ESO: Planet-forming Lifeline Discovered in a Binary System

[bystander]

Planet-forming Lifeline Discovered in a Binary Star System
European Southern Observatory | ALMA | 2014 Oct 29

ALMA Examines Ezekiel-like “Wheel in a Wheel” of Dust and Gas

[url=http://www.eso.org/public/images/eso1434a/][b][i]Artist’s impression of the double-star system GG Tauri-A[/i][/b][/url] [b][i]Credit: ESO/L. Calçada, ALMA (ESO/NAOJ/NRAO)[/i][/b]

---

---

For the first time, researchers using ALMA have detected a streamer of gas flowing from a massive outer disc toward the inner reaches of a binary star system. This never-before-seen feature may be responsible for sustaining a second, smaller disc of planet-forming material that otherwise would have disappeared long ago. Half of Sun-like stars are born in binary systems, meaning that these findings will have major consequences for the hunt for exoplanets. The results are published in the journal Nature on 30 October 2014.

A research group led by Anne Dutrey from the Laboratory of Astrophysics of Bordeaux, France and CNRS used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe the distribution of dust and gas in a multiple-star system called GG Tau-A. This object is only a few million years old and lies about 450 light-years from Earth in the constellation of Taurus (The Bull).

Like a wheel in a wheel, GG Tau-A contains a large, outer disc encircling the entire system as well as an inner disc around the main central star. This second inner disc has a mass roughly equivalent to that of Jupiter. Its presence has been an intriguing mystery for astronomers since it is losing material to its central star at a rate that should have depleted it long ago. ...

ALMA Examines Ezekiel-like "Wheel in a Wheel" of Dust & Gas
National Radio Astronomy Observatory | ALMA | 2014 Oct 29

Possible planet formation in the young, low-mass, multiple stellar system GG Tau A - Anne Dutrey et al

• Nature 514 600 (30 Oct 2014) DOI: 10.1038/nature13822 (pdf)

[BDanielMayfield]

Very nice finding. Systems with two or more stars are sometimes discounted in considerations of planet numbers. When reading about exoplanets one of the most common introductory statements is often something like, "in single star systems like ours ...". It's only natural to focus our attention first on "systems like ours", but since multiple star systems are more numerous than solitary ones there could be an enormous number of exoplanets awaiting discovery in multi-star systems.