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Jovian Infrared Auroral Mapper

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JIRAM
JIRAM data on Jupiter's southern lights, August 2016
Jovian "Hotspot" in visible (top) and near infrared (bottom) from a previous mission.

Jovian Infrared Auroral Mapper (JIRAM) is an instrument on the Juno spacecraft in orbit of the planet Jupiter. It is an image spectrometer and was contributed by Italy.[1] Similar instruments are on ESA Rosetta, Venus Express, and Cassini-Huygens missions.[1] The primary goal of JIRAM is to probe the upper layers of Jupiter's atmosphere down to pressures of 5–7 bars (72–102 pound/square inch) at infrared wavelengths in the 2–5 μm interval using an imager and a spectrometer.[1] The Jupiter's atmosphere and auroral regions are targeted for study.[2] In particular it has been designed to study the dynamics and chemistry in the atmosphere, perhaps determining the how Jovian hot spots form.[3]

H+
3
ions, ammonia, and phosphine can be mapped.[4] The ion of Hydrogen H+
3
is rare on Earth, but is one of the most common ions in the universe and known as protonated molecular hydrogen or the trihydrogen cation.[5]

Despite the intense magnetosphere of Jupiter, the JIRAM is expected to be operational for at least the first eight orbits.[6]

Previously Jupiter was observed by an Infrared imaging spectrometer called NIMS (Near-Infrared Mapping Spectrometer) on the Galileo Jupiter orbiter.[7] JIRAM was used to observe Earth during its flyby en route to Jupiter.[8] These observations were used to help calibrate the instrument, and the lunar observations were actually a critical planned step in preparing the instrument for observations at Jupiter.[9] The polar orbit of the Juno mission permits to get unprecedented observations of the planet. In particular, the polar regions, that where never observed before Juno, can be observed with high spatial resolution.

On August 27, 2016, JIRAM observed Jupiter at infrared wavelengths.[10] The first science observation in space was conducted on Earth's Moon in October 2013.[11]

The JIRAM project was started by Professor Angioletta Coradini, however she died in 2011.[12] The instrument was developed from Leonardo under the directions and supervision of the Institute for Space Astrophysics and Planetogy (IAPS) which is part of the Italian National Institute for Astrophysics and was funded by the Italian Space Agency.[13] Dr. Alberto Adriani of IAPS is presently the responsible of the JIRAM project.

In March 2018, results from JIRAM were released showing both the North and south poles have a central cyclone surrounded by addition cyclones.[14] The north cycle was surrounded by 8 cyclones, while the southern cyclone was surrounded by five.[14] By this time Juno had completed 10 close passes for science observations, since arriving in Jupiter's orbit on July 4, 2016.[14] The first science pass occurred on August 28, 2016, and JIRAM was operated during that pass.[15]

Various results, including a 3-D movie a flyover of the north pole of Jupiter with JIRAM data were released at the European Geosciences Union General Assembly in April 2018.[16]

JIRAM's spin-compensation mirror is stuck since PJ44, but the instrument is operational.[17]

Specifications

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  • Mass: 8 kg (17.6 pounds)[18]
  • Max power use: 16.7 watts[18]
  • Observation range: 2–5 micron wavelength light[18]

Observations

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Using data from JIRAM, a computer-generated view of Jupiter's north pole[19]

