Markers of planet migration in the population of planetary cores
Lead Research Organisation:
University of Warwick
Department Name: Physics
Abstract
We now know of planets numbering in the thousands. This tells us that planets are common, enough to be a usual occurrence around stars like the sun. However, despite this increasing number of planets, finding out more detail about them is difficult. What are the planets made of, and how did they form and evolve to leave the planets we see? Finding out how other solar systems formed allows us to place our own Solar System in context. Perhaps we are typical, or perhaps unique - this knowledge changes how we think about the Earth and our life upon it.
One way to study how other planets form is to look at their cores. The planetary core shows the environment it began in, with its composition telling us what materials were present at its beginning, before it obtained an envelope of gas. We still do not know any great detail about the cores of Jupiter and Saturn, because their gas envelopes block the core from view, and the same is true of other worlds. But planets close to their host star receive a lot of light and energy, enough to evaporate the gas and reveal the core. By uncovering a new population of these planets, I want to find out the dominant composition of their cores, discovering if they formed differently from others. As such short period planets do not exist in the Solar System, I will be uncovering the evidence of a new type of planetary evolution and history.
One way to study how other planets form is to look at their cores. The planetary core shows the environment it began in, with its composition telling us what materials were present at its beginning, before it obtained an envelope of gas. We still do not know any great detail about the cores of Jupiter and Saturn, because their gas envelopes block the core from view, and the same is true of other worlds. But planets close to their host star receive a lot of light and energy, enough to evaporate the gas and reveal the core. By uncovering a new population of these planets, I want to find out the dominant composition of their cores, discovering if they formed differently from others. As such short period planets do not exist in the Solar System, I will be uncovering the evidence of a new type of planetary evolution and history.
Organisations
- University of Warwick (Fellow, Lead Research Organisation)
- National University of San Martin (Collaboration)
- Alan Turing Institute (Collaboration)
- University of Geneva (Collaboration)
- University of Porto (Collaboration)
- Massachusetts Institute of Technology (Collaboration)
- Laboratoire d'Astrophysique de Marseile (Collaboration)
People |
ORCID iD |
David John Armstrong (Principal Investigator / Fellow) |
Publications
McCormac James
(2019)
NGTS-10b: The shortest period hot Jupiter yet discovered
in arXiv e-prints
Sha Lizhou
(2022)
TESS spots a mini-neptune interior to a hot saturn in the TOI-2000 system
in arXiv e-prints
Santerne A.
(2019)
An extremely low-density and temperate giant exoplanet
in arXiv e-prints
Veras D
(2018)
Dynamical and Biological Panspermia Constraints Within Multi-planet Exosystems.
in Astrobiology
Lillo-Box J
(2023)
TOI-969: a late-K dwarf with a hot mini-Neptune in the desert and an eccentric cold Jupiter
in Astronomy & Astrophysics
Azevedo Silva T
(2022)
The HD 137496 system: A dense, hot super-Mercury and a cold Jupiter
in Astronomy & Astrophysics
Eigmüller P
(2019)
NGTS-5b: a highly inflated planet offering insights into the sub-Jovian desert
in Astronomy & Astrophysics
Lam K
(2018)
K2-265 b: a transiting rocky super-Earth
in Astronomy & Astrophysics
Lillo-Box J
(2020)
Masses for the seven planets in K2-32 and K2-233 Four diverse planets in resonant chain and the first young rocky worlds
in Astronomy & Astrophysics
Barros S
(2023)
The young mini-Neptune HD 207496b that is either a naked core or on the verge of becoming one
in Astronomy & Astrophysics
Lopez T
(2019)
Exoplanet characterisation in the longest known resonant chain: the K2-138 system seen by HARPS
in Astronomy & Astrophysics
Otegi J
(2021)
TESS and HARPS reveal two sub-Neptunes around TOI 1062
in Astronomy & Astrophysics
Grouffal S
(2022)
Rossiter-McLaughlin detection of the 9-month period transiting exoplanet HIP41378 d
in Astronomy & Astrophysics
Smith A
(2021)
NGTS-14Ab: a Neptune-sized transiting planet in the desert
in Astronomy & Astrophysics
Esposito M
(2019)
