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Wong MH, Rowe-Gurney N, Markham S, Sayanagi KM. Multiple Probe Measurements at Uranus Motivated by Spatial Variability. SPACE SCIENCE REVIEWS 2024; 220:15. [PMID: 38343766 PMCID: PMC10858001 DOI: 10.1007/s11214-024-01050-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 01/18/2024] [Indexed: 02/22/2024]
Abstract
A major motivation for multiple atmospheric probe measurements at Uranus is the understanding of dynamic processes that create and maintain spatial variation in thermal structure, composition, and horizontal winds. But origin questions-regarding the planet's formation and evolution, and conditions in the protoplanetary disk-are also major science drivers for multiprobe exploration. Spatial variation in thermal structure reveals how the atmosphere transports heat from the interior, and measuring compositional variability in the atmosphere is key to ultimately gaining an understanding of the bulk abundances of several heavy elements. We review the current knowledge of spatial variability in Uranus' atmosphere, and we outline how multiple probe exploration would advance our understanding of this variability. The other giant planets are discussed, both to connect multiprobe exploration of those atmospheres to open questions at Uranus, and to demonstrate how multiprobe exploration of Uranus itself is motivated by lessons learned about the spatial variation at Jupiter, Saturn, and Neptune. We outline the measurements of highest value from miniature secondary probes (which would complement more detailed investigation by a larger flagship probe), and present the path toward overcoming current challenges and uncertainties in areas including mission design, cost, trajectory, instrument maturity, power, and timeline.
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Affiliation(s)
- Michael H. Wong
- Center for Integrative Planetary Science, University of California, Berkeley, CA 94720-3411 USA
- Carl Sagan Center for Science, SETI Institute, Mountain View, CA 94043-5232 USA
| | - Naomi Rowe-Gurney
- NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA
- University of Maryland, College Park, MD 20742 USA
- The Center for Research and Exploration in Space Science & Technology (CRESST II), Greenbelt, MD 20771 USA
- The Royal Astronomical Society, Piccadilly, London, W1J 0BD UK
| | - Stephen Markham
- Observatoire de la Côte d’Azur, 06300 Nice, France
- Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 USA
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Ingersoll AP, Adumitroaie V, Allison MD, Atreya S, Bellotti AA, Bolton SJ, Brown ST, Gulkis S, Janssen MA, Levin SM, Li C, Li L, Lunine JI, Orton GS, Oyafuso FA, Steffes PG. Implications of the ammonia distribution on Jupiter from 1 to 100 bars as measured by the Juno microwave radiometer. GEOPHYSICAL RESEARCH LETTERS 2017; 44:7676-7685. [PMID: 33100420 PMCID: PMC7580824 DOI: 10.1002/2017gl074277] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The latitude-altitude map of ammonia mixing ratio shows an ammonia-rich zone at 0-5°N, with mixing ratios of 320-340 ppm, extending from 40-60 bars up to the ammonia cloud base at 0.7 bars. Ammonia-poor air occupies a belt from 5-20°N. We argue that downdrafts as well as updrafts are needed in the 0-5°N zone to balance the upward ammonia flux. Outside the 0-20°N region, the belt-zone signature is weaker. At latitudes out to ±40°, there is an ammonia-rich layer from cloud base down to 2 bars which we argue is caused by falling precipitation. Below, there is an ammonia-poor layer with a minimum at 6 bars. Unanswered questions include how the ammonia-poor layer is maintained, why the belt-zone structure is barely evident in the ammonia distribution outside 0-20°N, and how the internal heat is transported through the ammonia-poor layer to the ammonia cloud base.
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Affiliation(s)
- Andrew P Ingersoll
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - Virgil Adumitroaie
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | | | - Sushil Atreya
- Climate and Space Sciences, University of Michigan, Ann Arbor, MI 48109, USA
| | - Amadeo A Bellotti
- Center for Space Technology and Research, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Scott J Bolton
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - Shannon T Brown
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Samuel Gulkis
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Michael A Janssen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Steven M Levin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Cheng Li
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Liming Li
- Department of Physics, University of Houston, Houston, TX 77004, USA
| | | | - Glenn S Orton
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Fabiano A Oyafuso
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Paul G Steffes
- Center for Space Technology and Research, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Ingersoll AP, Adumitroaie V, Allison MD, Atreya S, Bellotti AA, Bolton SJ, Brown ST, Gulkis S, Janssen MA, Levin SM, Li C, Li L, Lunine JI, Orton GS, Oyafuso FA, Steffes PG. Implications of the ammonia distribution on Jupiter from 1 to 100 bars as measured by the Juno microwave radiometer. GEOPHYSICAL RESEARCH LETTERS 2017; 44:7676-7685. [PMID: 33100420 DOI: 10.1002/2017gl073159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The latitude-altitude map of ammonia mixing ratio shows an ammonia-rich zone at 0-5°N, with mixing ratios of 320-340 ppm, extending from 40-60 bars up to the ammonia cloud base at 0.7 bars. Ammonia-poor air occupies a belt from 5-20°N. We argue that downdrafts as well as updrafts are needed in the 0-5°N zone to balance the upward ammonia flux. Outside the 0-20°N region, the belt-zone signature is weaker. At latitudes out to ±40°, there is an ammonia-rich layer from cloud base down to 2 bars which we argue is caused by falling precipitation. Below, there is an ammonia-poor layer with a minimum at 6 bars. Unanswered questions include how the ammonia-poor layer is maintained, why the belt-zone structure is barely evident in the ammonia distribution outside 0-20°N, and how the internal heat is transported through the ammonia-poor layer to the ammonia cloud base.
