PhDs in Planetary Physics

Oxford’s Planetary Physics group specialises in the exploration of planetary atmospheres and surfaces, with expertise ranging from hardware development to spectral analysis; ground-based astronomy to spacecraft operations; and numerical simulations of planetary climate to laboratory experiments of geophysical fluid dynamics. Our interests extend from the environments found in our own Solar System to the extreme conditions found in Extrasolar Planets and Brown Dwarfs. An overview of our research can be found on the Planetary Science page, and an overview of exoplanet research at Oxford can be found on the Oxford Exoplanet page.

Several projects are available within the group in the coming year. They typically involve the measurement and modelling of visible and infrared spectra of planetary objects, using these data to understand and model their environmental conditions (atmospheric dynamics, composition and clouds; thermophysical properties and compositions of surfaces). Next year we shall be looking for students in the following areas:

  • The transit spectra of exoplanets
  • Characterising the thermal alteration history of carbonaceous meteorites to help interpret data from NASA’s OSIRIS-REx asteroid sample return mission
  • Re-constructing Primitive Meteoritic Materials in the Laboratory to support remote sensing of asteroids and comets
  • Ground and space-based telescope observations of the Ice Giants (Uranus and Neptune)
  • Spectroscopic monitoring of Jupiter’s atmospheric dynamics and chemistry to support planetary missions
  • Dynamical modelling of storms and eddies in the atmospheres of Jupiter and Saturn
  • Modelling the circulation of slowly rotating planets, such as Venus and Titan
  • Climate modelling of terrestrial planets fluid or rocky super-Earths
  • European Research Council project EXOCONDENSE, on effect of condensable atmospheric constituents on climate dynamics of exoplanet atmospheres.

2018 project descriptions

Infrared remote sensing of the Ice Giants

Supervisor: Patrick Irwin (AOPP)
Project ref: AOPP/PGJI/1/2018

Voyager 2 flew past Uranus and Neptune in 1986 and 1989, and provided our only close-up views of these ice giant worlds. Now, a quarter-century later, the ice giants are recognised as key destinations for future planetary missions and as our closest examples of a planetary class that appears commonplace throughout our galaxy. The Voyager flybys revealed dynamic worlds quite unlike the familiar banded structures of Jupiter and Saturn, but the brevity of these encounters prevented detailed scrutiny. Uranus was shown to be rather sluggish, whereas Neptune featured dynamic cloud activity and vortices. This difference has never been satisfactorily explained and subsequent ground based observations have since suggested that the activity on both of these planets varies hugely with time. This project aims to construct a three-dimensional understanding of an ice giant atmosphere to connect activity in the tropospheric weather layer (where convective clouds form and are sheared apart) to the middle atmosphere (the stratosphere, dominated by wave activity and photochemistry). The candidate would attempt to link changes in cloud activity and albedo in reflectivity spectra (wavelengths < 3 µm) with the temperature and composition of the ice giants, as measured in thermal-infrared spectra (wavelengths> 5 µm), to reveal the underlying dynamics and circulations of these ice giant atmospheres.

This project will utilise infrared observations from a variety of ground-based and space-based observatories. Uranus observations taken near spring equinox in 2007 by the Spitzer Space Telescope will be used to measure the longitudinal variations of temperature and composition in the stratosphere, attempting to relate these variations to wave activity generated by tropospheric weather. As well as revealing the chemistry of Uranus’ middle atmosphere, this will also aid in our understanding of vertical energy transport processes on the ice giants. In addition, ground-based infrared imaging and spectroscopy of the ice giants from the world’s leading observatories (e.g., Gemini, ESO’ Very Large Telescope (VLT) and Subaru), and also planned observations from the James Webb Space Telescope (JWST), due for launch in 2019, will be used to determine the spatial variation, vertical distribution and temporal evolution of temperature and cloud activity, to better understand the condensation processes at work in these frigid atmospheres.

The key result of this project will be a self-consistent picture of the circulation and cloud-forming processes at work on the ice giants, paving the way for future atmospheric studies by visiting spacecraft. The successful candidate would be joining a well-established planetary data analysis group that is actively involved in observational astronomy and planetary missions (e.g., the recently completed Cassini mission at Saturn). Analysis of spectral data will be performed using the suite of radiative transfer and retrieval software developed at Oxford, collectively known as NEMESIS. The candidate would be involved with new observation proposals at ground-based observatories, such as VLT and would gain experience of acquiring, reducing and interpreting infrared imaging and spectroscopy from a range of world-class telescope facilities, both on the ground and in space.

