Uncovering the birthplaces of planets with the SKA

Advancing our understanding of how habitable planets form is one of the key science drivers of the SKA telescopes. Now a team of astronomers, led by Dr John Ilee at the University of Leeds in the UK, has performed the first investigation into the capability of the SKA-Mid telescope to observe the structure of protoplanetary discs, the birthplace of planets.

As planets form from the collision and coalescence of dust particles, they create structure in the disk, carving out concentric gaps at their location. Analysis of this structure can provide crucial information on the composition of the disk and the properties of the planets themselves. Dr Ilee’s team has created a model of a protoplanetary disk similar to the famous HL Tau star-disk system, which they have used to simulate the observations that will be obtained by the SKA-Mid telescope when it is fully operational.

Simulated SKA-Mid observations (Band 5b, 67 mas) of a protoplanetary disk host to three giant planets (left), with a representation of our own Solar System on the same scale (right).

Credit: John D. Ilee, University of Leeds (Ilee et al. 2020, MNRAS, 498, 5116).

The team has confirmed that SKA-Mid will be able to detect emission from centimetre-sized pebbles, allowing them to analyse the structure created in the disk as planets form, shedding light on a crucial step in the formation of planets. As a result of its large field of view, SKA-Mid will be able to observe dozens of protoplanetary disks simultaneously, providing robust tests of planet formation. “Understanding how the raw material for planet formation behaves is essential if we are to understand how planetary systems, like our own Solar System, come into existence. SKA-Mid will allow us to observe this clearly for the first time,” Dr Ilee says.

By Hilary Kay (The University Of Manchester – UK SKA)

Read more in our Let’s talk about... the origins of life article in this edition.