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Affiliation(s)
- Andrew P Ingersoll
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - Virgil Adumitroaie
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | | | - Sushil Atreya
- Climate and Space Sciences, University of Michigan, Ann Arbor, MI 48109, USA
| | - Amadeo A Bellotti
- Center for Space Technology and Research, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Scott J Bolton
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - Shannon T Brown
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Samuel Gulkis
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Michael A Janssen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Steven M Levin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Cheng Li
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Liming Li
- Department of Physics, University of Houston, Houston, TX 77004, USA
| | | | - Glenn S Orton
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Fabiano A Oyafuso
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Paul G Steffes
- Center for Space Technology and Research, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Moses JI, Visscher C, Keane TC, Sperier A. On the abundance of non-cometary HCN on Jupiter. Faraday Discuss 2011; 147:103-36; discussion 251-82. [PMID: 21302544 DOI: 10.1039/c003954c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using one-dimensional thermochemical/photochemical kinetics and transport models, we examine the chemistry of nitrogen-bearing species in the Jovian troposphere in an attempt to explain the low observational upper limit for HCN. We track the dominant mechanisms for interconversion of N2-NH3 and HCN-NH3 in the deep, high-temperature troposphere and predict the rate-limiting step for the quenching of HCN at cooler tropospheric altitudes. Consistent with some other investigations that were based solely on time-scale arguments, our models suggest that transport-induced quenching of thermochemically derived HCN leads to very small predicted mole fractions of hydrogen cyanide in Jupiter's upper troposphere. By the same token, photochemical production of HCN is ineffective in Jupiter's troposphere: CH4-NH3 coupling is inhibited by the physical separation of the CH4 photolysis region in the upper stratosphere from the NH3 photolysis and condensation region in the troposphere, and C2H2-NH3 coupling is inhibited by the low tropospheric abundance of C2H2. The upper limits from infrared and submillimetre observations can be used to place constraints on the production of HCN and other species from lightning and thundershock sources.
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Affiliation(s)
- Julianne I Moses
- Space Science Institute, 1602 Old Orchard Ln, Seabrook, TX 77586, USA.
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Arregi J, Rojas JF, Sánchez-Lavega A, Morgado A. Phase dispersion relation of the 5-micron hot spot wave from a long-term study of Jupiter in the visible. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002653] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Atreya SK, Wong MH, Owen TC, Mahaffy PR, Niemann HB, de Pater I, Drossart P, Encrenaz TH. A comparison of the atmospheres of Jupiter and Saturn: deep atmospheric composition, cloud structure, vertical mixing, and origin. PLANETARY AND SPACE SCIENCE 1999; 47:1243-1262. [PMID: 11543193 DOI: 10.1016/s0032-0633(99)00047-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We present our current understanding of the composition, vertical mixing, cloud structure and the origin of the atmospheres of Jupiter and Saturn. Available observations point to a much more vigorous vertical mixing in Saturn's middle-upper atmosphere than in Jupiter's. The nearly cloud-free nature of the Galileo probe entry site, a 5-micron hotspot, is consistent with the depletion of condensable volatiles to great depths, which is attributed to local meteorology. Somewhat similar depletion of water may be present in the 5-micron bright regions of Saturn also. The supersolar abundances of heavy elements, particularly C and S in Jupiter's atmosphere and C in Saturn's, as well as the progressive increase of C from Jupiter to Saturn and beyond, tend to support the icy planetesimal model of the formation of the giant planets and their atmospheres. However, much work remains to be done, especially in the area of laboratory studies, including identification of possible new microwave absorbers, and modelling, in order to resolve the controversy surrounding the large discrepancy between Jupiter's global ammonia abundance, hence the nitrogen elemental ratio, derived from the earth-based microwave observations and that inferred from the analysis of the Galileo probe-orbiter radio attenuation data for the hotspot. We look forward to the observations from Cassini-Huygens spacecraft which are expected to result not only in a rich harvest of information for Saturn, but a better understanding of the formation of the giant planets and their atmospheres when these data are combined with those that exist for Jupiter.
