Credit: ESO/R. Dong et al.; ALMA (ESO/NAOJ/NRAO)
This image from the Atacama Large Millimeter/submillimeter Array (ALMA) shows MWC 758, a young star that is approaching adulthood
and surrounded by knotty, irregular rings of cosmic dust, three of
which can be seen here. Unusually, these rings are elliptical in shape
rather than being perfectly circular — making this the first discovery
of an intrinsically elliptical protoplanetary disc with ALMA!
The
outer and inner rings each contain one particularly bright clump,
visible as arcs of yellow. Additionally there appear to be spiral arms
traced out within the dust, as well as a core dust-free cavity that is
slightly off-centre. These are all features that hint at the presence of
unseen planets. As planets form, they gravitationally interact with the
disc and create various telltale features and structures. Astronomers
can thus observe a system like MWC 758 and not only infer the existence
of potential hidden planets, but also estimate their masses, locations,
and orbits.
This is a wonderful example of the planet-finding
power of ALMA. Using the observatory to study such dusty discs allows
scientists to investigate the very first stages of planet formation in a
bid to understand how these infant systems form and evolve. Learning
more about planetary systems throughout the cosmos may help us know more
about how the Solar System formed, and how it evolved to become the
cosmic home we live in today.
Source: ESO/Potw
