December 2013 Phobos flyby

At the end of this year, there will be a Phobos flyby by the spacecraft Mars Express. The flyby will allow us to get information on the interior of Phobos. As shown in our 3D animation at on “This animation shows MarsExpress flyby of the moon Phobos of Mars and the influence of the interior of Phobos on the flyby trajectory.“, the flyby trajectory depends on the interior mass repartition. The spacecraft Mars Express has already performed some flybys and the next close flyby will further improve the results concerning the mass of Phobos and its moments of inertia. The study of moment of inertia and mass together with the knowledge of the volume of Phobos allows to get information on the interior density and mass repartition, and there with on Phobos’ origin.

ESA will soon re-activate their own blog where recent information will be found:

ESA websites of interest:

  1. Martian moons: Phobos, posted on the web on
  2. Mars-facing side of Phobos, taken from a distance of less than 200 km with a resolution of about seven meters per pixel, on 22 August 2004, on
  3. Close-up of Phobos acquired on 28 July 2008 by HRC on MarsExpress, on
  4. The Martian moons Phobos and Deimos, ESA’s Mars Express orbiter imaged the Martian moons Phobos and Deimos together on 5 November 2009, on
  5. Simulation of the Phobos flyby of 7 March 2010 showing the relative orbits of Phobos and Deimos and the Mars Express spacecraft, on
  6. Pioneering images of bot Martian moons, ESA’s Mars Express orbiter imaged the Martian moons Phobos and Deimos together on 5 November 2009, on
  7. Mars Express closest ever approach to Phobos on 3 March 2010, see
  8. Images from the flyby of Phobos on 7 March 2010, released on 15 Mar 2010, see and

Further information can be found in:

  1. Lainey V., Dehant V., and Pätzold M., 2007, “First numerical ephemerides of the two Martian moons.”, Astron. Astrophys., 465(3), pp. 1075-1084, DOI: 10.1051/0004-6361:20065466.
  2. Rosenblatt P., Lainey V., Le Maistre S., Marty J.C., Dehant V., Pätzold M., Van Hoolst T., Häusler B., 2008, “Accurate Mars Express orbit to improve the determination of the mass and ephemeris of the Martian moons.”, Planet. Space Sci., 56(7), pp. 1043-1053, DOI: 10.1016/j.pss.2008.02.004.
  3. Andert T.P., Rosenblatt P., Pätzold M., Häusler B., Dehant V., Tyler G.L., and Marty J.C., 2010, “Precise Mass Determination and the Nature of Phobos.”, Geophys. Res. Lett., 37, CiteID: L09202, DOI: 10.1029/2009GL041829.
  4. Rosenblatt P., 2011, “The origin of the Martian moons revisited.”, Astron. Astrophys. Rev., 19(1), pp. 1-26, DOI: 10.1007/s00159-011-0044-6.
  5. Rambaux N., Castillo-Rogez J., Le Maistre S., and Rosenblatt P., 2012, “Rotational motion of Phobos.”, Astronomy & Astrophysics, 548, id.A14, 11 pp., DOI: 10.1051/0004-6361/201219710.
  6. Rosenblatt P., and Charnoz S., 2012, “On the Formation of the Martian Moons from a circum-martian accretion disk.”, Icarus, 221(2), pp. 806-815, DOI: 10.1016/j.icarus.2012.09.009.
  7. Witasse O., Duxbury T., Chicarro A., Altobelli N., Andert T., Aronica A., Barabash S., Bertaux J.-L., Bibring J.-P., Cardesin-Moinelo A., Cichetti A., Companys V., Dehant V., Denis M., Formisano V., Futaana Y., Giuranna M., Gondet B., Heather D., Hoffmann H., Holmström M., Martin P., Matz K.-D., Montmessin F., Morley T., Mueller M., Manaud N., Neukum G., Oberst J., Orosei R., Pätzold M., Picardi G., Pischel R., Plaut J.J., Reberac A., Pardo Voss P., Roatsch T., Rosenblatt P., Remus S., Schmedemann N., Willner K., and Zegers T., 2013, “Mars Express Investigations of Phobos and Deimos.”, ESA publication, submitted.
  8. Le Maistre S., Rosenblatt P., Rambaux N, Castillo-Rogez J.C., Dehant V, and Marty J.C., 2013, “Phobos interior from librations determination using Doppler and star tracker measurements.”, Planetary and Space Science, submitted.
  9. Pätzold M., Andert T., Jacobson R., Rosenblatt P., and Dehant V., 2013, “Phobos: Observed bulk properties.”, Planetary and Space Science, submitted.

Leave a Reply