From Molecular Clouds to Exoplanets
Lead Research Organisation:
UNIVERSITY OF EXETER
Department Name: Physics
Abstract
The past decade has been characterised by a huge interest in the study of low mass stars (stars as or less massive than our Sun), brown dwarfs (failed stars unable to sustain nuclear fusion but which form like stars) and exoplanets (planets orbiting around other stars than the Sun). Now, about 500 exoplanets have been yet discovered and many more are expected with the space mission Kepler or large surveys like the UK program Superwasp, making the field of exoplanet one of the fastest growing areas of astrophysics.
With the development of infrared telescopes and near-IR surveys, a wealth of data for low mass stars and brown dwarfs has also become available. Their study is particularly important in an astrophysical context, knowing that most stars in our Galaxy are smaller than the Sun. Major observational efforts are devoted to star forming regions and very young stars, providing the basis for a better understanding of the very early phases of stellar evolution and most importantly of the fundamental process of star formation. Despite great progress on the theoretical and observational fronts, many pending questions remain regarding the whole process of star formation, starting with the gravitational collapse and fragmentation of a molecular cloud. This produces embryos of stars (the so-called proto-star) surrounded by an accretion disk where eventually conditions for rocky terrestrial and gas giant planets formation are met. This picture shows that stars and planets share a common origin. They also share common physical processes which play key roles on their interior and atmosphere structures and on their evolutionary properties, like convection and magnetism. The studies of these two populations of astrophysical bodies are closely interrelated, not only in terms of formation process, but also in terms of physical properties.
We thus propose a consistent research programme devoted to the understanding of (i) star and planet formation, from the collapse of molecular clouds to the formation of proto-stars and proto-planets, and (ii) stellar and planetary physics appropriate for the description of stellar and substellar objects' interiors and atmospheres (solar type and low mass stars, brown dwarfs, exoplanets). This programme plans to address several key questions in these areas combining high quality observations with state-of-the-art theoretical calculations and modelling.
On the theoretical front, we plan to develop advanced numerical simulations to understand convective transport, dynamo generation and magnetism in low mass stars and brown dwarfs and to describe irradiation-induced dynamics in exoplanets. Regarding the formation of these objects, we will use state-of-the-art simulations to study the effect of radiative feedback on star cluster formation and the process of planet formation based on self-consistent models of the interaction between protoplanet and circumstellar disk. We will also address the question of triggered star formation by the most luminous members of a star forming cluster using sophisticated radiation hydrodynamics models.
On the observational front, pending questions regarding the properties of molecular clouds will be addressed, namely
how star formation rates in these clouds depends on the local gas density and how giant molecular clouds form and collapse. A final major part of the proposal is dedicated to the thriving field of exoplanets: the detection of planets with direct imaging using one of the leading facility in the world, namely the Gemini telescopes, and the observation of exoplanet atmospheres, using the Hubble Space Telescope and the spanish GTC 10.4-m telescope.
With the development of infrared telescopes and near-IR surveys, a wealth of data for low mass stars and brown dwarfs has also become available. Their study is particularly important in an astrophysical context, knowing that most stars in our Galaxy are smaller than the Sun. Major observational efforts are devoted to star forming regions and very young stars, providing the basis for a better understanding of the very early phases of stellar evolution and most importantly of the fundamental process of star formation. Despite great progress on the theoretical and observational fronts, many pending questions remain regarding the whole process of star formation, starting with the gravitational collapse and fragmentation of a molecular cloud. This produces embryos of stars (the so-called proto-star) surrounded by an accretion disk where eventually conditions for rocky terrestrial and gas giant planets formation are met. This picture shows that stars and planets share a common origin. They also share common physical processes which play key roles on their interior and atmosphere structures and on their evolutionary properties, like convection and magnetism. The studies of these two populations of astrophysical bodies are closely interrelated, not only in terms of formation process, but also in terms of physical properties.
We thus propose a consistent research programme devoted to the understanding of (i) star and planet formation, from the collapse of molecular clouds to the formation of proto-stars and proto-planets, and (ii) stellar and planetary physics appropriate for the description of stellar and substellar objects' interiors and atmospheres (solar type and low mass stars, brown dwarfs, exoplanets). This programme plans to address several key questions in these areas combining high quality observations with state-of-the-art theoretical calculations and modelling.