HD 219666 b: a hot-Neptune from TESS Sector 1
in Astronomy & Astrophysics
Fereshteh-Saniee N
(2022)
Quality Analysis of Weld-Line Defects in Carbon Fibre Reinforced Sheet Moulding Compounds by Automated Eddy Current Scanning
in Journal of Manufacturing and Materials Processing
Raynard L
(2018)
NGTS-2b: an inflated hot-Jupiter transiting a bright F-dwarf
in Monthly Notices of the Royal Astronomical Society
Bryant E
(2020)
NGTS-12b: A sub-Saturn mass transiting exoplanet in a 7.53 day orbit
in Monthly Notices of the Royal Astronomical Society
West R
(2020)
A long-period (P = 61.8 d) M5V dwarf eclipsing a Sun-like star from TESS and NGTS
in Monthly Notices of the Royal Astronomical Society
Battley M
(2022)
YOUNG Star detrending for Transiting Exoplanet Recovery (YOUNGSTER) - II. Using self-organizing maps to explore young star variability in sectors 1-13 of TESS data
in Monthly Notices of the Royal Astronomical Society
Chaushev A
(2019)
Classifying exoplanet candidates with convolutional neural networks: application to the Next Generation Transit Survey
in Monthly Notices of the Royal Astronomical Society
Schanche N
(2019)
Machine-learning approaches to exoplanet transit detection and candidate validation in wide-field ground-based surveys
in Monthly Notices of the Royal Astronomical Society
Jackson D
(2023)
The discovery of three hot Jupiters, NGTS-23b, 24b, and 25b, and updated parameters for HATS-54b from the Next Generation Transit Survey
in Monthly Notices of the Royal Astronomical Society
Bayliss D
(2018)
NGTS-1b: a hot Jupiter transiting an M-dwarf
in Monthly Notices of the Royal Astronomical Society
Battley M
(2020)
A search for young exoplanets in Sectors 1-5 of the TESS full-frame images
in Monthly Notices of the Royal Astronomical Society
Description | Habitability in the Universe Postgraduate training |
Geographic Reach | Local/Municipal/Regional |
Policy Influence Type | Influenced training of practitioners or researchers |
Impact | Over 100 students have taken the module, with uniformly positive feedback. |
URL | https://warwick.ac.uk/fac/cross_fac/iatl/study/postgraduate_modules_iatl/habitability/ |
Description | Frontier Research Guarantee |
Amount | £1,323,766 (GBP) |
Funding ID | EP/X027562/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start | 12/2022 |
End | 12/2027 |
Title | HARPS archival data - NCORES and NOMADS programs |
Description | Spectroscopic observations of several TESS candidate planets, which are made public on the ESO archive one year after observation. Observations cover over 140 nights of time on the HARPS spectrograph, and several tens of planetary systems. The dates cover observations taken from 2018 to 2023, and will continue. |
Type Of Material | Database/Collection of data |
Year Produced | 2019 |
Provided To Others? | Yes |
Impact | Ongoing publications and follow-up pf TESS planetary candidates. Archival studies looking at long term radial velocity variations and stellar characterisation will be enabled by this dataset. |
URL | http://archive.eso.org/wdb/wdb/adp/phase3_main/form |
Title | K2-138 HARPS radial velocities |
Description | VizieR online Data Catalogue associated with article published in journal Astronomy & Astrophysics with title 'Exoplanet characterisation in the longest known resonant chain: the K2-138 system seen by HARPS.' (bibcode: 2019A&A...631A..90L) |
Type Of Material | Database/Collection of data |
Year Produced | 2019 |
Provided To Others? | Yes |
Impact | Data required for publication. See publication table for citations and ongoing impact. |
URL | https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/631/A90 |
Title | K2-32 and K2-233 light and RV curves |
Description | VizieR online Data Catalogue associated with article published in journal Astronomy & Astrophysics with title 'Masses for the seven planets in K2-32 and K2-233. Four diverse planets in resonant chain and the first young rocky worlds.' (bibcode: 2020A&A...640A..48L) |
Type Of Material | Database/Collection of data |
Year Produced | 2020 |
Provided To Others? | Yes |
Impact | Data required for publication. See publication table for citations and ongoing impact. |
URL | https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/640/A48 |
Title | Kepler planet masses, radii and orbital periods |
Description | VizieR online Data Catalogue associated with article published in journal Astronomical Journal (AAS) with title 'A gap in the mass distribution for warm Neptune and terrestrial planets.' (bibcode: 2019ApJ...880L...1A) |