This project will be computationally intensive using Fortran, IDL and others, so a physics/computing/mathematics background is preferred, and a first degree in Physics or Mathematics is required.

Visible and Infrared remote sensing of the Gas Giants

Supervisor: Patrick Irwin (AOPP)
Project ref: AOPP/PGJI/2/2018

The clouds of the Solar System’s Gas Giants (Jupiter and Saturn) are amongst the most beautiful and complex phenomena displayed by the planets. Their spatial distribution reveals the forces and energy exchange mechanisms (e.g., moist convection) shaping the banded appearance of the planetary weather layers; their vertical structure tells us about the composition and cloud microphysics; and their colour reveals the chemical alteration of aerosols in a giant planet atmosphere. While most clouds are white, the clouds of Jupiter and Saturn are coloured with various hues of yellow and red, but the nature of these colours, or ‘chromophores,’ has yet to be determined, and remains an enduring mystery.

To better understand these planets, we can turn to a number of ground-based and space-based observatories. ESO’s Very Large Telescope (VLT) in Chile, is equipped with a number of instruments, ranging from the visible to the infrared. For example, the MUSE (Multi Unit Spectroscopic Explorer) instrument has provided an unprecedented opportunity to study the clouds, dynamics and composition of the giant planet atmospheres at a spatial and spectral resolution never before possible. MUSE measures spectral ‘cubes’ in which each pixel of the 300 x 300 field of view is a complete spectrum covering the range spectral 480 to 930 nm. These ‘cubes’ allow us to map the spatial distribution of the clouds and colouring agents, estimate cloud top levels and determine spatial variations in methane abundance (for Uranus and Neptune) and ammonia (Jupiter and Saturn). While other ground-based and space-based instruments can provide partial coverage of these wavelengths (usually as images in discrete filters), only MUSE provides the unique combination of spatial and spectral coverage, which makes it a very powerful tool for studying clouds in giant planet atmospheres. At near-infrared wavelengths, VLT’s SINFONI instrument provides a similar near-infrared mapping spectroscopy capability, and the data can be used to better constrain vertical cloud structure. At even longer wavelengths, instruments such as VISIR provide thermal mapping that can be used to determine the vertical and spatial distribution of temperature and gaseous abundances. In addition to these ground-based facilities, NASA’s James Webb Space Telescope (JWST) is scheduled for launch in 2019 and is planned to make many observations of the giant planets over a wide wavelength range that will need to be understood and interpreted.

The successful candidate would be joining a well-established planetary data analysis group that is actively involved in observational astronomy and planetary missions (e.g., the recently completed Cassini mission at Saturn). In this project, the student will analyse existing VLT/MUSE Giant Planet observations and participate in proposing and reducing future observations, gaining excellent experience in telescopic observations and analysis. The spectral cubes will be analysed with a sophisticated multiple-scattering radiative transfer model, NEMESIS, previously developed to model observations of solar system planets. The timescale of the project would mean that the student would have real data to analyse from the start. These data will be used to look for seasonal changes and also monitor occasional cloud upheaval events, such as the great storm on Saturn in 2010, the NEB outbreak on Jupiter in 2012. In addition, our VLT/MUSE observations of Jupiter (which are ongoing) provide invaluable context observations for the NASA/Juno mission, which arrived in Jupiter orbit in July 2016. This spacecraft has been placed into a polar orbit, with a low periapsis over Jupiter’s north pole. The mission is primarily designed to determine Jupiter’s internal structure by mapping its gravitational field, but remote sensing cameras also observe narrow ‘strips’ of Jupiter as the spacecraft flies over the north pole. Interpreting these observations requires that we know how the observed ‘strips’ relate to the overall appearance and cloud structure of Jupiter. While simple ground-based imaging will be able to relate the strips to the wider context, only VLT/MUSE is able to provide the spectral component, relating any composition/chromophore changes detected by Juno with the wide Jovian atmosphere.

This project will be computationally intensive using Fortran, IDL and others, so a physics/computing/mathematics degree is preferred.