On the theoretical front, we plan to develop advanced numerical simulations to understand convective transport, dynamo generation and magnetism in low mass stars and brown dwarfs and to describe irradiation-induced dynamics in exoplanets. Regarding the formation of these objects, we will use state-of-the-art simulations to study the effect of radiative feedback on star cluster formation and the process of planet formation based on self-consistent models of the interaction between protoplanet and circumstellar disk. We will also address the question of triggered star formation by the most luminous members of a star forming cluster using sophisticated radiation hydrodynamics models.
On the observational front, pending questions regarding the properties of molecular clouds will be addressed, namely
how star formation rates in these clouds depends on the local gas density and how giant molecular clouds form and collapse. A final major part of the proposal is dedicated to the thriving field of exoplanets: the detection of planets with direct imaging using one of the leading facility in the world, namely the Gemini telescopes, and the observation of exoplanet atmospheres, using the Hubble Space Telescope and the spanish GTC 10.4-m telescope.
Planned Impact
We expect that several of the techniques we develop will have applications outside astronomy, and we will continue to ensure we are connected with the appropriate communities to disseminate them. Primary areas for knowledge exchange are supercomputing, fluid dynamics, atmospheric and solar modelling and statistics.
The science in this proposal most likely to have a broad impact is the work on the atmospheres of extra-solar planets. The understanding developed from this work may well have an impact on our understanding of the Earth's climate, with the potential for wide economic benefits. This was one of the reasons we organised the first "Exoclimes" conference to link scientists working on the Earth and other Solar System planets with those working in exo-planet atmospheres. Further linkage is provided through the three professorial positions in the mathematics department which are jointly funded by the Met Office, whose interests include climate modelling. Similarly the work on the solar dynamo may have climate impacts, but also links to our understanding of the Earth's interior, with an obvious dissemination route via Zhang, as he is editor-in-chief of the journal "Physics of Earth and Planetary Interiors".
Computational fluid dynamics has a wide range of applications in engineering as well as in the entertainment industry for special effects, and the uses of high performance computing are even broader. We will continue to exchange knowledge in these fields via special interest groups within the UK and Europe, as well as through exchange of personnel.
Science is part of the UK's culture, and the academics involved in this proposal have developed a diverse and active outreach programme over the last few years. This programme has the additional aim of encouraging young people into science, which will have long-term benefits for the UK economy. As a result, we have deliberately aimed a significant part of our programme at school children. Over the three years since our "fun, informative and inspiring" International Year of Astronomy Open Evening (2009), we have actively increased our public outreach programme, offering talks, hands-on activities and demonstrations to around 2000 local people, roughly half of them under 18. This is in addition to the more conventional effort of individual members of staff talking to astronomy societies and other interested groups. Over the course of this grant, we propose to expand our visits to secondary schools, reaching the scientists of the future and key in the widening participation agenda.
Finally the post-docs and graduate students working on this programme will gain skills which are highly sought after by employers outside the academic field; our PhD students have moved into scientific publishing and non-academic research, in addition to those who have continued in academia.
The science in this proposal most likely to have a broad impact is the work on the atmospheres of extra-solar planets. The understanding developed from this work may well have an impact on our understanding of the Earth's climate, with the potential for wide economic benefits. This was one of the reasons we organised the first "Exoclimes" conference to link scientists working on the Earth and other Solar System planets with those working in exo-planet atmospheres. Further linkage is provided through the three professorial positions in the mathematics department which are jointly funded by the Met Office, whose interests include climate modelling. Similarly the work on the solar dynamo may have climate impacts, but also links to our understanding of the Earth's interior, with an obvious dissemination route via Zhang, as he is editor-in-chief of the journal "Physics of Earth and Planetary Interiors".
Computational fluid dynamics has a wide range of applications in engineering as well as in the entertainment industry for special effects, and the uses of high performance computing are even broader. We will continue to exchange knowledge in these fields via special interest groups within the UK and Europe, as well as through exchange of personnel.
