GTO

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 3 GTO Programs

ID	Program Title	Principal Investigator	Instrument/Mode	Allocated Hours
4513	Internal Dynamics of Milky Way Dwarf Spheroidal Galaxies	Roeland van der Marel	NIRCam/Imaging	4.2
4514	Dynamics of the Andromeda Galaxy Satellite System	Roeland van der Marel	NIRCam/Imaging	3.9
4515	Galactic Center Astrometry	Roeland van der Marel	NIRCam/Imaging	3.0
4523	Titan Surface and Atmosphere - JWST Cycle 3 GTO Project	Jonathan Lunine	NIRCam/Imaging	1.5
4524	The Physics of Brown Dwarfs – Part #4	Catarina Alves de Oliveira	NIRSpec/FS	2.3
4526	Spectroscopy of an edge-on protoplanetary disk	Thomas Henning	NIRSpec/IFU	2.0
4527	CANUCS: The CAnadian NIRISS Unbiased Cluster Survey	Chris Willott	NIRSpec/MOS	6.0
4528	Galaxy Assembly with NIRSpec Integral Spectoscopy: Complementary Cycle 3 Observations	Nora Luetzgendorf	NIRSpec/IFU	70.0
4529	MIRI Imaging of Cen A	Daniel Dicken	MIRI/Imaging	2.3
4530	MIRI Studies of Lensed Galaxies at Redshifts Above 9	Luis Colina Robledo	MIRI/Imaging MIRI/MRS NIRSpec/IFU	14.8
4531	HH211 Kinematics	Thomas Ray	NIRCam/Imaging	1.9
4532	Spectroscopy of SBS0335-052	Goeran Oestlin	MIRI/MRS NIRSpec/IFU	6.5
4533	LRS Spectroscopy of a MIRI/ALMA Galaxy	Goeran Oestlin	MIRI/LRS	5.9
4534	Exoplanet search around Altair	Charles Beichman	NIRCam/Coronagraphy	7.0
4535	Follow-up Observations of NIRCAm Sources in the planetary system HR8799	Charles Beichman	NIRCam/Coronagraphy	4.4
4536	Constraining the SO2 Abundance of GJ 3470 b	Thomas Greene	NIRSpec/BOTS	7.3
4537	B335 with NIRSpec IFU	Klaus Hodapp	NIRSpec/IFU	5.0
4538	Exo-Asteroid Belts with JWST: Pinpointing the Warm Dust Emission	Schuyler Wolff	MIRI/Imaging NIRCam/Coronagraphy	13.3
4539	Spectroscopy of T8 WISE 2255-3118	Thomas Roellig	MIRI/LRS NIRSpec/FS	2.5
4540	Deep NIRCam grism observations in the 1210 parallel field	Daniel Eisenstein	NIRCam/WFSS	29.4
4541	Search for Varuna's Satellite	John Stansberry	NIRCam/Imaging	3.2
4542	NIRSpec IFU on free floating analogs	Michael Meyer	NIRSpec/IFU	3.5
4543	Coronagraphic Imaging the Source of the Disk Kinematic Kink around HD 97048	Jarron Leisenring	NIRCam/Coronagraphy	4.5
4545	Brown dwarfs & free-floating planetary mass objects in the Rosette Nebula: imaging	Mark McCaughrean	NIRCam/Imaging	11.4
4547	The stellar & sub-stellar initial mass function in Sharpless 305: imaging	Mark McCaughrean	NIRCam/Imaging	10.3
4548	The intermediate-mass protostellar outflow, HH288	Mark McCaughrean	NIRCam/Imaging	8.0
4549	JWST/NIRCam Slitless Spectroscopy in the JWST/MIRI HUDF Region	George Rieke	NIRCam/WFSS	19.6
4551	MIR Extinction for ice sightlines with measured UV extinction	Karl Gordon	MIRI/MRS	2.3
4552	MSA observations of the MACS J1149.5+2223 field	Massimo Stiavelli	NIRSpec/MOS	13.5
4553	IFU observations of high redshift galaxies	Massimo Stiavelli	NIRSpec/IFU	12.5