Type Of Material | Database/Collection of data |
Year Produced | 2021 |
Provided To Others? | Yes |
Impact | Data required for publication. See publication table for citations and ongoing impact. |
URL | https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/880/L1 |
Title | Near-resonance in a system of sub-Neptunes from TESS |
Description | VizieR online Data Catalogue associated with article published in journal Astronomical Journal (AAS) with title 'Near-resonance in a system of sub-Neptunes from TESS.' (bibcode: 2019AJ....158..177Q) |
Type Of Material | Database/Collection of data |
Year Produced | 2020 |
Provided To Others? | Yes |
Impact | Data required for publication. See publication table for citations and ongoing impact. |
URL | https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/158/177 |
Title | TESS and NGTS LCs and RVs of NGTS-11 |
Description | VizieR online Data Catalogue associated with article published in journal Astronomical Journal (AAS) with title 'NGTS-11 b (TOI-1847 b): a transiting warm Saturn recovered from a TESS single-transit event.' (bibcode: 2020ApJ...898L..11G) |
Type Of Material | Database/Collection of data |
Year Produced | 2021 |
Provided To Others? | Yes |
Impact | Data required for publication. See publication table for citations and ongoing impact. |
URL | https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/898/L11 |
Description | Collaboration with Machine Learning research group/Turing Institute |
Organisation | Alan Turing Institute |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Collaborative work whereby by team contributes field-expertise in terms of exoplanets, detection methods and data, and applies jointly developed machine learning techniques to our research |
Collaborator Contribution | A researcher associated with the Turing contributes expertise on state of the art machine learning techniques which we apply in our research. |
Impact | Publication - Exoplanet Validation with Machine Learning: 50 new validated Kepler planets (see publications). This was associated with a joint press release. In addition two jointly supervised students, one at 3rd year project level and one at Masters level. |
Start Year | 2018 |
Description | NCORES collaboration |
Organisation | Laboratoire d'Astrophysique de Marseile |
Country | France |
Sector | Academic/University |
PI Contribution | I am the PI of the collaboration. NCORES exists to coordinate, perform and publish spectroscopic characterisations of planets discovered near the photoevaporation gap, which hence may be exposed planetary cores. I organise the collaboration, PI the large HARPS program which obtains much of the relevant data, and coordinate outputs and publications. |
Collaborator Contribution | Geneva - The Geneva observatory has significant expertise on the spectrographs used, and lends significant manpower in analysing those data and troubleshooting any issues that arise, as well as performing planetary internal structure calculations. Porto - The team at Porto are experts on stellar characterisation and perform this stage of the analysis for all results LAM - The team at Marseilles perform planetary internal structure calculations and joint Bayesian fitting of datasets. |
Impact | Publication Outputs: 5 journal articles as detailed in publications section. Public datasets: The HARPS observations which form the backbone of the collaboration are made public after one year and archived by ESO. |
Start Year | 2018 |
Description | NCORES collaboration |
Organisation | University of Geneva |
Department | Geneva Observatory |
Country | Switzerland |
Sector | Academic/University |
PI Contribution | I am the PI of the collaboration. NCORES exists to coordinate, perform and publish spectroscopic characterisations of planets discovered near the photoevaporation gap, which hence may be exposed planetary cores. I organise the collaboration, PI the large HARPS program which obtains much of the relevant data, and coordinate outputs and publications. |
Collaborator Contribution | Geneva - The Geneva observatory has significant expertise on the spectrographs used, and lends significant manpower in analysing those data and troubleshooting any issues that arise, as well as performing planetary internal structure calculations. Porto - The team at Porto are experts on stellar characterisation and perform this stage of the analysis for all results LAM - The team at Marseilles perform planetary internal structure calculations and joint Bayesian fitting of datasets. |