Modelling the spectra of exoplanets

Supervisor: Patrick Irwin (AOPP) and Suzanne Aigrain (Astrophysics)
Project ref: AOPP/PGJI/3/2018

The discovery of exoplanets in 1995, just over twenty years ago, has ushered in a new age in scientific exploration. Over 5000 exoplanets have now been discovered and the study of these worlds has profound implications for our understanding of human evolution and our place in the universe. New missions, such as the James Webb Space Telescope (JWST), now due for launch in 2019, will return better-than-ever transit spectra of exoplanets, where the planet passes either in front of or behind the host star, and also allow direct-imaging observations. In parallel with this, ground-based direct-imaging spectroscopy instruments, such as VLT/SPHERE and Gemini/GPI, promise to revolutionise the field of ground-based exoplanet spectral measurements by also recording the reflection/emission spectra of some of these worlds directly. Further in the future, potential dedicated exoplanet missions such as the proposed Ariel spacecraft could enable greatly improved atmospheric characterisation through more precise transit spectra measurements, and missions such as WFIRST could record directly-imaged planetary reflection/emission spectra.

Modelling radiative transfer in these atmospheres underpins the scientific exploitation of these observations, but many challenges are faced compared with Solar System analyses; the most important of these challenges are the very high atmospheric temperatures of some of the ‘Hot Jupiters’ and also the absorbing and scattering effect of clouds, whose broad spectral features can mask and obscure gaseous features. In this project the student will take Oxford’s existing sophisticated radiative transfer and retrieval model, NEMESIS, which was first developed for solar system planetary analysis, and use it to model the observed spectra of exoplanets to determine their gaseous composition and thermal structure. This will be done both with our traditional optimal estimation approach and also using Markov Chain Monte Carlo and nested sampling methods, which have recently been implemented within the NEMESIS framework. In particular, accurate modelling of condensates in exoplanetary atmospheres is now thought to be crucial in reliably interpreting exoplanet spectra. The student will thus investigate the influence of including different cloud species on the spectra produced by NEMESIS, and consider the likelihood of occurrence of such clouds in exoplanetary atmospheres. These studies will be used to inform how future observations of JWST and other possible missions should best be designed to maximise their scientific return. With a start date in 2018, the student would be well placed to analyse data collected during JWST’s first year of operations, and will analyse data from early release science (ERS) proposals and hopefully contribute to applications for further time.

This project will be computationally intensive using Fortran, IDL and others, so a physics/computing/mathematics degree is preferred.

Exoplanet climate dynamics

Supervisor: Raymond Pierrehumbert (AOPP)
Project ref: AOPP/RTP/1-4/2018

The newly discovered exoplanets present possibilities for a diverse range of climate situations not encountered in our own solar system. The demands of this new subject challenge the limits of current modelling capabilities, and while they involve the same underlying physical components as are familiar from the Solar systems, these components are present in novel combinations. This project involves a range of modeling and theoretical activities aimed at understanding the new climates. There is a particular emphasis on identifying potentially observable consequences of various exoplanet climate phenomena. I am seeking up to four DPhil students for work in the general area of exoplanet climate modeling, with a particular emphasis on smaller planets (super-Earth size and below) which can have a more rich diversity of atmospheric compositions than the hydrogen-dominated gas giants, and offer a range of additional phenomena associated with the possibility of a condensed rocky, icy or liquid surface. In all of our work, there is an emphasis on maintaining an appropriate balance between theoretical work or idealized modeling aimed at elucidating fundamental principles, and work with more comprehensive general circulation models.

Two DPhil students are sought for exoclimate projects in one or more of the following general areas: (1) Atmospheric escape and implications for habitability of M-star planets, (2) Baroclinic instability on tide-locked slowly rotating planets (3) Exchange of volatiles between planetary interiors and atmospheres, including effects of magma oceans on atmospheres and implications of the deep carbon cycle and CO2 outgassing on the outer edge of the habitable zone. (4) Transient phenomena in exoplanet atmospheres, their use in contraining planetary characteristics, and prospects for detection with future observational programs. (5) Spatially inhomogeneous chemistry of planetary atmospheres driven by mixing due to idealized large scale flow. In addition to these specific project areas, I am open to suggestions from students who wish to take the initiative in defining their own research direction within the general area of exoplanet climate and climate evolution.

Two additional studentships are available on the ERC EXOCONDENSE project, aimed at generalizing “moist climate dynamics” from the familiar case of condensable water vapor on Earth to the greater variety of condensable substances that may be present in exoplanet atmospheres. Topics of interest include both generalized moist convection and its parameterization and condensation effects (including clouds) in planetary scale dynamics. Further information on EXOCONDENSE can be found at the EXOCONDENSE project page.

