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Dr Craig Agnor


Senior Lecturer in Astronomy

Telephone: 020 7882 3464
Room Number: G. O. Jones Building, Room 505


My teaching for this year includes:

  • SPA5241 Planetary Systems (Term A)
  • SPA6776 Extended Independent Project
  • SPA6913 Physics Review Project
  • SPA7016 Physics Research Project
  • I have also written the module MTH6110 Communicating and Teaching Mathematics that is offered through the School of Mathematical Sciences.


Research Interests:

The overarching goal of my research is to understand the origin of planets and satellites.  More specifically, I am interested in how gravitational dynamics determine the orbital structure of planetary systems and how giant collisions may account for the development of particular planetary characteristics (e.g. large obliquities, satellite formation, thermal excess/deficits).  In this work I utilize a combination of analytic theory and numerical simulation (e.g., N-body orbital integrations, hydrodynamic calculations of planetary collisions) to examine the collisional and dynamical evolution of planets.

In the past my work has addressed a variety of topics in solar system evolution including:

  • The formation of the terrestrial planets and the origin of the Earth/Moon system.
  • The capture of Neptune's large retrograde moon Triton.
  • `Giant Impacts' between planets and the origin of planetary characteristics.
  • Understanding the implications of large-scale orbital migration of the solar system's giant planets.



The EChO science case
Tinetti G, Drossart P, Eccleston P et al.
EXPERIMENTAL ASTRONOMY, Volume 40, issue 2-3, page 329, 1st December 2015.
DOI: 10.1007/s10686-015-9484-8

Embryo impacts and gas giant mergers - II. Diversity of hot Jupiters' internal structure
Liu S-F, Agnor CB, Lin DNC et al.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Volume 446, issue 2, page 1685, 11th January 2015.
DOI: 10.1093/mnras/stu2205


Neptune and triton: Essential pieces of the solar system puzzle
Masters A, Achilleos N, Agnor CB et al.
Planetary and Space Science, Volume 104, issue PA, page 108, 1st January 2014.
DOI: 10.1016/j.pss.2014.05.008

The science case for an orbital mission to Uranus: Exploring the origins and evolution of ice giant planets
Arridge CS, Achilleos N, Agarwal J et al.
Planetary and Space Science, Volume 104, issue PA, page 122, 1st January 2014.
DOI: 10.1016/j.pss.2014.08.009


Neptune and Triton: Essential pieces of the Solar System puzzle
Masters A, Achilleos N, Agnor CB et al.
Planetary and Space Science, 13th December 2013.
DOI: 10.1016/j.pss.2014.05.008

Possible scenarios for eccentricity evolution in the extrasolar planetary system HD 181433
Campanella G, Nelson RP, Agnor CB
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Volume 433, issue 4, page 3190, 1st August 2013.
DOI: 10.1093/mnras/stt959


Tinetti G, Beaulieu JP, Henning T et al.
EXPERIMENTAL ASTRONOMY, Volume 34, issue 2, page 311, 1st October 2012.
DOI: 10.1007/s10686-012-9303-4

Uranus Pathfinder: exploring the origins and evolution of Ice Giant planets
Arridge CS, Agnor CB, Andre N et al.
EXPERIMENTAL ASTRONOMY, Volume 33, issue 2-3, page 753, 1st April 2012.
DOI: 10.1007/s10686-011-9251-4

Agnor CB, Lin DNC
ASTROPHYSICAL JOURNAL, Volume 745, issue 2, 1st February 2012.
DOI: 10.1088/0004-637X/745/2/143


The science of EChO
Tinetti G, Cho JYK, Griffith CA et al.
Proceedings of the International Astronomical Union, Volume 6, page 359, 1st January 2011.
DOI: 10.1017/S1743921311020448


Li SL, Agnor CB, Lin DNC
ASTROPHYS J, Volume 720, issue 2, page 1161, 10th September 2010.
DOI: 10.1088/0004-637X/720/2/1161

Beurle K, Murray CD, Williams GA et al.
ASTROPHYS J LETT, Volume 718, issue 2, page L176, 1st August 2010.
DOI: 10.1088/2041-8205/718/2/L176

Three-body capture of irregular satellites: Application to Jupiter
Philpott CM, Hamilton DP, Agnor CB
ICARUS, Volume 208, issue 2, page 824, 1st August 2010.
DOI: 10.1016/j.icarus.2010.03.026


Dynamical and thermal implications of Martian core formation timescales
Nimmo F, Agnor CB
GEOCHIMICA ET COSMOCHIMICA ACTA, Volume 72, issue 12, page A684, 1st July 2008.

