Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered a streamer of gas flowing from a massive outer disc toward the inner reaches of a young, low-mass binary star system GG Tau-A.
The never-before-seen feature may be responsible for sustaining a second, smaller disc of planet-forming material that otherwise would have disappeared long ago.
“We have demonstrated that the inner disks can be replenished with fresh material and are thereby potential sites of planet formation,” Emmanuel Di Folco, co-author of the study from the Laboratory of Astrophysics of Bordeaux, France told me. "Our finding with ALMA is that there is a large amount of cold material that flows into the cavity (from the outer ring) towards the inner disk(s) and stars. The infalling material can nurture the inner disk(s) and extend their lifetime on timescales long enough to sustain planet formation therein.”
The researchers detailed their findings in a paper to be published in the journal Nature on Oct. 30, 2014.