Summary Report

Watch the animation in PDF version →Click on: NTrZ ADS#5January 25 – February 15, 2024
NTrZNEBEZMapping: S. Mizumoto

Shinji Mizumoto (ALPO-Japan)

Longitude: L3
Ver.9-2024/05/31

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ALPO-Japan Summary Report2023-24 / Mid-NEB Plume & NTrZ ADSs
［Contents］➢ Cover slide: ADS#5 / Maps Animation

2-3 Plume & ADS#1 / Maps Animation➢ Guidance (Notes)

2-4 Drift Chart & Drift Rate

1. Observation Results

2-5 Latitude Chart

1-1 Plume Eruption & NTrZ ADS#1 Formation

2-6 Longitude-Latitude Chart1-2 ADS#1 Changed to White Spot

2-7 Relationship between Plume, Rift & NEBExpansion

1-3 ADS#5 Formation
1-4 Plume & Five times ADS Formation

2. Analysis
2-1 Plume & ADSs / Juno PJ55-60 Maps
2-2 Plume & ADSs / IRTF 5.1 μm Maps

3. Results
3-1 Results Table
3-2 Results

4. Acknowledgements & References➢ Final slide: ADS#5 / Maps Animation

Guidance (Notes)

3Wind Velocity (eastward m/sec: Vs. L3)

NTrZ

NTrZ ADS#1 ▼NTrZNEB

Mid-NEB plume ▲NEBEZEZSEBSEB

Mapping: S. Mizumoto⚫ Drift Rate (DL3) :± deg/d, ± deg/30d＋: longitude increase－: longitude decrease⚫ Plume: White cloud eruption phenomenon.
⚫ Rift/Rift Activity: Ruptures created by whiteclouds being stretched east-west and north-Lat (deg)[2023/10/13 map: obs. by S. Ito]

[OPAL 2016 Zonal Winds]south by wind velocity gradients in the relevant
latitude region, and such activity.

⚫ (NTrZ) ADS: Anticyclonic Dark Spot
⚫ NEB Expansion/NEB Revival/NEB Outbreak: In
the past, they occurred at 3-5 year intervals.

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Plume Eruption & NTrZ ADS#1 Formation<Plume Eruption>⚫ October 8, 2023: Mid-NEB
plume erupted on p-side of
WS-Z (obs. by I. Miyazaki).
L3=250 deg, L2=219 deg⚫ The plume was a progressive
and intermittent eruption ofwhite clouds, which persisted
for 180 days until the end of
the apparition.
DL3=-1.62 deg/day<ADS#1 Formation>⚫ October 12, 2023: White
clouds supplied by the plumereached the NTrZ through rift
activity, forming the ringshaped NTrZ ADS#1
Mapping: S. Mizumoto(obs. by K. Suzuki, F. Reali).
L3=246 deg, L2=214 deg

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ADS#1 Changed to White Spot

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⚫ Late October 2023: ADS#1
weakened.
⚫ Early November 2023: TheADS became surrounded by awhite cloud, fed by the plume.

January⚫ Late January 2024: The dark
spot gradually faded and had
disappeared, apparently
changing to only white spot.
⚫ Similar phenomena were also
observed with ADS#3.
Mapping: S. Mizumoto

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ADS#5 Formation

6⚫ January 22, 2024: ADS#5
was formed (obs. by A. Wesley).
L3=70 deg, L2=11 deg⚫ Initially, it showed a rapidchange in latitude, reachingnearly +20 degrees, but
about one month after its
formation, it settled at around+18 to +19 degrees (Seeslide 12).

Mapping: S. Mizumoto⚫ Among the five ADSs formed,
it was the largest and its
existence was confirmed overa period of 82 days until theend of the apparition.

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NTrZ

Plume & Five times ADS Formation▼#5▼#1NEB7▲

Mapping: S. Mizumoto▲EZ2023/10/13 S. Ito2024/01/27 S. Ito▼#6▼#2▲▲2023/11/30 C. Go, T.Olivetti▼#3▲2023/12/15 I. Miyazaki

2024/03/15 A. Frantzis⚫ The progressing plume intermittently erupted.
⚫ White clouds supplied by the plume formed
the ADS five times due to rift activity.
⚫ All five ADSs were formed from the same
plume.