These projects require a thorough understanding of fundamental physics, including thermodynamics, mechanics and electromagnetic radiation, as well as a facility with analysis of mathematical models. Familiarity with physical chemistry is also desirable. Hence, a first degree in Physics, Mathematics or a related discipline is required. The projects involve considerable use of computational techniques, so basic familiarity with numerical analysis and familiarity with programming techniques in some computer language is required. The main programming languages used are Python and Fortran, but prior experience with these specific languages, while desirable, is not required.

The climate and circulation of Venus

Supervisor: Peter Read (AOPP)
Project ref: AOPP/PLR/1/2018

Venus is an Earth-like planet with a substantial atmosphere composed of CO2 but rotates relatively slowly compared to the Earth. This places its atmosphere in a very different dynamical regime from that of the Earth, and its cloud tops are observed, for example, to rotate much faster about its planetary rotation axis than the underlying planet, quite unlike the Earth's atmosphere. The detailed mechanism that causes the Venus atmosphere to "super-rotate" is beginning to become clear, and dynamical models developed recently (in Oxford and elsewhere) have begun to reproduce this basic behavior. From such models, it seems clear that the mechanism driving the strong super-rotation on Venus may be qualitatively different from the other slowly rotating planetary body with a substantial atmosphere, Titan (the moon of Saturn), with Venus being strongly affected by the intense contrast in solar heating between the day- and night-sides of the planet. Such diurnal effects appear to be relatively weak on Titan however. These two bodies may also represent prototypes of classes of planets that may also be found orbiting other stars.

Despite these successes, even the most realistic and sophisticated models of the Venus atmosphere have proved unable to reproduce the observed structure of the super-rotation in its deep atmosphere, and a number of aspects of the circulation of both planets remain poorly understood. In this project, therefore, we will use a range of numerical simulation models to explore both the tropical and extra-tropical circulation of Venus. These models will include both a highly idealized 3D general circulation model with simplified forcing parameterizations and a much more sophisticated model of the Venus atmosphere, currently based on the UK Met Office Unified Model. The latter includes realistic physical representations of radiative transfer in the Venus atmosphere, surface topography and the formation of clouds. One focus for Venus will be on improving the representation of the deep atmosphere, below the visible clouds, and its interaction with the underlying surface. Another focus could be on the clouds themselves, how and where they are formed and how they interact with the atmospheric circulation and the absorption and emission of radiation. Comparison with observations e.g. from ESA's Venus Express and JAXA’s Akatsuki missions will be made wherever possible with the aim of identifying processes that can be further explored in future space missions.

This project will be computationally intensive, using programming languages such as Fortran, IDL, MATLAB and others, so a physics/computing/mathematics background is preferred, and a first degree in Physics, Mathematics or a related discipline is required.

Modelling and observations of large-scale storms and vortices on Jupiter and Saturn

Supervisor: Peter Read (AOPP)
Project ref: AOPP/PLR/2/2018

The atmospheres of Jupiter and Saturn are characterized at their cloud tops by patterns of winds organized into many intense, parallel jet streams, aligned east-west, within which we observe a rich diversity of eddies, vortices, waves and convective storms. The origin of these eddies is often far from clear, and the whole problem is compounded by our inability to observe their structure below the tops of the NH3 clouds that visualize them. Recent modeling and observational studies (in Oxford and elsewhere) suggest that the zonal jet streams owe much of their origin to nonlinear interactions with the eddies themselves, but the details are still not fully understood. The structure of many of the large eddies in the vertical is also quite uncertain, so we need to rely on fundamental theory and models to infer what may be going on in the deep atmosphere.

In this project, we will make use of a numerical model of the atmospheres of Jupiter and Saturn, based on the MITgcm, that will have sufficient horizontal and vertical resolution to explore the possible structure and origin of vortices, waves and storms in association with strong jet streams. The model has been under development in Oxford for some time now, and includes a number of facilities to represent the main thermodynamic forcing processes (radiative transfer, convection and moist processes) and the formation and transport of clouds. It is currently being optimized for global simulations at moderate resolution, but in the present project it is envisaged to use the model to cover just a limited region of the atmosphere in the horizontal with very high spatial resolution. Model simulations will be carried out to explore analogues of features such as Jupiter's Great Red Spot and Oval BA, Saturn's "Ribbon Wave" and "Polar Hexagon", the giant convective storm of 2010, and compact polar vortices seen on both planets. Simulations will be compared with detailed observations of winds, temperature and other variables where possible, with the possibility of deriving new wind measurements from existing imagery of these features if required. The overall aim will be to try to identify conditions under which features resembling those observed can be reproduced within model simulations and to infer aspects of their vertical structure that may eventually be amenable to observational tests.

