The gaseous, dusty disks surrounding newly born stars can reveal a wealth of information about how distant stellar systems form and evolve. In a new study, scientists have now watched the interaction of two such disks in a stellar fly-by.
In the past decade, new instrumentation has led to a dramatic improvement in our views of circumstellar environments. We’ve spotted remarkable structure in the dusty disks that surround newborn stars — including, in many cases, pronounced spiral arms.
An example of spiral arms detected in a protoplanetary disk, MWC 758. [NASA/ESA/ESO/M. Benisty et al]The presence of these spiral arms has provoked much discussion and debate. Are they caused by gravitational instabilities in the gas and dust? Or are they produced by perturbations from unseen, newborn planets orbiting within the disks? While both of these explanations could be at play in different systems, there’s an additional possibility to consider: the arms could be excited by tidal interactions with another star.
In a new study led by Luis Zapata (UNAM Radio Astronomy and Astrophysics Institute, Mexico), a team of scientists has used the sensitive and high-angular-resolution observations of the Atacama Large Millimeter/submillimeter Array (ALMA), located in Chile, to understand how ...