| Reed, Sophie | The search for the highest redshift quasars using the Dark Energy Survey | 2017 | University of Cambridge | GMOS-S | UK |
| Reiter, Megan Ruth | Measuring the Physical Properties of Protostellar Outflows from Intermediate-Mass Stars in Feedback-Dominated Regions | 2015 | The University of Arizona | GeMS+GSAOI | USA |
| Rembold, Sandro Barboza | Propriedades dinâmicas e populacionais do aglomerado de galáxias LCDCS S001 | 2007 | Federal University of Rio Grande do Sul | GMOS-S | Brazil |
| Ren, Bin | Detection and Characterization of Circumstellar Disks in Scattered Light | 2019 | The Johns Hopkins University | GPI | USA |
| Reynaldi, Maria Victoria | Interaccion entre los radio-jets y el material interestelar en radiogalaxias | 2014 | Universidad Nacional de La Plata (UNLP) | GMOS-N | Argentina |
| Ricci, Tiago V. | Analyzis of the nuclear and circumnuclear gas emission of a sample of 10 elliptical and lenticular galaxies | 2013 | University of Sao Paulo | GMOS-S | Brazil |
| Riffel, Rogemar A. | Mapeamentotridimensional" do entorno dos buracos negros supermassivos em galáxias Seyfert | 2008 | Federal University of Rio Grande do Sul | NIFS+ALTAIR/GNIRS | Brazil |
| Roe, Henry G. | Titan's atmosphere at high-resolution | 2002 | University of California, Berkeley | Hokupaa | USA |
| Rogerson, Jesse Aaron | Monitoring Broad Absorption-Line Quasar Variability | 2016 | York University (Canada) | GMOS-N/GMOS-S | Canada |
| Rosa, Deise Aparecida | Interactions effects on galaxy pairs with Gemini/GMOS | 2015 | Universidade do Vale do Paraiba | GMOS-S | Brazil |
| Rose, Marvin | On the nature of the red, 2MASS-selected AGN in the local Universe | 2012 | University of Sheffield | GMOS-S | UK |
| Rotermund, Kaja M. | Exploring Infrared-Bright Sources Detected by the South Pole Telescope - Lensing Galaxies and the Most Massive Structures in the Universe | 2020 | Dalhouse University | GMOS-S/FLAMINGOS-2 | Canada |
| Saker, Leila | Material circunestelar en estrellas de tipo enanas blancas | 2020 | Universidad Nacional de Córdoba | GMOS-N/GMOS-S | Argentina |
| Sales, Dinalva Aires de | Propriedades físicas dos silicatos e hidrocarbonetos aromáticos policíclicos presentes na região nuclear das galáxias Seyferts e Starburst | 2012 | Federal University of Rio Grande do Sul | MICHELLE/TRECS | Brazil |
| Salinas, Ricardo | Dark matter in central and isolated galaxies | 2011 | Universidad de Concepcion | GMOS-S | Chile |
| Sanders, Nathan Edward | Core-collapse Supernova Progenitors in the Era of Untargeted Transient Searches | 2014 | Harvard University | GMOS-N | USA |
| Sanmartim, David | População estelar e cinemática de quasares post | 2013 | Federal University of Rio Grande do Sul | GMOS-N/GMOS-S | Brazil |
| Saracino, Sara | A Multi-Conjugate Adaptive Optics view of Bulge Globular Clusters | 2018 | University of Bologna | GSAOI+GeMS | Other |
| Scarano, Sérgio | Rotation Curves and Metallicity Gradients of Spiral Galaxies: The Role of the Corotation Radius and New Observations | 2008 | University of Sao Paulo | GMOS-N | Brazil |
| Schaefer, Gail Helen | Dynamical masses of pre-main sequence stars | 2004 | State University of New York at Stony Brook | NIRI+ALTAIR | USA |