Science is part of the UK's culture, and the academics involved in this proposal have developed a diverse and active outreach programme over the last few years. This programme has the additional aim of encouraging young people into science, which will have long-term benefits for the UK economy. As a result, we have deliberately aimed a significant part of our programme at school children. Over the three years since our "fun, informative and inspiring" International Year of Astronomy Open Evening (2009), we have actively increased our public outreach programme, offering talks, hands-on activities and demonstrations to around 2000 local people, roughly half of them under 18. This is in addition to the more conventional effort of individual members of staff talking to astronomy societies and other interested groups. Over the course of this grant, we propose to expand our visits to secondary schools, reaching the scientists of the future and key in the widening participation agenda.
Finally the post-docs and graduate students working on this programme will gain skills which are highly sought after by employers outside the academic field; our PhD students have moved into scientific publishing and non-academic research, in addition to those who have continued in academia.
Publications
Drummond B
(2019)
The carbon-to-oxygen ratio: implications for the spectra of hydrogen-dominated exoplanet atmospheres
in Monthly Notices of the Royal Astronomical Society
Ayliffe B
(2012)
On the accumulation of planetesimals near disc gaps created by protoplanets Planetesimal accumulation near gaps
in Monthly Notices of the Royal Astronomical Society
Drabek E
(2012)
Molecular line contamination in the SCUBA-2 450 and 850 µm continuum data Line contamination in SCUBA-2 continuum data
in Monthly Notices of the Royal Astronomical Society
Kong D
(2015)
An exact solution for arbitrarily rotating gaseous polytropes with index unity
in Monthly Notices of the Royal Astronomical Society
King R
(2012)
Testing the universality of star formation - II. Comparing separation distributions of nearby star-forming regions and the field Testing the universality of star formation - II
in Monthly Notices of the Royal Astronomical Society
Acreman D
(2015)
Modelling multiwavelength observational characteristics of bow shocks from runaway early-type stars
in Monthly Notices of the Royal Astronomical Society
Ripple F
(2013)
CO abundance variations in the Orion Molecular Cloud
in Monthly Notices of the Royal Astronomical Society
Lines S
(2019)
Overcast on Osiris: 3D radiative-hydrodynamical simulations of a cloudy hot Jupiter using the parametrized, phase-equilibrium cloud formation code EddySed
in Monthly Notices of the Royal Astronomical Society
Sing D
(2012)
GTC OSIRIS transiting exoplanet atmospheric survey: detection of sodium in XO-2b from differential long-slit spectroscopy GTC OSIRIS transiting exoplanet atmospheric survey
in Monthly Notices of the Royal Astronomical Society
Sing D
(2013)
HST hot-Jupiter transmission spectral survey: evidence for aerosols and lack of TiO in the atmosphere of WASP-12b
in Monthly Notices of the Royal Astronomical Society
De Rosa R
(2012)
The Volume-limited A-Star (VAST) survey - II. Orbital motion monitoring of A-type star multiples Orbital monitoring of A-type star multiples
in Monthly Notices of the Royal Astronomical Society
Heyer M
(2012)
Trans-Alfvénic motions in the Taurus molecular cloud Trans-Alfvénic motions in the Taurus cloud
in Monthly Notices of the Royal Astronomical Society
Brunt C
(2015)
Power-law tails in probability density functions of molecular cloud column density
in Monthly Notices of the Royal Astronomical Society
Bate M
(2014)
Collapse of a molecular cloud core to stellar densities: stellar-core and outflow formation in radiation magnetohydrodynamic simulations
in Monthly Notices of the Royal Astronomical Society
Lorén-Aguilar P
(2015)
Two-fluid dust and gas mixtures in smoothed particle hydrodynamics II: an improved semi-implicit approach
in Monthly Notices of the Royal Astronomical Society
Mayne N
(2012)
Bayesian fitting of Taurus brown dwarf spectral energy distributions SED fitting
in Monthly Notices of the Royal Astronomical Society
Huitson C
(2013)
An HST optical-to-near-IR transmission spectrum of the hot Jupiter WASP-19b: detection of atmospheric water and likely absence of TiO
in Monthly Notices of the Royal Astronomical Society
Husnoo N
(2012)
Observational constraints on tidal effects using orbital eccentricities? Observational constraints on tidal effects
in Monthly Notices of the Royal Astronomical Society
Haworth T
(2015)
On the relative importance of different microphysics on the D-type expansion of galactic H ii regions
in Monthly Notices of the Royal Astronomical Society
Bate M
(2012)
Stellar, brown dwarf and multiple star properties from a radiation hydrodynamical simulation of star cluster formation Stellar and multiple star properties
in Monthly Notices of the Royal Astronomical Society
Pont F
(2013)
The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations
in Monthly Notices of the Royal Astronomical Society
Moore T
(2015)
The JCMT Plane Survey: early results from the l = 30° field
in Monthly Notices of the Royal Astronomical Society
Wilson P
(2015)
GTC OSIRIS transiting exoplanet atmospheric survey: detection of potassium in HAT-P-1b from narrow-band spectrophotometry?
