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  1. Artikel ; Online: A rapidly time-varying equatorial jet in Jupiter's deep interior.

    Bloxham, Jeremy / Cao, Hao / Stevenson, David J / Connerney, John E P / Bolton, Scott J

    Nature

    2024  Band 627, Heft 8002, Seite(n) 64–66

    Abstract: Planetary magnetic fields provide a window into the otherwise largely inaccessible dynamics of a planet's deep interior. In particular, interaction between fluid flow in electrically conducting interior regions and the magnetic field there gives rise to ... ...

    Abstract Planetary magnetic fields provide a window into the otherwise largely inaccessible dynamics of a planet's deep interior. In particular, interaction between fluid flow in electrically conducting interior regions and the magnetic field there gives rise to observable secular variation (time dependency) of the externally observed magnetic field. Secular variation of Jupiter's field has recently been revealed
    Sprache Englisch
    Erscheinungsdatum 2024-03-06
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-024-07046-3
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  2. Artikel ; Online: Lightning at Jupiter pulsates with a similar rhythm as in-cloud lightning at Earth.

    Kolmašová, Ivana / Santolík, Ondřej / Imai, Masafumi / Kurth, William S / Hospodarsky, George B / Connerney, John E P / Bolton, Scott J / Lán, Radek

    Nature communications

    2023  Band 14, Heft 1, Seite(n) 2707

    Abstract: Our knowledge about the fine structure of lightning processes at Jupiter was substantially limited by the time resolution of previous measurements. Recent observations of the Juno mission revealed electromagnetic signals of Jovian rapid whistlers at a ... ...

    Abstract Our knowledge about the fine structure of lightning processes at Jupiter was substantially limited by the time resolution of previous measurements. Recent observations of the Juno mission revealed electromagnetic signals of Jovian rapid whistlers at a cadence of a few lightning discharges per second, comparable to observations of return strokes at Earth. The duration of these discharges was below a few milliseconds and below one millisecond in the case of Jovian dispersed pulses, which were also discovered by Juno. However, it was still uncertain if Jovian lightning processes have the fine structure of steps corresponding to phenomena known from thunderstorms at Earth. Here we show results collected by the Juno Waves instrument during 5 years of measurements at 125-microsecond resolution. We identify radio pulses with typical time separations of one millisecond, which suggest step-like extensions of lightning channels and indicate that Jovian lightning initiation processes are similar to the initiation of intracloud lightning at Earth.
    Sprache Englisch
    Erscheinungsdatum 2023-05-23
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-023-38351-6
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Buch ; Online: Strong resemblance between surface and deep zonal winds inside Jupiter revealed by high-degree gravity moments

    Cao, Hao / Bloxham, Jeremy / Park, Ryan S. / Militzer, Burkhard / Yadav, Rakesh K. / Kulowski, Laura / Stevenson, David J. / Bolton, Scott J.

    2023  

    Abstract: Jupiter's atmosphere-interior is a coupled fluid dynamical system strongly influenced by the rapid background rotation. While the visible atmosphere features east-west zonal winds on the order of 100 m/s (Tollefson et al. 2017), zonal flows in the dynamo ...

    Abstract Jupiter's atmosphere-interior is a coupled fluid dynamical system strongly influenced by the rapid background rotation. While the visible atmosphere features east-west zonal winds on the order of 100 m/s (Tollefson et al. 2017), zonal flows in the dynamo region are significantly slower, on the order of 1 cm/s or less, according to the latest magnetic secular variation analysis (Bloxham et al. 2022). The vertical profile of the zonal flows and the underlying mechanism remain elusive. The latest Juno radio tracking measurements afforded the derivation of Jupiter's gravity field to spherical harmonic degree 40. Here, we use the latest gravity solution to reconstruct Jupiter's deep zonal winds without a priori assumptions about their latitudinal profile. The pattern of our reconstructed deep zonal winds strongly resembles that of the surface wind within $\pm$ 35 degrees latitude from the equator, in particular the northern off-equatorial jet (NOEJ) and the southern off-equatorial jet (SOEJ) (Kulowski et al. 2021). The reconstruction features larger uncertainties in the southern hemisphere due to the north south asymmetric nature of Juno's trajectory. Amplitude of the reconstructed deep NOEJ matches that of the surface wind when the wind is truncated at a depth around 2500 km, and becomes twice that of the surface wind if the truncation depth is reduced to about 1500 km. Our analysis supports the physical picture in which prominent part of the surface zonal winds extends into Jupiter's interior significantly deeper than the water cloud layer.