Cycle 2 GTO Programs

ID	Program Title	Principal Investigator	Instrument/Mode	Allocated Hours
2757	Understanding the Origin of Boyajian's Star Occultations	Massimo Stiavelli	NIRSpec/FS MIRI/LRS MIRI/Imaging	5.9
2758	NIRSpec MSA Observations of Galaxies in a Parallel Field	Massimo Stiavelli	NIRSpec/MOS	29.2
2759	NIRISS Exploration of the Atmospheric Diversity of Transiting Exoplanets (NEAT)	David Lafreniere	NIRISS/SOSS	10.1
2760	Titan Surface and Atmosphere - JWST Cycle 2 GTO Project	Jonathan Lunine	NIRSpec/IFU MIRI/MRS	13.6
2763	SN 1987A: The Formation and Evolution of Dust in a Supernova Explosion	Margaret Meixner	MIRI/MRS	6.3
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	21.3
2771	Structure, Excitation, and Proper Motions in the Symmetric HH212 Jet: Epoch 2	Mark McCaughrean	NIRCam/Imaging	10.0
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	6.1
2774	The Environment of ULAS J1120+0641	George Rieke	NIRCam/Imaging	8.2
2775	A Census of Star Formation and Early Quenching in a High-z Galaxy Cluster	Stacey Alberts	NIRCam/Imaging	3.7
2778	Imaging Spectroscopy of the Coldest Imaged Exoplanet and a Low-Mass Accreting Protoplanet	Marshall Perrin	NIRSpec/IFU MIRI/MRS	7.2
2780	Coronagraphic Imaging of Scattered light Debris Disks - Cycle 2	Andras Gaspar	NIRCam/Coronagraphy	57.2