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Plume & ADSs / Juno PJ55-60 Maps

Credit: NASA / JPL / SwRI / MSSS / Gerald Eichstädt / John Rogers / Shinji Mizumoto

ADS: Anticyclonic Dark Spot

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Plume & ADSs / IRTF 5.1 μm Maps

Credit: Gordon Bijöraker (NASA/GSFC) / Shinji Mizumoto (ALPO-J)

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IRTF: Infrared Telescope Facility

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Plume & ADS#1 / Maps Animation10｜: Plume↓: NTrZ ADS#1NEB
EZOctober 8 - December 30, 2023

Mapping: S. Mizumoto

Longitude: L3

2-4Drift Chart & Drift Rate

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⚫ NTrZ white spots may be derived from NTrZADSs.
⚫ Early March 2024: Plume decelerated.
⚫ #4 was not an ADS and was not thought tohave a direct relationship with plume-rift
activity.

2-5Latitude Chart

12⚫ The plume has been shifted northsince the end of February 2024.
⚫ ADS#1, ADS#5, (ADS#6):• Initially showed rapid changes
in latitude, reaching up tonearly +20 degrees.
• About one month after theirformation, they settled atlatitudes of +18 to +19degrees.
⚫ ADS#2, ADS#3:• Similar trend were observed,
but they were minor.

⚫ The above latitude changes are
consistent with the longitudechanges (drift chart).

Longitude-Latitude Chart13

N[OPAL 2016 Zonal Winds]
Wind Velocity (eastward m/sec: Vs.L3)#1: Initially showed rapidchanges in latitude#5: Initially showed
rapid changes inlatitude

SDeceleration

N Acceleration
NNTrZDeceleration

NEBEZ

Latitude (deg) → N

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Relationship between Plume, Rift & NEB Expansion

#1▲

#2▲

#1▲

#2▲

#1▲

#1▲

#6▲

#3▲

#2▲

#2▲

#5▲

#5▲

Mapping: S. Mizumoto⚫ Increased activity in the NEBn-NTrZ on the following side of the plume was observed after its
passage, as indicated by pronounced unevenness along the northern edge of the NEB.
⚫ As the NEB's northern edge extended northward and thickened, it also expanded longitudinally,
contributing to the overall NEB expansion.

143-1Results Table15

3-2Results⚫ Mid-NEB plume eruption•

The Mid-NEB plume erupted on October 8, 2023.

•The plume was a progressive and intermittent eruption of white clouds.

•White clouds emerging from the plume were stretched in east-west and north-south directions bywind velocity gradients, forming a rift.

•This phenomenon continued for nearly six months until the end of the apparition.

⚫ NTrZ ADSs formation•

Rift activities led to the transport of white clouds into the NTrZ, where they formed five ring-shapedADSs.

•ADS#1 and ADS#5 initially exhibited rapid shifts in latitude, reaching up to nearly +20 degrees
before stabilizing at latitudes between +18 and +19 degrees one month after formation.

•ADS#1 and ADS#3 eventually transformed into white spots.

⚫ NEB expansion event•Following the plume's passage, the region between the NEB and NTrZ became notably active andunstable.

•The northern edge of the NEB extended and thickened northward.

•As the plume progressed, the expansion of the NEB extended in the direction of decreasinglongitude.

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4 Acknowledgements & ReferencesAcknowledgements⚫ I would like to express my gratitude to all the observers who provided their valuable observation data.
⚫ I would like to express my gratitude to Gordon Bijöraker (NASA/GSFC) for providing the IRTF 5.1 microns
images.
⚫ A special thanks to John H. Rogers (BAA Jupiter Section) for his invaluable input into the preparation ofthis report.

References (Links)
1. Yuichi Iga (2001), Formation of NEB Rift in 2000-2001, ALPO-Japan
2. Yuichi Iga (2002), The Activity of NEB in 2001-2002, ALPO-Japan
3. Kuniaki Horikawa, Chronicle of the Planet Jupiter since 2000, OAA Jupiter-Saturn Section
4. John Rogers (2015), Relationship of NEB rifts to NEB expansion events, BAA Jupiter Section
5. John H. Rogers (2017), Jupiter’s North Equatorial Belt and Jet: I. Cyclic expansions and planetary waves,BAA Jupiter Section
6. John Rogers, Shinji Mizumoto et al. (2022), The transformation of Jupiter’s North Equatorial Belt in
2021-22, EPSC Abstracts
7. John Rogers (2024), Jupiter in 2023/24: Report no.4, BAA Jupiter Section
8. Shinji Mizumoto (2024), 2023-24 NEB Plume and ADSs L3 maps, ALPO-Japan17

18: NTrZ ADS#5

January 25 – February 15, 2024
NTrZNEBEZEnd
Mapping: S. Mizumoto

Shinji Mizumoto (ALPO-Japan)

Longitude: L3