Hi !

Welcome to my personal page

I am currently a post-doc at the Space Telescope Science Institute (STScI, Baltimore, Maryland, US) in the Extrasolar Planetary Systems Imaging Group (EPSIG).

My research interest lies both in the development of innovative instruments for imaging circumstellar environments (planets or dust) and in the analysis of high contrast images.

Johan Mazoyer
Astrophysics, Aerospace
Post Doc
Space Telescope Science Institute
jmazoyer at stsci dot edu
3700 San Martin Dr., Baltimore, MD 21218

Research positions (PDF)

Since 2014

Space Telescope Science Institute Baltimore, MD, US

Post-doctoral position

  • Active Correction of Aperture Discontinuities for high-contrast imaging
  • Analyze of coronagraphic data of circumstellar disks (NICI, GPI, NICMOS, SPHERE)

  • 2011 - 2014

    Paris Observatory Meudon, France

    PhD Student

  • High-contrast for direct imaging of exoplanets and circumstellar disks: from the self-coherent camera to NICI data analysis
  • Teaching at Paris 7 and Paris 5

  • 2011

    Observatory Midi-Pyrénées Toulouse, France

    Graduate Student

  • Chemcam/Curiosity: Influence of the surrounding atmosphere on the performance

  • Los Alamos National Laboratory Los Alamos, NM, US

    Graduate Student

  • Chemcam/Curiosity: Improvement of the detection limits for atomic and molecular abundances

  • 2010

    CNES Toulouse, France

    Undergraduate Student

  • Power system of a Pleiades satellite: simulation of flight components

  • Education (PDF)

    2011 - 2014

    Université Paris Diderot
    Paris, France

    Ph.D. Astronomy and Astrophysics

    2010 - 2011

    Observatoire Midi-Pyrénées
    Toulouse, France

    M.Sc. Astronomy and Astrophysics

    2010 - 2011

    Toulouse, France

    M.Sc. Space Systems and Space Imaging Techniques

    2007 - 2011

    Ecole Polytechnique
    Palaiseau, France

    B.Sc. Embedded Computer Systems

    • Designing tomorrow's
      astronomical instruments

      The main difficulties of direct imaging are the high contrast level and high angular resolution required to discriminate the planet signal from the stellar light. The flux ratio between a Jupiter-like planet and a Sun-like star is typically 106. For a terrestrial planet, this ratio is about 1010. The angular separation between a planet and the star is typically of a few 0.1 arc-seconds. My research is about designing instruments to make this type of observations a reality.

      On the left image, a region of high contrast (or dark hole), obtained on the optical bench of the Paris Observatory.

    • Deep inside
      circumstellar disks

      The analysis of complex structures in circumstellar disks have already lead to the forecasting of planets. Using the data from ground and space based instruments, I am taking part in this analysis.

      On the left, image of the dust ring around the star HD 15115 using NICI, an instrument of the ground based telescope GEMINI South.

    • Running

      Paris marathon 2013, with my lucky hat.

    • Hiking

      Pierra Menta, French Alps, 2014.

    • Volunteering

      Le Relais, Burkina-Faso, Summer 2009

      This NGO, linked to Emmaüs France, is collecting used clothes in France and ship them in several African countries. I worked for this NGO during the summer 2009, in Koudougou, Burkina Faso

    • Volunteering

      La Main à la Pâte, Perpignan, 2007-2008

      I spent one year as a full time primary school science teacher as a member of La Main à la Pâte. This foundation aims to develop inquiry-based science in primary schools and was launched in 1996 by the physicist Yves Quéré, the astrophysicist Pierre Léna and the Nobel prize winner Georges Charpak, with the support of the French Académie des sciences. Teaching 20 classes a week, my requirements also involved the training of primary school teachers.

    • Podcast Science

      Podcast Science is a french speaking popular science podcast. Behind the scene every week, I have also presented several astrophysics and astronomy episodes.

      Each episode is aired in live every Tuesday (8.30pm France time) and then released as a podcast (Soundcloud, Itunes and Youtube) and in written form.

