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Guaranteed Time Observation Programs

The JWST Guaranteed Time Observations (GTO) program is designed to reward scientists who helped develop the key hardware and software components or technical and inter-disciplinary knowledge for the observatory. The program provides a total of about 16% use of the observatory over the first 3 cycles of operation.

  • Archival Research

    Programs with this icon have components that have no exclusive access period, and can be used as a basis for GO Archival  Research (AR) Proposals.

Cycle 2 GTO Programs

ID Program Title Principal Investigator AR? Instrument/Mode Allocated Hours

Understanding the Origin of Boyajian's Star Occultations

Massimo Stiavelli

Icon denoting JWST Program with no exclusive access period

2758 NIRSpec MSA Observations of Galaxies in a Parallel Field Massimo Stiavelli   NIRSpec/MOS 30.0
2759 NIRISS Exploration of the Atmospheric Diversity of Transiting Exoplanets (NEAT) David Lafreniere   NIRISS/SOSS 10.0
2760 Titan Surface and Atmosphere - JWST Cycle 2 GTO Project Jonathan Lunine   NIRSpec/IFU
2763 SN 1987A: The Formation and Evolution of Dust in a Supernova Explosion Margaret Meixner   MIRI/MRS 6.0
2768 Uranus High Spatial Resolution Global Map from NIRCam Naomi Rowe-Gurney   NIRCam/Imaging 4.4
2770 Brown Dwarfs and Free-floating Planetary Mass Objects in Orion: Spectroscopy Mark McCaughrean   NIRSpec/MOS 20.0
2771 Structure, Excitation, and Proper Motions in the Symmetric HH212 Jet: Epoch 2 Mark McCaughrean   TBD 7.0
2772 Galactic Center Astrometry Roeland van der Marel   NIRCam/Imaging 1.6
2773 Deciphering the Extended Dust and Gas Environment of the Archetypal Type-1 AGN in NGC 4151 with JWST Jianwei Lyu   MIRI/MRS 5.9
2774 The Environment of ULAS J1120+0641 George Rieke   NIRCam/Imaging 8.1
2775 A Census of Star Formation and Early Quenching in a High-z Galaxy Cluster Stacey Alberts   NIRCam/Imaging 3.5
2778 Imaging Spectroscopy of the Coldest Imaged Exoplanet and a Low-Mass Accreting Protoplanet Marshall Perrin   NIRSpec/IFU
2780 Coronagraphic Imaging of Scattered light Debris Disks - Cycle 2 Andras Gaspar   NIRCam/Coronagraphy 28.0


Cycle 1 GTO Programs

The approved GTO programs in Cycle 1 are organized by science topic. To view details about a specific program, select a science category below, then click the Program ID.

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