An Interacting Binary System Powers Precessing Outflows of an Evolved Star

• Published in: Science (American Association for the Advancement of Science) Vol. 338; no. 6108; pp. 773 - 775
• Main Authors: BOFFIN, Henri M. J, MISZALSKI, Brent, RAUCH, Thomas, JONES, David, CORRADI, Romano L. M, NAPIWOTZKI, Ralf, DAY-JONES, Avril C, KÖPPEN, Joachim
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 09.11.2012; The American Association for the Advancement of Science
• Subjects: Astronomy; Astrophysics; Binary system; Binary systems; Companion stars; Earth, ocean, space; Exact sciences and technology; Faint blue stars (including blue stragglers), white dwarfs, degenerate stars, nuclei of planetary nebulae; Interstellar medium (ism) and nebulae in milky way; Jets; Nebulae; Normal stars (by class): general or individual; Planetary nebulae; Spectra; Stars; Stars & galaxies; Stellar system evolution; Stellar systems. Galactic and extragalactic objects and systems. The universe; Chile; Planetary nebulae; Asymmetry; Astrophysical jets; Accretion disks; Binary stars; Gaseous shell
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1225386

Stars are generally spherical, yet their gaseous envelopes often appear nonspherical when ejected near the end of their lives. This quirk is most notable during the planetary nebula phase, when these envelopes become ionized. Interactions among stars in a binary system are suspected to cause the asymmetry. In particular, a precessing accretion disk around a companion is believed to launch point-symmetric jets, as seen in the prototype Fleming 1. Our finding of a post-common-envelope binary nucleus in Fleming 1 confirms that this scenario is highly favorable. Similar binary interactions are therefore likely to explain these kinds of outflows in a large variety of systems.