in Monthly Notices of the Royal Astronomical Society
Buckle J
(2012)
The JCMT Legacy Survey of the Gould Belt: mapping 13CO and C18O in Orion A GBS HARP survey: Orion A
in Monthly Notices of the Royal Astronomical Society
Ayliffe B
(2012)
The growth and hydrodynamic collapse of a protoplanet envelope Hydrodynamic collapse models
in Monthly Notices of the Royal Astronomical Society
Lorén-Aguilar P
(2016)
Toroidal vortices as a solution to the dust migration problem
in Monthly Notices of the Royal Astronomical Society: Letters
Kong D
(2015)
Wind-induced odd gravitational harmonics of Jupiter
in Monthly Notices of the Royal Astronomical Society: Letters
Price D
(2012)
Collimated jets from the first core
in Monthly Notices of the Royal Astronomical Society: Letters
Sing DK
(2016)
A continuum from clear to cloudy hot-Jupiter exoplanets without primordial water depletion.
in Nature
Weber M
(2017)
The Suppression and Promotion of Magnetic Flux Emergence in Fully Convective Stars
in Proceedings of the International Astronomical Union
Lewis P
(2012)
An Earth Observation Land Data Assimilation System (EO-LDAS)
in Remote Sensing of Environment
Prior C
(2012)
On the Shape of Force-Free Field Lines in the Solar Corona
in Solar Physics
Dunham M
(2013)
THE LUMINOSITIES OF PROTOSTARS IN THE SPITZER c2d AND GOULD BELT LEGACY CLOUDS
in The Astronomical Journal
Kraus S
(2013)
RESOLVING THE GAP AND AU-SCALE ASYMMETRIES IN THE PRE-TRANSITIONAL DISK OF V1247 ORIONIS
in The Astrophysical Journal
Monnier J
(2017)
Polarized Disk Emission from Herbig Ae/Be Stars Observed Using Gemini Planet Imager: HD 144432, HD 150193, HD 163296, and HD 169142
in The Astrophysical Journal
Monnier J
(2019)
Multiple Spiral Arms in the Disk around Intermediate-mass Binary HD 34700A
in The Astrophysical Journal
Tremblin P
(2015)
FINGERING CONVECTION AND CLOUDLESS MODELS FOR COOL BROWN DWARF ATMOSPHERES
in The Astrophysical Journal
Evans T
(2013)
THE DEEP BLUE COLOR OF HD 189733b: ALBEDO MEASUREMENTS WITH HUBBLE SPACE TELESCOPE /SPACE TELESCOPE IMAGING SPECTROGRAPH AT VISIBLE WAVELENGTHS
in The Astrophysical Journal
Tremblin P
(2019)
Thermo-compositional Diabatic Convection in the Atmospheres of Brown Dwarfs and in Earth's Atmosphere and Oceans
in The Astrophysical Journal
Geroux C
(2014)
RADIAL STELLAR PULSATION AND THREE-DIMENSIONAL CONVECTION. III. COMPARISON OF TWO-DIMENSIONAL AND THREE-DIMENSIONAL CONVECTION EFFECTS ON RADIAL PULSATION
in The Astrophysical Journal
Hinkley S
(2015)
EARLY RESULTS FROM VLT SPHERE: LONG-SLIT SPECTROSCOPY OF 2MASS 0122-2439 B, A YOUNG COMPANION NEAR THE DEUTERIUM BURNING LIMIT
in The Astrophysical Journal
Mayne N
(2019)
The Limits of the Primitive Equations of Dynamics for Warm, Slowly Rotating Small Neptunes and Super Earths
in The Astrophysical Journal
Weber M
(2016)
MODELING THE RISE OF FIBRIL MAGNETIC FIELDS IN FULLY CONVECTIVE STARS
in The Astrophysical Journal
Perna R
(2012)
THE EFFECTS OF IRRADIATION ON HOT JOVIAN ATMOSPHERES: HEAT REDISTRIBUTION AND ENERGY DISSIPATION
in The Astrophysical Journal
Ireland L
(2018)
The Radius and Entropy of a Magnetized, Rotating, Fully Convective Star: Analysis with Depth-dependent Mixing Length Theories
