Winton Exoplanet Fellow 2019
Dr Thomas Louden, a postdoctoral researcher at the University of Warwick, discovered while researching for his PhD that the way light dips as a planet orbits in front of a star can provide information about that planet’s climate and weather patterns.
Dr Louden’s research uses techniques including transmission spectroscopy, as well as software he has developed for calculating secondary eclipses and phase curves, to better understand the constituents of an exoplanet’s atmosphere.
Exoplanet atmospheres are extremely diverse, but to date there have been few good explanations for this rich variety. Dr Louden’s Winton Exoplanet Fellowship proposal centred on the prospect of gaining insights into the atmospheric characteristics of exoplanets, including wind speed and cloud formation.
To achieve these insights, Dr Louden will use software that applies transmission spectroscopy to identify the Doppler shift of the spectral lines. This software allows him to measure the velocity of material in exoplanets’ atmospheres.
Understanding the climate and weather patterns of exoplanets ought to help us assess their potential habitability. Dr Louden will initially study “hot Jupiter” giant exoplanets that orbit far closer to stars. But he intends to use larger, more powerful telescopes under construction to study the colder atmospheres of small rocky exoplanets in due course.
Winton Exoplanet Fellow 2018
Dr Cassandra Hall, a postdoctoral research associate in theoretical astrophysics at the University of Leicester, will use state-of-the art computational techniques to focus on improving our fundamental understanding of exoplanet formation, through simulations of these exoplanets in their birth environment – a circumstellar disc around the host star.
While there are many ways to detect exoplanets, observing forming exoplanets cannot be done directly, since they are either too cold to emit sufficient photons, or there is too much other material around the disc obscuring the light. What can be done, however, is looking at the signatures they leave in the disc. This is a bit like guessing the size and shape of animals from footprints in the sand - but instead, these planets create ring-like or spiral-like features in a disc.
These signatures can be observed using interferometry, a technique where many antennae work together to improve resolution and sensitivity. But to understand these signatures we need advanced computational techniques, such as simulating the gas of the disc, known as hydrodynamics simulations, or creating a synthetic telescope image, by simulating photons.
Dr Hall proposes to develop models of discs and planets that will provide a consistent theoretical framework to explain or predict the range of exoplanet and disc parameters that create signposts of exoplanet formation.
Winton Exoplanet Fellow 2018
Dr Edward Gillen, a postdoctoral researcher in astrophysics at the University of Cambridge, will monitor several young open star clusters to search for young transiting “hot Jupiter” planets to better understand the formation and early evolution of planetary systems.
The term “hot Jupiter” planets describes those planets that have gaseous structures akin to Jupiter’s, but by contrast orbit their star with relatively short orbital periods. The majority of giant planet formation happens within a few million years with some planets eventually migrating inwards towards their host star.
Dr Gillen’s fellowship proposal is to find the detectable hot Jupiter planets and observe them in orbit around young stars, that is stars that range in age from a million- to a billion-years-old.
To do this, Dr Gillen will study data from NGTS – the Next Generation Transit Survey – which comprises 12 robotic telescopes in Chile. The hope is to gain a better understanding of the processes that drive planet migration, as well as the timescales involved, and to measure fundamental properties such as mass and radius at young ages.