    Comment: Accepted for publication in ApJ, 11 pages, 6 figures
    Schlagwörter Astrophysics - Earth and Planetary Astrophysics ; Physics - Fluid Dynamics
    Thema/Rubrik (Code) 551
    Erscheinungsdatum 2023-11-19
    Erscheinungsland us
    Dokumenttyp Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel ; Online: Juno spacecraft gravity measurements provide evidence for normal modes of Jupiter.

    Durante, Daniele / Guillot, Tristan / Iess, Luciano / Stevenson, David J / Mankovich, Christopher R / Markham, Steve / Galanti, Eli / Kaspi, Yohai / Zannoni, Marco / Gomez Casajus, Luis / Lari, Giacomo / Parisi, Marzia / Buccino, Dustin R / Park, Ryan S / Bolton, Scott J

    Nature communications

    2022  Band 13, Heft 1, Seite(n) 4632

    Abstract: The Juno spacecraft has been collecting data to shed light on the planet's origin and characterize its interior structure. The onboard gravity science experiment based on X-band and Ka-band dual-frequency Doppler tracking precisely measured Jupiter's ... ...

    Abstract The Juno spacecraft has been collecting data to shed light on the planet's origin and characterize its interior structure. The onboard gravity science experiment based on X-band and Ka-band dual-frequency Doppler tracking precisely measured Jupiter's zonal gravitational field. Here, we analyze 22 Juno's gravity passes to investigate the gravity field. Our analysis provides evidence of new gravity field features, which perturb its otherwise axially symmetric structure with a time-variable component. We show that normal modes of the planet could explain the anomalous signatures present in the Doppler data better than other alternative explanations, such as localized density anomalies and non-axisymmetric components of the static gravity field. We explain Juno data by p-modes having an amplitude spectrum with a peak radial velocity of 10-50 cm/s at 900-1200 μHz (compatible with ground-based observations) and provide upper bounds on lower frequency f-modes (radial velocity smaller than 1 cm/s). The new Juno results could open the possibility of exploring the interior structure of the gas giants through measurements of the time-variable gravity or with onboard instrumentation devoted to the observation of normal modes, which could drive spacecraft operations of future missions.
    Sprache Englisch
    Erscheinungsdatum 2022-08-30
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-022-32299-9
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Artikel: Probing Jovian Broadband Kilometric Radio Sources Tied to the Ultraviolet Main Auroral Oval With Juno.

    Imai, Masafumi / Greathouse, Thomas K / Kurth, William S / Gladstone, G Randall / Louis, Corentin K / Zarka, Philippe / Bolton, Scott J / Connerney, John E P

    Geophysical research letters

    2019  Band 46, Heft 2, Seite(n) 571–579

    Abstract: Observations of Jovian broadband kilometric (bKOM) radiation and ultraviolet (UV) auroras were acquired with the Waves and Juno-UVS instruments for ∼2 hr over the northern and southern polar regions during Juno's perijoves 4, 5, and 6 passes (PJ4, PJ5, ... ...

    Abstract Observations of Jovian broadband kilometric (bKOM) radiation and ultraviolet (UV) auroras were acquired with the Waves and Juno-UVS instruments for ∼2 hr over the northern and southern polar regions during Juno's perijoves 4, 5, and 6 passes (PJ4, PJ5, and PJ6). During all six time periods, Juno traversed auroral magnetic field lines connecting to the UV main auroral ovals, matching the estimates of bKOM radio source footprints. The localized bKOM radio sources for the PJ4 north pass map to magnetic field lines having distances of 10 to 12 Jovian radii (R
    Sprache Englisch
    Erscheinungsdatum 2019-01-24
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 7403-2
    ISSN 0094-8276
    ISSN 0094-8276
    DOI 10.1029/2018GL081227
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel: Jupiter's Overturning Circulation: Breaking Waves Take the Place of Solid Boundaries.