    Publications (complete list)

    Refereed publications (1st author)

    1. Mazoyer et al. (2016) A symmetric inner cavity in the HD 141569A transitional disk. ApJ 818:150 • PDF

    2. Mazoyer et al. (2015) Active compensation of aperture discontinuities for WFIRST-AFTA: analytical and numerical comparison of propagation methods and preliminary results with a WFIRST-AFTA-like pupil. J. Astron. Telesc. Instrum. Syst. 2(1), 011008 • PDF

    3. Mazoyer et al. (2014) Is the HD 15115 disk really asymmetrical? A&A 569, A29 • PDF

    4. Mazoyer, Ph.D. Thesis (2014) High-contrast direct imaging of exoplanets and circumstellar disks: from the self-coherent camera to NICI data analysis. Université Paris Diderot • PDF

    5. Mazoyer et al. (2014) High-contrast imaging in polychromatic light with the self-coherent camera. A&A 564, L1 • PDF

    6. Mazoyer et al. (2013) Estimation and correction of wavefront aberrations using the self-coherent camera: laboratory results. A&A 557, 9 • PDF

    SPIE papers (1st author)

    1. Mazoyer, et al. (2015) Active Correction of Aperture Discontinuities (ACAD) for space telescope pupils: a parametric analysis Proceedings of the SPIE, 960521 (13pp) • PDF

    2. Mazoyer, et al. (2014) Deformable mirror interferometric analysis for the direct imagery of exoplanets Proceedings of the SPIE, 914846 (11pp) • PDF

    3. Mazoyer, et al. (2013) Speckle correction in polychromatic light with the self-coherent camera for the direct detection of exoplanets Proceedings of the SPIE, 88640N (9pp) • PDF

    4. Mazoyer, et al. (2012) Experimental parametric study of the self-coherent camera Proceedings of the SPIE, 844250 (10pp) • PDF



  • Active correction of aperture discontinuities for high contrast imaging: parametrical analysis, SPIE, San Diego, US (August 2015)
  • Deep inside circumstellar disks: high-contrast instrumental techniques and archival data analysis, STScI wine and cheese seminar, Baltimore, US (April 2015)
  • Deep inside circumstellar disks: high contrast instrumental techniques and data analysis using NICI, LAM optical group seminar (invited), Marseille, FR (Mars 2015)
  • Deep inside circumstellar disks with the GEMINI/NICI coronagraphic instrument, STScI science coffee seminar, Baltimore, US (February 2015)

  • 2014

  • THD bench : description and latest results, Workshop "Combining Coronagraphs and Wavefront Control", Leiden, NL (October 2014)
  • Haut contraste pour l'imagerie directe d'exoplanètes et de disques : de la self-coherent camera à l'analyse de données NICI, PhD defense, Paris, FR (September 2014)
  • Is the HD 15115 circumstellar disk really asymmetrical ? Resolving the inner ring around HD 15115 with NICI., poster, 30 year of β-Pic Conference, Paris, FR (September 2014)

  • 2013

  • La Self Coherent Camera : un instrument pour la détection d'exoplaneètes en imagerie directe, Elbereth Conference, Paris, FR (December 2013)
  • Analyse d'un miroir déformable pour l'imagerie directe d'exoplanètes, Optique Paris 2013, Villetaneuse, FR (October 2013)
  • Self Coherent Camera and THD bench, CNES optical group seminar (invited), Toulouse, France (October 2013)
  • La Self-Coherent Camera : imagerie directe par coronographie pour la détection et l'analyse spectrale d'exoplanètes, Journées des jeunes chercheurs du CNES (awarded best presentation), Toulouse, France (October 2013)
  • Self Coherent Camera and THD bench, Astrium optical group seminar (invited), Toulouse, France (October 2013)
  • Speckles correction in monochromatic light with the self-coherent camera, SPIE, San Diego, US (August 2013)
  • The self-coherent camera: speckle nulling in polychromatic light for the direct detection of exoplanets, LESIA high-angular resolution group seminar (invited), Meudon, FR (August 2013)
  • Direct detection of exoplanets in polychromatic light with a Self-coherent camera, poster, AO4ELT Conference, Firenze, IT (June 2013)

  • 2012 and before

  • A new instrument for the direct detection and analysis of exoplanets, Elbereth Conference, Paris, FR (December 2012)
  • La Self-Coherent Camera : estimation de front d'onde en plan focal pour la détection d'exoplanètes en imagerie directe, Journées recherche et industrie de l'optique adaptative, Marseille, FR (November 2012)
  • Principle of the self-coherent camera, Workshop 'Banc THD', Meudon, FR (October 2012)
  • Experimental parametric study of the self-coherent camera, poster, SPIE, Amsterdam, NL (June 2012)
  • Direct imaging of exoplanets using self-coherent camera, Elbereth Conference, Paris, FR (December 2011)
  • Improvement of the chemcam detection limits for atomic and molecular abundances, Los Alamos National Laboratory, NM (July 2011)

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