Johannes Sahlmann


Main Research Fields

My main research interests are the observational study of the transition region between giant extrasolar planets and brown dwarfs (objects not massive enough to ignite hydrogen fusion), in particular their discovery and characterisation using a variety of techniques and instruments. I specialised in high-precision astrometry, that is the measurement of stellar positions in the sky plane, obtained with instruments on the ground and in space.


  • Extrasolar planets
  • Brown dwarfs
  • Binary stars
  • Astrometry
  • Astronomical instrumentation

Ongoing collaborations

Incomplete list of scientific collaborators

  • A. Burgasser (UC San Diego, USA)
  • D. Bardalez Gagliuffi (American Museum of Natural History, USA)
  • D. Ségransan, B. Holl (Geneva, Switzerland)
  • D. Queloz (Cambridge, UK)
  • E. L. Martin (IAC, Spain)
  • G. Hébrard (Sorbonne, France)
  • M. R. Zapatero Osorio (CAB Madrid, Spain)
  • P. Lazorenko (Kyiv, Ukraine)
  • T. Dupuy (Gemini, USA)
  • ​and many others


on ADS

Project/mission at ESA

  • Gaia

Research homepage