Imaging the Interaction of the Heliosphere with the Interstellar Medium from Saturn with Cassini

• Published in: Science (American Association for the Advancement of Science) Vol. 326; no. 5955; pp. 971 - 973
• Main Authors: Krimigis, S.M, Mitchell, D.G, Roelof, E.C, Hsieh, K.C, McComas, D.J
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 13-11-2009; The American Association for the Advancement of Science
• Subjects: Astronomy; Astrophysics; Characteristics and properties of the milky way; Earth, ocean, space; Exact sciences and technology; Heliopause; Heliosheath; Heliosphere; Incan culture; Interplanetary space; Ions; Magnetic fields; Protons; Saturn; Solar neighborhood; Solar system; Solar wind; Solar wind plasma; Stellar systems. Galactic and extragalactic objects and systems. The universe; Sun; Protons; Energetic neutral atom; Interstellar magnetic fields; Sun; Interstellar space; Heliosphere; Saturn planet; Local field; Space probe observation; Solar neighborhood; Solar atmosphere; Models; Cassini space probe; Interstellar matter
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1181079

We report an all-sky image of energetic neutral atoms (ENAs) >6 kilo-electron volts produced by energetic protons occupying the region (heliosheath) between the boundary of the extended solar atmosphere and the local interstellar medium (LISM). The map obtained by the Ion and Neutral Camera (INCA) onboard Cassini reveals a broad belt of energetic protons whose nonthermal pressure is comparable to that of the local interstellar magnetic field. The belt, centered at approximately 260° ecliptic longitude extending from north to south and looping back through approximately 80°, appears to be ordered by the local interstellar magnetic field. The shape revealed by the ENA image does not conform to current models, wherein the heliosphere resembles a cometlike figure aligned in the direction of Sun's travel through the LISM.