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GMACS is being developed for the entire Giant Magellan Telescope community by scientists and engineers at the Center for Astrophysics and at the Steiner Institute in Sao Paulo Brazil.  Scientists and engineers at Texas A&M University led early GMACS design studies.  Dr. Stephen Shectman at the Carnegie Observatories developed the original GMACS concept.


  • GMACS is GMT’s first-light multi-object optical spectrograph

  • Wavelength coverage 3300 to 10000 Å in two channels (3300 - 6600 Å) and (6600 to 10000 Å)

  • Resolution R~1000 to R~6000 with 0.7″ slit width

  • Field of view is 7´ in the spatial axis, up to 6´ in the dispersion axis

  • GMACS operates with a wide field corrector/ADC to minimize slit losses due to atmospheric dispersion and to allow long observations of a selected field.

  •  GMACS accommodates 20 on-board laser-cut slit masks for object selection

  • GMACS will also operate with MANIFEST, GMT’s configurable fiber optic adapter.  The initial MANIFEST field of view is 14´ diameter, eventually 20´.


GMACS Powerpoint Overview