    Ingersoll, Andrew P / Atreya, Sushil / Bolton, Scott J / Brueshaber, Shawn / Fletcher, Leigh N / Levin, Steven M / Li, Cheng / Li, Liming / Lunine, Jonathan I / Orton, Glenn S / Waite, Hunter

    Geophysical research letters

    2021  Band 48, Heft 23, Seite(n) e2021GL095756

    Abstract: Cloud-tracked wind observations document the role of eddies in putting momentum into the zonal jets. Chemical tracers, lightning, clouds, and temperature anomalies document the rising and sinking in the belts and zones, but questions remain about what ... ...

    Abstract Cloud-tracked wind observations document the role of eddies in putting momentum into the zonal jets. Chemical tracers, lightning, clouds, and temperature anomalies document the rising and sinking in the belts and zones, but questions remain about what drives the flow between the belts and zones. We suggest an additional role for the eddies, which is to generate waves that propagate both up and down from the cloud layer. When the waves break they deposit momentum and thereby replace the friction forces at solid boundaries that enable overturning circulations on terrestrial planets. By depositing momentum of one sign within the cloud layer and momentum of the opposite sign above and below the clouds, the eddies maintain all components of the circulation, including the stacked, oppositely rotating cells between each belt-zone pair, and the zonal jets themselves.
    Sprache Englisch
    Erscheinungsdatum 2021-10-25
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 7403-2
    ISSN 0094-8276
    ISSN 0094-8276
    DOI 10.1029/2021gl095756
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  7. Buch ; Online: Determining the depth of Jupiter's Great Red Spot with Juno

    Galanti, Eli / Kaspi, Yohai / Simons, Frederik J. / Durante, Daniele / Parisi, Marzia / Bolton, Scott J.

    a Slepian approach

    2019  

    Abstract: One of Jupiter's most prominent atmospheric features, the Great Red Spot (GRS), has been observed for more than two centuries, yet little is known about its structure and dynamics below its observed cloud-level. While its anticyclonic vortex appearance ... ...

    Abstract One of Jupiter's most prominent atmospheric features, the Great Red Spot (GRS), has been observed for more than two centuries, yet little is known about its structure and dynamics below its observed cloud-level. While its anticyclonic vortex appearance suggests it might be a shallow weather-layer feature, the very long time span for which it was observed implies it is likely deeply rooted, otherwise it would have been sheared apart by Jupiter's turbulent atmosphere. Determining the GRS depth will shed light not only on the processes governing the GRS, but on the dynamics of Jupiter's atmosphere as a whole. The Juno mission single flyby over the GRS (PJ7) discovered using microwave radiometer measurements that the GRS is at least a couple hundred kilometers deep (Li et al. 2017). The next flybys over the GRS (PJ18 and PJ21), will allow high-precision gravity measurements that can be used to estimate how deep the GRS winds penetrate below the cloud-level. Here we propose a novel method to determine the depth of the GRS based on the new gravity measurements and a Slepian function approach that enables an effective representation of the wind-induced spatially-confined gravity signal, and an efficient determination of the GRS depth given the limited measurements. We show that with this method the gravity signal of the GRS should be detectable for wind depths deeper than 300 kilometers, with reasonable uncertainties that depend on depth (e.g., $\pm$100km for a GRS depth of 1000km).
    Schlagwörter Astrophysics - Earth and Planetary Astrophysics
    Thema/Rubrik (Code) 551
    Erscheinungsdatum 2019-03-24
    Erscheinungsland us
    Dokumenttyp Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  8. Artikel ; Online: Small lightning flashes from shallow electrical storms on Jupiter.