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Affiliation(s)
- S K Atreya
- Department of Atmospheric, Oceanic and Space Sciences, The University of Michigan, Ann Arbor 48109-2143, USA.
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Niemann HB, Atreya SK, Carignan GR, Donahue TM, Haberman JA, Harpold DN, Hartle RE, Hunten DM, Kasprzak WT, Mahaffy PR, Owen TC, Way SH. The composition of the Jovian atmosphere as determined by the Galileo probe mass spectrometer. JOURNAL OF GEOPHYSICAL RESEARCH 1998; 103:22831-45. [PMID: 11543372 DOI: 10.1029/98je01050] [Citation(s) in RCA: 266] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The Galileo probe mass spectrometer determined the composition of the Jovian atmosphere for species with masses between 2 and 150 amu from 0.5 to 21.1 bars. This paper presents the results of analysis of some of the constituents detected: H2, He, Ne, Ar, Kr, Xe, CH4, NH3, H2O, H2S, C2 and C3 nonmethane hydrocarbons, and possibly PH3 and Cl. 4He/H2 in the Jovian atmosphere was measured to be 0.157 +/- 0.030. 13C/C12 was found to be 0.0108 +/- 0.0005, and D/H and 3He/4He were measured. Ne was depleted, < or = 0.13 times solar, Ar < or = 1.7 solar, Kr < or = 5 solar, and Xe < or = 5 solar. CH4 has a constant mixing ratio of (2.1 +/- 0.4) x 10(-3) (12C, 2.9 solar), where the mixing ratio is relative to H2. Upper limits to the H2O mixing ratio rose from 8 x 10(-7) at pressures <3.8 bars to (5.6 +/- 2.5) x 10(-5) (16O, 0.033 +/- 0.015 solar) at 11.7 bars and, provisionally, about an order of magnitude larger at 18.7 bars. The mixing ratio of H2S was <10(-6) at pressures less than 3.8 bars but rose from about 0.7 x 10(-5) at 8.7 bars to about 7.7 x 10(-5) (32S, 2.5 solar) above 15 bars. Only very large upper limits to the NH3 mixing ratio have been set at present. If PH3 and Cl were present, their mixing ratios also increased with pressure. Species were detected at mass peaks appropriate for C2 and C3 hydrocarbons. It is not yet clear which of these were atmospheric constituents and which were instrumentally generated. These measurements imply (1) fractionation of 4He, (2) a local, altitude-dependent depletion of condensables, probably because the probe entered the descending arm of a circulation cell, (3) that icy planetesimals made significant contributions to the volatile inventory, and (4) a moderate decrease in D/H but no detectable change in (D + 3He)/H in this part of the galaxy during the past 4.6 Gyr.
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Affiliation(s)
- H B Niemann
- Goddard Space Flight Center, Greenbelt, Maryland, USA
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Ragent B, Colburn DS, Rages KA, Knight TCD, Avrin P, Orton GS, Yanamandra-Fisher PA, Grams GW. The clouds of Jupiter: Results of the Galileo Jupiter Mission Probe Nephelometer Experiment. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je00353] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Roos-Serote M, Drossart P, Encrenaz T, Lellouch E, Carlson RW, Baines KH, Kamp L, Mehlman R, Orton GS, Calcutt S, Irwin P, Taylor F, Weir A. Analysis of Jupiter north equatorial belt hot spots in the 4-5 μm range from Galileo/near-infrared mapping spectrometer observations: Measurements of cloud opacity, water, and ammonia. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01049] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Orton GS, Fisher BM, Baines KH, Stewart ST, Friedson AJ, Ortiz JL, Marinova M, Ressler M, Dayal A, Hoffmann W, Hora J, Hinkley S, Krishnan V, Masanovic M, Tesic J, Tziolas A, Parija KC. Characteristics of the Galileo probe entry site from Earth-based remote sensing observations. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je02380] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Seiff A, Kirk DB, Knight TCD, Young RE, Mihalov JD, Young LA, Milos FS, Schubert G, Blanchard RC, Atkinson D. Thermal structure of Jupiter's atmosphere near the edge of a 5-μm hot spot in the north equatorial belt. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01766] [Citation(s) in RCA: 250] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Folkner WM, Woo R, Nandi S. Ammonia abundance in Jupiter's atmosphere derived from the attenuation of the Galileo probe's radio signal. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01635] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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