Implications of an impact origin for the martian hemispheric dichotomy.
Nimmo F, Hart SD, Korycansky DG et al.
Nature, Volume 453, issue 7199, page 1220, 26th June 2008.
DOI: 10.1038/nature07025


Meteoritical and planetological consequences of "hit and run" non-accretionary giant impacts
Asphaug E, Agnor CB, Scott ERD et al.
METEORITICS & PLANETARY SCIENCE, Volume 41, issue 8, page A18, 1st August 2006.

Neptune's capture of its moon Triton in a binary-planet gravitational encounter
Agnor CB, Hamilton DP
NATURE, Volume 441, issue 7090, page 192, 11th May 2006.
DOI: 10.1038/nature04792

Isotopic outcomes of N-body accretion simulations: Constraints on equilibration processes during large impacts from HfAV observations
Nimmo F, Agnor CB
EARTH PLANET SC LETT, Volume 243, issue 1-2, page 26, 15th March 2006.
DOI: 10.1016/j.epsl.2005.12.009

Hit-and-run planetary collisions
Asphaug E, Agnor CB, Williams Q
NATURE, Volume 439, issue 7073, page 155, 12th January 2006.
DOI: 10.1038/nature04311


Accretion efficiency during planetary collisions
Agnor C, Asphaug E
ASTROPHYS J, Volume 613, issue 2, page L157, 1st October 2004.
DOI: 10.1086/425158


The Role of Giant Planets in Terrestrial Planet Formation
AGNOR CB, Levison HF
Astronomical Journal, Volume 125, page 2692, 1st May 2003.
DOI: 10.1086/374625


Damping of terrestrial-planet eccentricities by density-wave interactions with a remnant gas disk
Agnor CB, Ward WR
ASTROPHYS J, Volume 567, issue 1, page 579, 1st March 2002.
DOI: 10.1086/338415


On the accretion of distant planets
Ward WR, Agnor CB, Tanaka H
ASTROPHYSICAL AGES AND TIME SCALES, Volume 245, page 111, 1st January 2001.

PhD Supervision

This is not an exhaustive list and I would be happy to discuss other project possibilities.

Project Title

Giant Planet Migration in the Solar System

Recent observations of star-forming regions in the Galatic Center have revealed the presence of prebiotic molecular species such as glycolaldehyde, the simplest sugar, or formamide, a precursor of amino acids. Amino acids are key ingredients in the synthesis of proteins and therefore they are considered as the building blocks of life. Glycine is the simplest amino acid and, although it has been reported in meteorites and in comet 67P/Churyumov-Gerasimenko by the Rosetta mission, its detection in the interstellar medium (ISM) remains elusive.

In this project, the student will analyse observations of the rotational molecular emission obtained toward a sample of Giant Molecular Clouds (GMCs) in the Galactic Center to characterise the chemistry of these complex organic molecules in space. Sub-/millimetre data from international facilities such as the IRAM 30m single-dish telescope, the Submillimeter Array (SMA) and the Atacama Large Millimetre Array (ALMA), will be used. The goal of the project will be to constrain the dominant formation/destruction processes of glycine in the ISM to determine the likelihood of detection in the Galactic Center GMCs with future instrumentation such as the Band 1 of ALMA and the Square Kilometre Array (SKA). For full details click here

Collisional Evolution of Planets and Satellites

Giant impacts (i.e., collisions between like-sized objects) are a ubiquitous feature of planet and satellite formation. Our previous work in this area has illustrated that for dynamical environments, typical of late stage terrestrial planet formation, a variety of impact outcomes are plausible ranging from the production of impact-generated satellites to catastrophic disruption. This work has been expanded to consider global collisions of giant planets, terrestrial planets, and planetary satellites. In all such cases, colliding bodies are geophysically processed on a global scale in a variety of unique ways. The universality of large-scale giant impacts renders them a principal evolutionary process for all types of planets, planetary satellites and ring systems.

The principal goal of this programme is to examine how giant impacts process material and determine diversity of planetary and satellite characteristics that have collisional origins. This effort involves coupling the context of giant impacts (e.g., planetary formation, planet migration, satellite evolution) to the outcomes of individual collisions and the collision histories of evolving worlds. The project will focus on a single class of objects (e.g. giant planets, terrestrial planets, planetary satellites). This work will involve using state-of-the-art numerical modeling of individual giant impacts (e.g. using Smoothed Particle Hydrodynamics or N-body gravity codes) and modelling their collisional and orbital evolution. For full details click here

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