    Becker, Heidi N / Alexander, James W / Atreya, Sushil K / Bolton, Scott J / Brennan, Martin J / Brown, Shannon T / Guillaume, Alexandre / Guillot, Tristan / Ingersoll, Andrew P / Levin, Steven M / Lunine, Jonathan I / Aglyamov, Yury S / Steffes, Paul G

    Nature

    2020  Band 584, Heft 7819, Seite(n) 55–58

    Abstract: Lightning flashes have been observed by a number of missions that visited or flew by Jupiter over the past several decades. Imagery led to a flash rate estimate of about 4 × ... ...

    Abstract Lightning flashes have been observed by a number of missions that visited or flew by Jupiter over the past several decades. Imagery led to a flash rate estimate of about 4 × 10
    Sprache Englisch
    Erscheinungsdatum 2020-08-05
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-020-2532-1
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  9. Artikel: Magnetotail Reconnection at Jupiter: A Survey of Juno Magnetic Field Observations.

    Vogt, Marissa F / Connerney, John E P / DiBraccio, Gina A / Wilson, Rob J / Thomsen, Michelle F / Ebert, Robert W / Clark, George B / Paranicas, Christopher / Kurth, William S / Allegrini, Frédéric / Valek, Phil W / Bolton, Scott J

    Journal of geophysical research. Space physics

    2020  Band 125, Heft 3

    Abstract: At Jupiter, tail reconnection is thought to be driven by an internal mass loading and release process called the Vasyliunas cycle. Galileo data have shown hundreds of reconnection events occurring in Jupiter's magnetotail. Here we present a survey of ... ...

    Abstract At Jupiter, tail reconnection is thought to be driven by an internal mass loading and release process called the Vasyliunas cycle. Galileo data have shown hundreds of reconnection events occurring in Jupiter's magnetotail. Here we present a survey of reconnection events observed by Juno during its first 16 orbits of Jupiter (July 2016-October 2018). The events are identified using Juno magnetic field data, which facilitates comparison to the Vogt et al. (2010, https://doi.org/10.1029/2009JA015098) survey of reconnection events from Galileo magnetometer data, but we present data from Juno's other particle and fields instruments for context. We searched for field dipolarizations or reversals and found 232 reconnection events in the Juno data, most of which featured an increase in |
    Sprache Englisch
    Erscheinungsdatum 2020-02-27
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 2169-9380
    ISSN 2169-9380
    DOI 10.1029/2019ja027486
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  10. Artikel ; Online: The depth of Jupiter's Great Red Spot constrained by Juno gravity overflights.

    Parisi, Marzia / Kaspi, Yohai / Galanti, Eli / Durante, Daniele / Bolton, Scott J / Levin, Steven M / Buccino, Dustin R / Fletcher, Leigh N / Folkner, William M / Guillot, Tristan / Helled, Ravit / Iess, Luciano / Li, Cheng / Oudrhiri, Kamal / Wong, Michael H

    Science (New York, N.Y.)

    2021  Band 374, Heft 6570, Seite(n) 964–968

    Abstract: Jupiter’s Great Red Spot (GRS) is the largest atmospheric vortex in the Solar System and has been observed for at least two centuries. It has been unclear how deep the vortex extends beneath its visible cloud tops. We examined the gravity signature of ... ...

    Abstract Jupiter’s Great Red Spot (GRS) is the largest atmospheric vortex in the Solar System and has been observed for at least two centuries. It has been unclear how deep the vortex extends beneath its visible cloud tops. We examined the gravity signature of the GRS using data from 12 encounters of the Juno spacecraft with the planet, including two direct overflights of the vortex. Localized density anomalies due to the presence of the GRS caused a shift in the spacecraft line-of-sight velocity. Using two different approaches to infer the GRS depth, which yielded consistent results, we conclude that the GRS is contained within the upper 500 kilometers of Jupiter’s atmosphere.
    Sprache Englisch
    Erscheinungsdatum 2021-10-28
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.abf1396
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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