This project will be computationally intensive, using programming languages such as Fortran, IDL, MATLAB and others, so a physics/computing/mathematics background is preferred, and a first degree in Physics, Mathematics or a related discipline is required.

Understanding the thermal transfer on airless bodies in the Solar System: Application to NASA’s Lunar Reconnaissance Orbiter, OSRIS-REx missions Solar System resource mapping

Supervisors: Neil Bowles (AOPP) and Tristram Warren (AOPP)

Project ref: AOPP/NEB/1/2018

This project will take the latest measurements being made by NASA’s OSIRIS-REx asteroid sample return mission and Lunar Reconnaissance orbiter missions and use them to help us learn more about the fundamental processes that redistribute heat on an airless bodies surface. This is essential if we want to understand the surfaces of planets such as Mercury or search for resources on asteroids.

Thermal infrared measurements of airless bodies can tell us a huge amount of information about their surfaces including their surface temperature, composition and texture. To obtain this information the measured thermal emission from the Moon or asteroid must be compared to a computer 3D thermal model of the surface. Typically, these models combine topography and compositional data using a combination of ray tracing techniques and solutions to the 1D thermal diffusion equation. This allows the model to simulate the observations being made by a spacecraft.

These models generally do a good job at matching the measured temperatures from the e.g. the lunar surface; however, in regions where the incidence angle of the incoming solar light is low and the dominate source of heat transfer is thermal re-radiation they have significant errors. These are exactly the areas e.g. near the poles where there is the potential for trapped volatiles such as water ice. Most 3D thermal models assume that light is scattered equally in all directions - a Lambertian surface, however it is believed that this assumption is incorrect particularly at high incidence angles.

Here at Oxford Physics we are tackling this problem and have developed a unique piece of laboratory equipment known as a goniometer, similar to a 3D protractor. This instrument allows us to measure the angular distribution of emitted and scattered thermal radiation in a space-like environment that can then be used with a 3D thermal model. Samples used in the instrument are simulants of lunar-like materials and this project will give you chance to work both with the lab instrument and the computer based models.

Depending on the student this project could include helping to upgrade the goniometer to include a visible or infrared light source or developing our own 3D thermal model using ray-tracing type techniques.

Modeling thermal emission spectra of the Moon and other airless solar system bodies: application to Lunar Reconnaissance Orbiter and OSIRIS-REx asteroid sample return mission.

Supervisors: Neil Bowles (AOPP), Kerri Donaldson Hanna (AOPP) and Don Grainger (AOPP)

Project ref: AOPP/NEB/2/2018

Surface composition can tell planetary scientists a great deal about the processes that shape terrestrial solar system objects, such as magmatic evolution, impacts and space weathering. Visible and infrared spectra acquired by instruments such as the Moon Mineralogy Mapper and Diviner Lunar Radiometer are used to obtain compositional information, particularly mineral identification. While thermal infrared spectroscopy is a useful technique, its application is challenging as spectra are also influenced by mineral grain size, shape, packing, and surface texture. On an airless body, there is further complexity caused by the extreme thermal environment of these surfaces, with temperature changes of hundreds of Kelvin within the upper millimeter. The steep thermal gradient affects the positions and shapes of the diagnostic spectral features used to infer surface composition, especially for the grain sizes typical of lunar and asteroid regolith (<100μm).

This project involves contributing to the development of a radiative and thermal conductive heat transfer model of airless body regolith. One potential aspect of this is building up and validating the model itself. Possible options for this include: adding relevant materials to the model where data is available, investigating the effect of grain shape, testing ways of dealing with mineral mixtures and exploring inversion procedures. Model results will be compared to laboratory measurements taken in a lunar-like environment. Another potential aspect is conducting laboratory measurements of the optical properties of well-characterized materials. Radiative transfer models require optical constants (the wavelength-dependent real and imaginary indices of refraction) for each material that may be present. Despite being fundamental to understanding planetary surface composition, there are surprising number of common rock-forming minerals and planetary analogue materials for which these data are not available. This project can also include a laboratory component to help develop new models of these materials and provide a new source of optical constant data.

Understanding the spectrum of three-dimensional exo-atmospheres.

