Earliest recorded ground-based decameter wavelength observations of Saturn’s lightning during the giant E-storm detected by Cassini spacecraft in early 2006

Autor: E. P. Abranin, Helmut O. Rucker, Jean-Mathias Grießmeier, V. V. Zakharenko, M. L. Kaiser, D. A. Gurnett, Alain Lecacheux, K. M. Sidorchuk, William S. Kurth, Georg Fischer, N. N. Kalinichenko, I. S. Falkovich, A. A. Konovalenko, Philippe Zarka, K. Mylostna
Přispěvatelé: Institute of Radio Astronomy of NASU [Kharkiv] (IRA), National Academy of Sciences of Ukraine (NASU), Space Research Institute of Austrian Academy of Sciences (IWF), Austrian Academy of Sciences (OeAW), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Department of Physics and Astronomy, University of Iowa, University of Iowa [Iowa City], University of Basel (Unibas), Swiss Tropical and Public Health Institute [Basel], NASU-CNRS PICS Program 'Development of LF radioastronomy with ultrahigh sensitivity and resolution' (Grant 1.33.11), ANR-05-BLAN-0018,RADIO-EXOPLA(2005), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), ANR: NT05-1- 42530,Radio-Exopla
Rok vydání: 2013
Předmět:
Zdroj: Icarus
Icarus, Elsevier, 2013, 224 (1), pp.14-23. ⟨10.1016/j.icarus.2012.07.024⟩
Icarus, 2013, 224 (1), pp.14-23. ⟨10.1016/j.icarus.2012.07.024⟩
ISSN: 0019-1035
1090-2643
Popis: We report the history of the first recorded ground-based radio detection of Saturn’s lightning using the Ukrainian UTR-2 radiotelescope at frequencies from 20 to 25 MHz. The observations were performed between 29 January and 3 February 2006, during which lighting activity (E-storm) on Saturn was detected by the radio experiment onboard Cassini spacecraft. The minimum detectable flux density ( 1 σ -level) at UTR-2 reached 40 Jy ( 1 Jy = 10 - 26 W m - 2 Hz - 1 ) for narrowband observations ( Δ f = 10 kHz ) and 4 Jy for broadband observations ( Δ f = 1 MHz ), for an effective telescope area of ≈ 100 , 000 m 2 and integration time of 20 ms. Selection criteria including comparison of simultaneous ON/OFF-source observations were applied to distinguish detection of lightning-associated radio pulses from interference. This allowed us to identify about 70 events with signal-to-noise ratio more than 5. Measured flux densities (between 50 and 700 Jy) and burst durations (between 60 and 220 ms) are in good agreement with extrapolation of previous Cassini measurements to a ground-based observer. This first detection demonstrates the possibility of Solar System planetary lightning studies using large, present and future ground-based radio instruments. The developed methods of observations and identification criteria are also implemented on the UTR-2 radio telescope for the investigation of the next Saturn’s storms. Together with recently published UTR-2 measurements of activity measured after the 2006 storm reported here, the results have significant implications for detectable planetary radio emission in our Solar System and beyond.
Databáze: OpenAIRE