in The Astrophysical Journal
Baraffe I
(2012)
OBSERVED LUMINOSITY SPREAD IN YOUNG CLUSTERS AND FU Ori STARS: A UNIFIED PICTURE
in The Astrophysical Journal
Sadavoy S
(2013)
THE HERSCHEL AND JCMT GOULD BELT SURVEYS: CONSTRAINING DUST PROPERTIES IN THE PERSEUS B1 CLUMP WITH PACS, SPIRE, AND SCUBA-2
in The Astrophysical Journal
Geroux C
(2015)
RADIAL STELLAR PULSATION AND THREE-DIMENSIONAL CONVECTION. IV. FULL AMPLITUDE THREE-DIMENSIONAL SOLUTIONS
in The Astrophysical Journal
Cleeves L
(2015)
INDIRECT DETECTION OF FORMING PROTOPLANETS VIA CHEMICAL ASYMMETRIES IN DISKS
in The Astrophysical Journal
Hatchell J
(2012)
THE SPITZER SURVEY OF INTERSTELLAR CLOUDS IN THE GOULD BELT. V. OPHIUCHUS NORTH OBSERVED WITH IRAC AND MIPS
in The Astrophysical Journal
Description | The science produced by this award has been used for public engagement and outreach activities above all in schools. |
First Year Of Impact | 2012 |
Sector | Education |
Impact Types | Cultural |
Description | ERC advanced Baraffe |
Amount | € 2,500,000 (EUR) |
Organisation | European Research Council (ERC) |
Sector | Public |
Country | Belgium |
Start | 04/2013 |
End | 04/2018 |
Description | ERC advanced Bate |
Amount | £1,800,000 (GBP) |
Organisation | European Research Council (ERC) |
Sector | Public |
Country | Belgium |
Start | 01/2014 |
End | 12/2019 |
Description | ERC starting Browning |
Amount | £1,500,000 (GBP) |
Organisation | European Research Council (ERC) |
Sector | Public |
Country | Belgium |
Start | 01/2014 |
End | 12/2019 |
Description | ERC starting grant Sing |
Amount | £1,500,000 (GBP) |
Organisation | European Research Council (ERC) |
Sector | Public |
Country | Belgium |
Start | 01/2014 |
End | 12/2019 |
Description | scientific collaboration |
Organisation | Institute of Physics in Rostov-on-Don (Russia) |
Country | Russian Federation |
Sector | Academic/University |
PI Contribution | common papers (Baraffe et al. 2012, Vorobyov 2013) |
Collaborator Contribution | commons papers (Baraffe et al. 2012, Vorobyov 2013) |
Impact | Baraffe et al. 2012 Vorobyov et al. 2013 |
Start Year | 2011 |
Description | scientific collaboration |
Organisation | Meteorological Office UK |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | secondment/papers |
Collaborator Contribution | secondment/papers |
Impact | Mayne et al. 2013, 2014 Amundsen et al. 2014 |
Start Year | 2010 |
Description | BBC Stargazing Live |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | National |
Primary Audience | Media (as a channel to the public) |
Results and Impact | wide TV audience may contacts from schools/press after the show |
Year(s) Of Engagement Activity | 2013 |
Description | Institute of Physics schools lecture tours in the Southwest and Channel Islands |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | Regional |
Primary Audience | Schools |
Results and Impact | Lecture on 'Newborn Stars and Unexplored Planets' highlighting Exeter Astrophysics research and STFC facilities Further invitation to give lectures to schools |
Year(s) Of Engagement Activity | 2012,2013 |