See also

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References

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  1. ^ a b c "Juno - Spacecraft: Instruments - JIRAM". Archived from the original on 2016-02-04. Retrieved 2016-02-17.
  2. ^ Adriani, A; Coradini, A; Filacchione, G; Lunine, JI; Bini, A; Pasqui, C; Calamai, L; Colosimo, F; Dinelli, BM; Grassi, D; Magni, G; Moriconi, ML; Orosei, R (2015-09-28). "JIRAM, the image spectrometer in the near infrared on board the Juno mission to Jupiter". Astrobiology. 8 (3): 613–22. Bibcode:2008AsBio...8..613A. doi:10.1089/ast.2007.0167. PMID 18680411.
  3. ^ Adriani, Alberto; Coradini, Angioletta; Filacchione, Gianrico; Lunine, Jonathan I.; Bini, Alessandro; Pasqui, Claudio; Calamai, Luciano; Colosimo, Fedele; Dinelli, Bianca M. (2008-06-01). "JIRAM, the image spectrometer in the near infrared on board the Juno mission to Jupiter". Astrobiology. 8 (3): 613–622. Bibcode:2008AsBio...8..613A. doi:10.1089/ast.2007.0167. ISSN 1557-8070. PMID 18680411.
  4. ^ P. Irwin (2009). Giant Planets of Our Solar System: Atmospheres, Composition, and Structure. Springer. p. 352. ISBN 9783540851585.
  5. ^ Carrington, Alan; R. McNab, Iain (1989). "The infrared predissociation spectrum of triatomic hydrogen cation (H3+)". Accounts of Chemical Research. 22 (6): 218–222. doi:10.1021/ar00162a004.
  6. ^ "Understanding Juno's Orbit: An Interview with NASA's Scott Bolton". Universe Today. 2016-01-08. Retrieved 6 February 2016.
  7. ^ "About Jiram | INAF-IAPS". www.iaps.inaf.it. Archived from the original on 2016-08-09. Retrieved 2017-02-07.
  8. ^ Adriani, A.; Moriconi, M. L.; Mura, A.; Tosi, F.; Sindoni, G.; Noschese, R.; Cicchetti, A.; Filacchione, G. (2016). "Juno's Earth flyby: the Jovian infrared Auroral Mapper preliminary results | ISAC - CNR". Astrophysics and Space Science. 361 (8): 272. Bibcode:2016Ap&SS.361..272A. doi:10.1007/s10509-016-2842-9. S2CID 125056540. Archived from the original on 2016-12-20. Retrieved 2017-02-07.
  9. ^ Adriani, A.; Moriconi, M. L.; Mura, A.; Tosi, F.; Sindoni, G.; Noschese, R.; Cicchetti, A.; Filacchione, G. (2016-08-01). "Juno's Earth flyby: the Jovian infrared Auroral Mapper preliminary results". Astrophysics and Space Science. 361 (8): 272. Bibcode:2016Ap&SS.361..272A. doi:10.1007/s10509-016-2842-9. ISSN 0004-640X. S2CID 125056540.
  10. ^ "Juno Captures Jupiter's Glow in Infrared Light". www.jpl.nasa.gov. Archived from the original on 2016-09-09. Retrieved 2017-02-07.
  11. ^ Adriani, A.; Moriconi, M. L.; Mura, A.; Tosi, F.; Sindoni, G.; Noschese, R.; Cicchetti, A.; Filacchione, G. (2016-07-19). "Juno's Earth flyby: the Jovian infrared Auroral Mapper preliminary results". Astrophysics and Space Science. 361 (8): 272. Bibcode:2016Ap&SS.361..272A. doi:10.1007/s10509-016-2842-9. ISSN 0004-640X. S2CID 125056540.
  12. ^ Adriani, Alberto; Filacchione, Gianrico; Iorio, Tatiana Di; Turrini, Diego; Noschese, Raffaella; Cicchetti, Andrea; Grassi, Davide; Mura, Alessandro; Sindoni, Giuseppe (2014-10-01). "JIRAM, the Jovian Infrared Auroral Mapper". Space Science Reviews. 213 (1–4): 393–446. Bibcode:2017SSRv..213..393A. doi:10.1007/s11214-014-0094-y. ISSN 0038-6308. S2CID 11739752.
  13. ^ "Jiram team | INAF-IAPS". www.iaps.inaf.it. Archived from the original on 2017-02-08. Retrieved 2017-02-07.
  14. ^ a b c Greicius, Tony (2018-03-07). "NASA Juno Findings - Jupiter's Jet-Streams Are Unearthly". NASA. Retrieved 2018-04-04.
  15. ^ "Juno Makes First Science Pass at Jupiter - Sky & Telescope". Sky & Telescope. 2016-09-05. Retrieved 2018-04-04.
  16. ^ "NASA's Juno Mission Provides Infrared Tour of Jupiter's North Pole". NASA/JPL. Retrieved 2018-12-26.
  17. ^ Rogers, John. "JunoCam at PJ57: Part I: Io" (PDF). britastro.org. Retrieved 2 April 2024.
  18. ^ a b c "Instrument Overview – Juno". spaceflight101.com. Retrieved 2017-02-07.
  19. ^ "NASA's Juno Mission Provides Infrared Tour of Jupiter's North Pole". Jet Propulsion Laboratory.
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