Earthshine from Armagh (believe it or not...)

Contact Details

Research Interests

On the theoretical front, I am interested in the characteristics and stability of co-orbital motion (1:1 mean motion resonance) in the Solar System, both now and in the past. In collaboration with Drs. Fathi Namouni (SWRI, Boulder, CO) and Prof. Carl Murray (QMUL) we have demonstrated the existence and dynamical robustness of hitherto unknown modes of co-orbital motion, which appear only at high eccentricities and inclinations.

I have been investigating the possibility of observing meteors in the atmosphere of Mars as a means of extending our knowledge of the meteoroid complex in the mm to dm size range. These kinds of observations may be carried out by simple instruments aboard landers or from orbit.

Research on the irregular satellites of the gas giants has picked up recently due to numerous new discoveries . I have been looking at the effect of gravitational scattering in families and found that, in some cases, these may have been observably scattered by the largest family member.

The uranian satellite mutual events are almost upon us. See here for details.

Fun stuff

Visit the Martian Astronomy site.

My astrophotography escapades.

The art of Astrodynamics: a short primer on how to go from A to B in the Solar System

Publications in Planetary Science

Refereed Journals

• HIDAS, M. G., CHRISTOU, A. A., BROWN, T. M., 2008, An observation of a mutual event between two satellites of Uranus, Mon. Not. Royal Astron. Soc. 384, L38--L40.
• CHRISTOU, A. A., NAMOUNI, F., MOREIRA MORAIS, M. H., 2007, The long term stability of coorbital moons of the satellites of Saturn I. Conservative case, Icarus 192, 106--116.
• CHRISTOU, A. A., VAUBAILLON, J., WITHERS, P., 2007, The dust trail complex of comet 79P/du Toit-Hartley and meteor outbursts at Mars, Astron. Astrophys. 471, 321--329.
• VAUBAILLON, J., CHRISTOU, A. A., 2006, Encounters of the dust trails of comet 45P/Honda-Mrkos-Pajdusakova with Venus in 2006, Astron. Astrophys. 451, L5--L8.
• MCAULIFFE, J. P., CHRISTOU, A. A., 2006, Modelling meteor ablation in the venusian atmosphere, Icarus 180, 8--22.
• CHRISTOU, A. A., 2005, Mutual events of the uranian satellites 2006-2010, Icarus 178, 171--178.
• CHRISTOU, A. A., 2005, Gravitational scattering with the Himalia group of jovian prograde irregular satellites, Icarus 174, 215--229.
• CHRISTOU, A. A., 2004, Prospects for meteor shower activity on the venusian atmosphere, Icarus 168, 23--33.
• PATEL, M. R., CHRISTOU, A. A., COCKELL, C. S., RINGROSE, T. J., ZARNECKI, J. C. 2004, The UV environment of the Beagle 2 landing site: detailed investigations and detection of atmospheric state, Icarus 168, 93--115.
• DUNKIN S. K. and 48 authors, 2003, Scientific rationale for the D-CIXS X-ray spectrometer on board ESA's SMART-1 mission to the Moon, Plan. Space Sci. 51 , 435--442.
• GRANDE, M. and 47 authors., 2003, The D-CIXS X-ray mapping spectrometer on SMART-1, Plan. Space Sci. 51, 427--433.
• CHRISTOU, A. A., 2003, The statistics of flight opportunities to accessible near-Earth asteroids, Plan. Space Sci. 51, 221--231.
• CHRISTOU, A. A., 2002, Lander position determination on Mars using Phobos transits: application to Beagle 2, Plan. Space Sci. 50, 781--788.
• CHRISTOU, A. A., 2000, Co-orbital objects in the main asteroid belt, Astron. Astrophys. 356, L71--L74.
• CHRISTOU, A. A., 2000, A numerical survey of transient co-orbitals of the terrestrial planets, Icarus 144, 1--20.
  
• CHRISTOU, A. A., BEURLE, K., 1999, Meteoroid streams at Mars: possibilities and implications, Plan. Space Sci. 47, 1475--1485.
• NAMOUNI, F., CHRISTOU, A. A., and MURRAY, C. D., 1999, Co-orbital dynamics at large eccentricity and inclination, Physical Review Letters 83, 2506-2509.
• CHRISTOU, A. A., MURRAY, C.D., 1999, The effect of near resonances on the secular precession of close orbits, Mon. Not. Royal Astron. Soc. 303, 806--812.
• CHRISTOU, A.~A., MURRAY, C.~D., 1997, A second order Laplace--Lagrange theory applied to the uranian satellite system, Astron. Astrophys. 327, 416--427.

