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Dr Subhajit Sarkar

Dr Subhajit Sarkar

Astronomy Group
Astronomy Instrumentation Group
Cardiff Hub for Astrophysics Research and Technology

School of Physics and Astronomy

+44 (0)29 2087 0116
N/0.05, Queen's Buildings - North Building, 5 The Parade, Newport Road, Cardiff, CF24 3AA
Available for postgraduate supervision


I’m a Lecturer and astrophysicist working in the field of extra-solar planets.  I am involved in the development of new missions and observatories to characterise the atmospheres of exoplanets, in particular the ESA Ariel mission, as well as Twinkle and the NASA EXCITE mission. I also am involved in cycle 1 JWST exoplanet observations in collaboration with IoA Cambridge. I am interested in understanding atmospheric and planetary processes in temperate regime sub-Neptunes and gas giants, and how these relate to fundamental questions of planet formation and the diversity of the exoplanet population.  I am also interested in astrobiology, particularly the potential for biospheres in temperate gas giants, modeling of observations to find the frequency of life-bearing worlds (the fL factor in the Drake Equation), and how exoplanetary observations might be able to constrain theories of the origin of life.



  • PhD, Astrophysics, Cardiff University
  • MSc (Distinction), Space Science, University College London
  • Diploma in Physics (Distinction), Open University
  • MA, Natural Sciences, Cambridge University
  • MB, BChir, Medicine, Cambridge University
  • Grad. Cert. Applied Sciences, Space Studies, University of South Australia
  • Space Studies Program, International Space University

Professional memberships

  • Fellow of the Royal Astronomical Society
  • Fellow of the Higher Education Academy

Academic positions

  • 2022- Present: Lecturer, School of Physics and Astronomy, Cardiff University
  • 2017-2021: Post-doctoral Research Associate, Cardiff University
  • 2013-2017: Post-graduate Research Student, Cardiff University
  • 2003-2005: Visiting Researcher, Space Medicine & Health Care Systems Office, NASA Johnson Space Center, Houston.
  • 2003-2005: Honorary Lecturer in Space Life Sciences, Dept. of Space & Climate Physics, University College London


  • BBC Radio Wales Science Cafe interview about the ARIEL space mission (April 2018).
  • Pythagorean Astronomy podcast interview about TESS, ARIEL and other exoplanet missions (April 2018).
  • Exoplanet talks for Cardiff AS Level Summer Programmes 2018/19.
  • Stargazing talk and telescope observing with Scouts (Spring 2019).
  • Online astronomy talk with Scouts (Winter 2020).
  • 'All About Space' magazine interview about Ariel mission ('Rise of the Exoplanet Hunter') (Jan 2021).
  • Twinkle mission YouTube video ('The Founding Members') (Aug 2021).
  • Pythagorean Astronomy podcast interview about JWST observing programme (Dec 2021).
  • Cardiff School of Physics & Astronomy YouTube video about JWST (Dec 2021).














Current undergraduate teaching

  • PX1127 Planet Earth: Module Organiser
  • PX2140 Stars and Planets : cover planets section of module

Previous undergraduate teaching

  • PX1127 Planet Earth: Deputy Module Organiser
  • PX2134 Structured Programming: Lab supervisor
  • PX1125 Mathematical Practice for Physical Sciences: Marker
  • PX1222 Mathematical Methods for Physicists 2: Marker


  • I supervise PhD and MPhys research projects (see supervision page)

Research focus

  • Development of new exoplanet observatories and missions:
    • Ariel: Ariel Data Reduction Pipeline (ADaRP) development lead, simulations working group lead, spectral retrievals working group, ground segment and calibration working groups.
    • EXCITE: first dedicated phase-curve spectroscopy observatory; first balloon-borne exoplanet observatory; official NASA collaborator
    • Software developed: ExoSim, ExoSim_N, JexoSim (JWST simulator), TwinkleSim, ADaRP
  • Exoplanet atmospheres
    • JWST: Co-I on Cycle 1 GO program 2722:
      'Chemical Disequilibrium in a Temperate sub-Neptune'. Approx. 20 hours. We will use NIRISS, NIRSpec and MIRI to obtain the transmission spectrum of the sub-Neptune K2-18 b from 0.6 to 12 microns.
    • Temperate gas giants: (with Luke Booth) developing modeling and observational approaches to characterise this poorly-understood exoplanet population.
    • Twinkle mission: science team member and designated observer for Cardiff, cool gas giant working group. I will be shaping the observation programme of the Twinkle exoplanet atmospheric survey.
  • Astrobiology
    • DRAKE (Dedicated Research for Advancing Knowledge of Exobiology): a proposed space mission to find the frequency of life in the Galaxy using transit spectroscopy (paper accepted for MNRAS).
    • Aerial biospheres in temperate gas giants: modeling these in preparation for future observations.


Current supervision

  • I am primary PhD supervisor for Luke Booth who is researching exoplanet atmospheres.
  • I am currently on the supervisory team as mentor for two PhD students.
  • I currently supervise two undergraduate projects titled 'Water in exoplanets'.

Past projects

  • I have previously co-supervised several MPhys and MSc projects:
    • Signal and noise simulations for exoplanet observations by the Twinkle instrument
    • Simulations of star spots and faculae and their impact on exoplanet transmission spectra
    • Designing a telescope to characterise Earth-like planet atmospheres