Impact | Publication Outputs: 5 journal articles as detailed in publications section. Public datasets: The HARPS observations which form the backbone of the collaboration are made public after one year and archived by ESO. |
Start Year | 2018 |
Description | NCORES collaboration |
Organisation | University of Porto |
Country | Portugal |
Sector | Academic/University |
PI Contribution | I am the PI of the collaboration. NCORES exists to coordinate, perform and publish spectroscopic characterisations of planets discovered near the photoevaporation gap, which hence may be exposed planetary cores. I organise the collaboration, PI the large HARPS program which obtains much of the relevant data, and coordinate outputs and publications. |
Collaborator Contribution | Geneva - The Geneva observatory has significant expertise on the spectrographs used, and lends significant manpower in analysing those data and troubleshooting any issues that arise, as well as performing planetary internal structure calculations. Porto - The team at Porto are experts on stellar characterisation and perform this stage of the analysis for all results LAM - The team at Marseilles perform planetary internal structure calculations and joint Bayesian fitting of datasets. |
Impact | Publication Outputs: 5 journal articles as detailed in publications section. Public datasets: The HARPS observations which form the backbone of the collaboration are made public after one year and archived by ESO. |
Start Year | 2018 |
Description | NOMADS Collaboration |
Organisation | Laboratoire d'Astrophysique de Marseile |
Country | France |
Sector | Academic/University |
PI Contribution | Armstrong is the PI of this collaboration. The group of >30 academics and students works to characterise planets in the Neptunian desert, with the long term aim of revealing the demographics and statistical properties of the desert planet population. Our research team's contribution is in acquiring telescope time on the HARPS spectrograph, coordinating observations, targets, and the wider consortium, and providing strategic direction to the project. |
Collaborator Contribution | Different collaborators have different inputs. These include stellar characterisation, planetary internal structure modelling, false positive simulations, telescope observing, and photometric and spectroscopic followup of candidates. |
Impact | Publications in progress. |
Start Year | 2021 |
Description | NOMADS Collaboration |
Organisation | National University of San Martin |
Country | Argentina |
Sector | Academic/University |
PI Contribution | Armstrong is the PI of this collaboration. The group of >30 academics and students works to characterise planets in the Neptunian desert, with the long term aim of revealing the demographics and statistical properties of the desert planet population. Our research team's contribution is in acquiring telescope time on the HARPS spectrograph, coordinating observations, targets, and the wider consortium, and providing strategic direction to the project. |
Collaborator Contribution | Different collaborators have different inputs. These include stellar characterisation, planetary internal structure modelling, false positive simulations, telescope observing, and photometric and spectroscopic followup of candidates. |
Impact | Publications in progress. |
Start Year | 2021 |
Description | NOMADS Collaboration |
Organisation | University of Geneva |
Department | Geneva Observatory |
Country | Switzerland |
Sector | Academic/University |
PI Contribution | Armstrong is the PI of this collaboration. The group of >30 academics and students works to characterise planets in the Neptunian desert, with the long term aim of revealing the demographics and statistical properties of the desert planet population. Our research team's contribution is in acquiring telescope time on the HARPS spectrograph, coordinating observations, targets, and the wider consortium, and providing strategic direction to the project. |
Collaborator Contribution | Different collaborators have different inputs. These include stellar characterisation, planetary internal structure modelling, false positive simulations, telescope observing, and photometric and spectroscopic followup of candidates. |
Impact | Publications in progress. |
Start Year | 2021 |
Description | NOMADS Collaboration |
Organisation | University of Porto |
Country | Portugal |
Sector | Academic/University |
