The plumes reached a height of 30 km above the surrounding clouds, moved faster than any other feature (169 m s-1), and left in their wake a turbulent planetary-scale disturbance containing red aerosols. On the basis of dynamical modelling, we conclude that the data are consistent only with a wind that extends well below the level where solar radiation is deposited.

111 citations

Journal ArticleDOI
TL;DR: The first year of the Hubble 2020: Outer Planet Atmospheres Legacy program is generating new yearly global maps for each of the outer planets as mentioned in this paper, focusing on Jupiter results from the first year.
Abstract: The Hubble 2020: Outer Planet Atmospheres Legacy program is generating new yearly global maps for each of the outer planets. This report focuses on Jupiter results from the first year of the campaign. The zonal wind profile was measured and is in the same family as the Voyager and Cassini era profiles, showing some variation in mid- to high-latitude wind jet magnitudes, particularly at +40° and −35° planetographic latitude. The Great Red Spot continues to maintain an intense orange coloration, but also shows new internal structures, including a reduced core and new filamentary features. Finally, a wave that was not previously seen in Hubble images was also observed and is interpreted as a baroclinic instability with associated cyclone formation near 16° N latitude. A similar feature was observed faintly in Voyager 2 images, and is consistent with the Hubble feature in location and scale.

85 citations

Journal ArticleDOI
01 Oct 2009-Icarus
TL;DR: In this second part of the study of the large jovian anticyclone BA, Simon-Miller et al. as discussed by the authors presented detailed measurements of its internal circulation and numerical models of its interaction with the zonal jets and nearby cyclonic regions.

60 citations

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Q1. What are the contributions in "A planetary-scale disturbance in the most intense jovian atmospheric jet from junocam and ground-based observations" ?

The authors describe a huge planetary-scale disturbance in the highest-speed Jovian jet at latitude 23.