Our Research
Our group's interests are varied, but fall under a common theme of understanding nearby planets and stars. We use different telescopes, methods, and tools to achieve this goal. This page highlights just a few things that we've worked on recently or are working on currently. If you're interested in collaborating or joining us, reach out!
Enabling Science with TESS Full-Frame Images
Our group led the development of eleanor, an open-source python tool for the community to create light curves and remove instrumental systematics in TESS Full-Frame Image data. This tool has been used in hundreds of papers in the astronomical literature to date to (among other things) find planets, characterise supernovae, and better understand stellar pulsations. We are continuing to use eleanor and tools based on it to better understand stars across the sky, including young stars, binary systems, and evolved stars.
The Evolution of Stellar Activity Across the Main Sequence and in Time
Young stars have strong magnetic fields and rapid rotation, leading to large flares and photometric variability on short timescales. This can inhibit planet detection but also teach us about the intrinsic behaviour of these young stars and their disks from which planets form. We're interested in every piece of this puzzle!
The evolution of a star's magnetic activity has implications for habitability, and we're interested in using Kepler and TESS data to analyse how magnetically active regions change in time. We use long time baseline studies to look for signs of activity cycles and their variation, as well as statistical approaches to leverage as much information as possible from when transiting planets move across inhomogeneous stellar surfaces.
Detecting Dynamical Signatures of Circumbinary Planets
Circumbinary planets are those that, like Tatooine from Star Wars, orbit two stars instead of only one. The majority of these have been found via their transits, but this approach limits us to only those that are aligned with their stars and with our line of sight. We have begun a program to identify which binary stars may be orbited by a third object based off the dynamical perturbations these objects would impart on their host stars. By detecting signs of precession over long baselines, we can find systems which must host a companion, and use Doppler spectroscopy or astrometric monitoring to determine the precise nature of this companion. We've found a few dozen candidates so far, with hopefully many more to come!
This work is funded by the Australian Research Council Discovery Program.
Synergies between TESS and GALAH
GALAH, the GALactic Archeology with HERMES survey at the Anglo-Australian Telescope is in the process of obtaining R~28,000 spectra for approximately one million stars across the Southern sky. TESS has observed many of these same stars in its Full-Frame Images, and will continue to periodically do so for the rest of its mission. Spectra of a million stars, many of which host planets, enable us to answer questions about the relationship between elemental abundances and planet formation. In addition, we can compare spectroscopic tracers of stellar activity to photometric tracers of the same, understand the relationship between kinematic and gyrochonological age estimates for stars, and understand stellar multiplicity.
The Next Generation of Planet-Finding Instruments
We're interested in using data-driven models to push the limits of what can be found with upcoming state-of-the-art instruments that are designed to find planets. This is an international effort in which we're collaborating with colleagues in Australia and Europe. We are involved with the MARVEL spectrograph led by KU Leuven, to be located at La Palma, and the TOLIMAN astrometric mission to be launched by the University of Sydney to astrometrically identify planets in the nearest binary systems. These systems will both be able to detect small planets, in different ways, enabling us to measure masses of some of the smallest planets and better understand how magnetic activity evolves over stellar lifetimes.