Supervisors: Vivien Parmentier (AOPP) and Patrick Irwin (AOPP)

Project ref: AOPP/VP/1/2018

The last decade has seen the discovery of thousands of exoplanets but, more excitingly, the characterization of their atmospheres has become possible. We now have spectra of dozens of planets, ranging from hot Jupiters, to warm Neptunes to temperate Earth-size worlds. In the hottest planets, which are easier to observe, molecules such as sodium, water, magnesium and carbon monoxide have already been detected. Quantifying their abundances remains the challenge of the coming decade.
The information we gather from exoplanet atmospheres only gives us a partial view of the atmosphere’s properties. We can measure physical quantities averaged over the limb of the planet during transit and over the dayside of the planet during secondary eclipse. For outstanding targets longitudinal information can be obtained by measuring the phase curve of the planet. Exoplanet atmospheres are, however, inherently three-dimensional objects. This is particularly true for the current sample of well characterized close-in, hot and tidally locked planets dominated by the intense and inhomogeneous irradiation they receive. Even more challenging are the clouds that have been detected in most planets studied so far. They often hide an unknown fraction of the atmosphere, leading to the biggest uncertainty in the determination of molecular abundances, typically of the order of a factor a hundred to ten thousands.

In the next five years three groundbreaking missions will be launched that will revolutionize our view of exoplanet atmospheres. TESS and CHEOPS will find and characterize thousands of new exoplanets of which hundreds will be orbiting very bright stars and become golden targets for atmospheric characterization. The James Webb Space Telescope and possibly the ARIEL mission will obtain spectra of around a hundred of planets with a quality orders of magnitude better than currently available data.

In this project, the student will learn how to use the radiative transfer code NEMESIS in order to calculate the transmission spectrum, the eclipse spectrum and the phase curve of more than 500 hot Jupiter global circulation models exploring key parameters of exoplanets atmospheres (equilibrium temperature, rotation period, gravity, metallicity, atmospheric drag). As a first step, the student will compare the spectrum from the 3D models and equivalent 1D spectrum used traditionally to interpret exoplanet’s atmospheres observations and highlight the biases produced by the 1D approach, particularly in the James Webb Space Telescope era. Then the student will incorporate the grid of calculated observables into the retrieval framework of NEMESIS, creating the first « 3D retrieval » framework able to interpret jointly the information gathered from transmission spectrum, emission spectrum and phase curve observations. Finally, the student will be reached how to use the global circulation model SPARC/MITgcm in order to refine or extend the grid of models as necessary, for exemple by adding the radiative feedback of cloud opacities directly inside the atmospheric circulation calculations. With a start date in 2018, the student would be well placed to analyse data collected during JWST’s first year of operations, and will analyse data from early release science (ERS) proposals and hopefully contribute to applications for further time.

This project will be computationally intensive using Fortran, IDL and others, so a physics/computing/mathematics degree is preferred.

Atmospheric circulation of hot gaseous exoplanets.

Supervisor: Vivien Parmentier (AOPP)

Project ref: AOPP/VP/2/2018

Most exoplanets for which atmospheric characterization is possible are tidally locked, hot, gaseous exoplanets named hot Jupiters. Their dayside is always facing the star while their nightside is never illuminated. A strong atmospheric circulation with km/s winds transfer energy from the dayside to the nightside of the planet, shaping the large-scale temperature, chemical and cloud maps of the planet.

With current facilities and coming observatories, the 2D (height-longitude) map of the temperature, the chemical composition and the cloud coverage have been observed for a dozen planets. In the next five to ten years, around a hundred exo-planets atmospheres should be characterized at this level, allowing the determination of trends between intrinsic planet properties such as rotation rate, equilibrium temperature and observables, such as temperature distribution, cloud distribution, wind speed etc.

In order to prepare and interpret coming observations, a change of scale is necessary on the theory side. The student will use a combination of analytical models and an already existing grid of ~500 global circulation models to understand the theoretical trends between atmospheric properties and planet properties. How the wind speed scales with equilibrium temperature? How the dayside mean temperature scales with atmospheric metallicity? How the day/night temperature contrast scales with rotation period? How the mean vertical transport varies with insolation?

The theoretical trends will first be compared to current observation of the transmission, emission spectrum and phase curves of hot Jupiters. Then the student will apply for telescope time with current facilities (such as the Hubble Space Telescope) or coming ones (such the James Webb Space Telescope) to test the validity of the theoretical predictions.

Following the student lead, the project could be extended toward the study of the atmospheric circulation of smaller (Neptune-size) planets and lead to the interpretation of Spitzer space telescope observations of the phase curve of the mysterious GJ436b that will be taken during 2018.