Conference Contributions

• CHRISTOU, A. A., 2004, Meteor showers at the nearest planets: prospects and opportunities. In Meteoroids 2004 , London, Ontario, Canada, Aug 16-20, 2004.
• CHRISTOU, A. A., 2004, The gravitational stirring of the irregular prograde satellites of Jupiter, Abstract #09.04. In 35th Annual Meeting of the Division of Dynamical Astronomy of the American Astronomical Society , Cannes, France, Apr 20-23, 2004.
• CHRISTOU, A. A., 2004, The dynamical stirring of the irregular prograde satellites of Jupiter. In Joint Astronomical Science Group of Ireland/Institute of Physics Meeting, Armagh, Northern Ireland, Apr 1-4, 2004.
• CHRISTOU, A. A., 2003, From Mercury to Mars: Present and future of terrestrial planet exploration, keynote talk, Session 43: Exploring the terrestrial planets. In NAM 2003 , Dublin, Republic of Ireland, April 7-11, 2003.
• CHRISTOU, A. A., 2003, The nearest of near-Earth asteroids, Abstract 45.4. In NAM 2003 , Dublin, Republic of Ireland, April 7-11, 2003.
• CHRISTOU, A. A., 2002, The statistics of flight opportunities to near-Earth asteroids, Abstract #2.17. In Asteroids, Comets, Meteors 2002 , Berlin, Germany, July 29-August 2, 2002.
• CHRISTOU, A. A., 2001, The Trojans of Ceres and Vesta, Abstract #52.05. In 33rd Annual Meeting of the Division for Planetary Sciences of the American Astronomical Society , New Orleans, Lousiana, USA, October 27-December 1, 2001.
• CHRISTOU, A. A., 2001, Ceres:a true minor planet. In CERES 2001 workshop on astrometry and physics of minor planets from observational networks , Paris, France, October 9-12, 2001.
• CHRISTOU, A. A., PALMER, P. L., HASHIDA, Y., 2001, Application of symplectic filters for high-precision orbit estimation of small satellites, Paper #5258. In 2001 AIAA Guidance, Navigation & Control Conference , Montreal, Canada, August 6-9, 2001.
• DUNKIN, S. K., GRANDE, M., HEATHER, D. J., ALLEYNE, H., CASANOVA, I., CLARK, P. E., CHRISTOU, A., FERNANDES, V. A., FOING, B. H., HUOVENIN, J., KAUKKANEN, J., RUSSELL, S. S., KELLETT, B. J., SWINYARD, B., VILHU, O., 2000, The D-CIXS X-ray spectrometer on ESA's SMART-1 mission to the Moon: Science objectives, Abstract #1648. In 31st Lunar and Planetary Science Conference , Houston, Texas, March 13-17, 2000.
• CHRISTOU, A. A., 1999, Dynamics of temporary co-orbital asteroids of the Earth and Venus, Abstract #28.08. In 31st Annual Meeting of the Division for Planetary Sciences of the American Astronomical Society , Padova, Italy, October 10-15, 1999.
• NAMOUNI, F., CHRISTOU, A. A., MURRAY, C. D, 1999, New coorbital dynamics in the solar system, Abstract #6.03. In Asteroids, Comets, Meteors 1999 , Ithaca, NY, July 26-30, 1999.
• CHRISTOU, A. A., 1999, {The behaviour of secular frequencies near mean motion resonances}. In {\it Proceedings of the IAU Colloquium 172: ``Impact of Modern Dynamics in Astronomy''} (Henrard, J. and Ferraz-Mello, S., Eds.), Kluwer Academic Publishers, 1999, p427--428.\\
• CHRISTOU, A.~A., 1999, Applications of a high order secular perturbation theory: the Uranian satellites and beyond. In Proceedings of the NATO Advanced Study Institute on ``The dynamics of small bodies in the solar system: A major key to solar system studies'' (Steves, B. A. and Roy, A. E., Eds.), Kluwer Academic Publishers, 1999, p289--294.
• CHRISTOU, A. A., 1999, Future planetary missions. In Proceedings of the NATO Advanced Study Institute on ``The dynamics of small bodies in the solar system: A major key to solar system studies'' (Steves, B. A. and Roy, A. E., Eds.), Kluwer Academic Publishers, 1999, p587--593.
• CHRISTOU, A. A., BEURLE, K., 1999, Opportunities for meteor science at Mars, Abstract #184. In International Symposium on Mars Exploration and Sample Return Missions , Paris, France, Feb.~1--5, 1999.
• CHRISTOU, A.~A., MURRAY, C.D., 1998, Analytical modelling of the uranian satellite system. In Proceedings of the IXth Rencontres de Blois on ``Planetary Systems: The Long View'' (Celnikier, L.~M.~and Tran Thanh Van, J., Eds.), Editions Frontieres, 1998, p167--169.