PI Contribution | Armstrong is the PI of this collaboration. The group of >30 academics and students works to characterise planets in the Neptunian desert, with the long term aim of revealing the demographics and statistical properties of the desert planet population. Our research team's contribution is in acquiring telescope time on the HARPS spectrograph, coordinating observations, targets, and the wider consortium, and providing strategic direction to the project. |
Collaborator Contribution | Different collaborators have different inputs. These include stellar characterisation, planetary internal structure modelling, false positive simulations, telescope observing, and photometric and spectroscopic followup of candidates. |
Impact | Publications in progress. |
Start Year | 2021 |
Description | TESS Follow-up Observing Program (TFOP) |
Organisation | Massachusetts Institute of Technology |
Country | United States |
Sector | Academic/University |
PI Contribution | I am the PI of a HARPS spectrograph program which follows up candidate TESS planets. The results of the follow-up are coordinated with the TFOP collaboration to avoid duplicating observations and maximise the efficiency of the TESS satellite and my HARPS program. |
Collaborator Contribution | MIT is the site of the TESS science office where TESS data is initially processed. TFOP is actually a wider collaboration involving a large number of institutes around the world, and coordinates follow-up activities to TESS planets. THE main team at MIT contribute to my research by releasing early lists of TESS planet candidates which allows me to save significant time in moving to planet characterisation. The amount of in-kind funding is an estimate but the time saved is substantial, and hence the in-kind funding is likely underestimated if anything. |
Impact | Publications: Several publications as detailed in the publications section. |
Start Year | 2019 |
Description | BBC Sky at Night interview |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | I was interviewed for the BBC 'Sky at Night' program, with the resulting episode broadcast nationally and available on the BBC's iplayer service after broadcast. |
Year(s) Of Engagement Activity | 2019 |
Description | Business Insider contacted for comment |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | I was contacted by Business Insider to comment on an article related to habitable environments and off-world exploration, and quoted in the resulting article. |
Year(s) Of Engagement Activity | 2019 |
Description | Engagement talk (Local) |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Undergraduate students |
Results and Impact | I gave a talk on the science of 'The Martian' movie from an exoplanet research perspective, linked in with a screening of the film. |
Year(s) Of Engagement Activity | 2019 |
Description | Knowle and Dorridge Astronomy society |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | I gave an invited talk at a local astronomy society meeting, talking about my research and the exoplanet field. |
Year(s) Of Engagement Activity | 2019 |
Description | Press release - Machine learning for exoplanet discovery |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | We made a press release to accompany a publication in Summer 2020 on the discovery of 50 new planets using machine learning. The interest was significant, appearing in 100s of international news outlets. The press release led directly to an invite to be a main keynote speaker at a major industry data science conference (ODSC Europe 2020), and several contacts offering computing time or expertise. |
Year(s) Of Engagement Activity | 2020 |
Description | Press release, radio and TV interview - Remnant planetary core |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | A significant publication was released in Summer 2020, on the discovery of the remnant core of a giant planet. We made a press release along with the publication, which led to hundreds of news outlets featuring the case, including prominent international and US media. I gave a live interview both on BBC World News (TV) and on BBC Radio 4's PM show, a primetime news show. |
Year(s) Of Engagement Activity | 2020 |
Description | The Times quoted on K2-18 publication |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | I was contacted by The Times to comment on a recent exoplanet paper, and quoted in the resulting article. |
Year(s) Of Engagement Activity | 2019 |