Cycle 1 GTO Programs

ID	Program Title	Principal Investigator	Instrument	Allocated Hours
1176	JWST Medium-Deep Fields -- Windhorst IDS GTO Program	Rogier Windhorst	NIRCam/Imaging NIRSpec/IFU	114.8
1177	MIRI Observations of Transiting Exoplanets	Thomas Greene	MIRI/Imaging and LRS	75.7
1178	Ram Pressure Stripping in ESO 137-001	Karl Gordon	MIRI/MRS	15.8
1179	YSO Imaging	Jarron Leisenring	NIRCam/Imaging	19.8
1180	NIRCam-NIRSpec Galaxy Assembly Survey - GOODS-S - Part #1a	Daniel Eisenstein	NIRCam/Imaging NIRSpec/MOS	360.0
1181	NIRCam-NIRSpec Galaxy Assembly Survey - GOODS-N	Daniel Eisenstein	NIRCam/Imaging NIRSpec/MOS	151.5
1182	NIRCam GTO - IRDC Mapping	Erick Young	NIRCam/Imaging	20.6
1183	Coronagraphic Imaging of Scattered light Debris Disks	Andras Gaspar	NIRCam/Coronagraphic Imaging NIRSpec/FS	33.1
1184	A NIRCam Coronagraphic Imaging Survey of Nearby Young M Stars	Joshua Schlieder	NIRCam/Coronagraphic Imaging	32.7
1185	Transit Spectroscopy of Mature Planets	Thomas Greene	NIRCam/GTS NIRSpec/BOTS	155.9
1186	Protostar (YSO) Spectroscopy	Thomas Greene	NIRSpec/IFU	19.4
1187	Extinction Mapping of Pre-stellar Cores	Klaus Hodapp	NIRCam/WFSS	41.8
1188	Spectroscopy of Young, Widely Separated Exoplanets	Klaus Hodapp	MIRI/Imaging and LRS NIRSpec/IFU	22.7
1189	NIRCam Y-Dwarfs	Thomas Roellig	MIRI/Imaging, LRS, and MRS NIRCam/Imaging NIRISS/AMI NIRSpec/IFU and FS	36.0
1190	Embedded Cluster Survey	Michael Meyer	NIRCam/Imaging	12.9
1191	Kuiper Belt Science with JWST	John Stansberry	MIRI/MRS NIRSpec/IFU	29.1
1192	Physics and Chemistry of PDR Fronts	Karl Misselt	MIRI/Imaging and MRS NIRCam/Imaging NIRSpec/IFU	48.0
1193	Coronagraphic Imaging of Young Planets and Debris Disk with NIRCam and MIRI	Charles Beichman	MIRI/Imaging NIRCam/Coronagraphic Imaging	64.3
1194	Characterization of the HR 8799 Planetary System and Planet Search	Charles Beichman	MIRI/Imaging NIRCam/Coronagraphic Imaging	29.9
1195	Coronagraphic Imaging of Young Planets - Part 3	Charles Beichman	NIRCam/Coronagraphic Imaging	4.3
1198	IFU Spectroscopy of the Host Galaxies of Strongly Lensed Quasars	Massimo Stiavelli	NIRCam/Imaging NIRSpec/IFU	22.4
1199	The Metallicity of Galaxies in the MAC J1149.5+2223 Field	Massimo Stiavelli	NIRCam/Imaging NIRSpec/MOS	32.0
1200	Architecture of Directly-imaged Extrasolar Planetary Systems	Thomas Vandal	NIRISS/AMI	8.8
1201	NIRISS Exploration of the Atmospheric Diversity of Transiting Exoplanets (NEAT)	David Lafreniere	NIRISS/SOSS NIRSpec/BOTS	194.9
1202	The NIRISS Survey for Young Brown Dwarfs and Rogue Planets	Aleks Scholz	NIRISS/WFSS	20.2
1204	Are There AGN Embedded in All Ultraluminous Infrared Galaxies (ULIRGs)?	George Rieke	MIRI/MRS NIRSpec/IFU	19.4
1205	Formation Histories and Stellar Masses of Very High-z Quasars	George Rieke	NIRCam/Imaging NIRSpec/IFU	41.0
1206	Extreme Debris Disks and Disk Variability	George Rieke	MIRI/MRS	13.4
1207	MIRI in the Hubble Ultra-Deep Field	George Rieke	MIRI/Imaging NIRSpec/MOS	90.3
1208	CANUCS: The CAnadian NIRISS Unbiased Cluster Survey	Chris Willott	NIRCam/Imaging NIRISS/WFSS NIRSpec/IFU and MOS	218.4
1209	Probing the Cloud Properties of SIMP0136+0933	Etienne Artigau	NIRISS/SOSS	4.3
1210	NIRCam-NIRSpec Galaxy Assembly Survey - GOODS-S - Part #1b	Nora Luetzgendorf	NIRSpec/MOS	73.4
1211	NIRSpec WIDE MOS Survey - GOODS-N	Nora Luetzgendorf	NIRSpec/MOS	30.6
1212	NIRSpec WIDE MOS Survey - GOODS-S	Nora Luetzgendorf	NIRSpec/MOS	28.2
1213	WIDE MOS Survey - AEGIS	Nora Luetzgendorf	NIRSpec/MOS	17.4
1214	NIRSpec WIDE MOS Survey - COSMOS	Nora Luetzgendorf	NIRSpec/MOS	16.8
1215	NIRSpec WIDE MOS Survey - UDS	Nora Luetzgendorf	NIRSpec/IFU and MOS	26.3
1216	Integral Field Spectroscopy in GOODS-S	Nora Luetzgendorf	NIRSpec/IFU	72.2
1217	Integral Field Spectroscopy in COSMOS	Nora Luetzgendorf	NIRSpec/IFU	72.6
1218	NIRSpec-IFU Observations of Two QSOs at z=6	Nora Luetzgendorf	NIRSpec/IFU	6.5
1219	NIRSpec and MIRI spectroscopy of QSOs - part #3	Nora Luetzgendorf	MIRI/MRS NIRSpec/IFU and MOS	18.8
1220	NIRSpec IFS of BR1202 and LBQS0302-0019	Nora Luetzgendorf	NIRSpec/IFU	8.5
1222	Cosmic Re-ionization, Metal Enrichment, and Host Galaxies from Quasar Spectroscopy	Chris Willott	NIRSpec/FS, IFU, and MOS	41.1
1223	NIRSpec GTO observations of NGC 4654	Torsten Boeker	NIRSpec/IFU	2.5
1224	Transiting Exoplanet Characterization with JWST/NIRSPEC	Stephan Birkmann	NIRSpec/BOTS	49.5
1225	Star Formation in the Local Grouroup - NGC 3603	Guido De Marchi	NIRSpec/MOS	3.7
1226	Star Formation in the Local Group - NGC 2070 (30 Dor)	Guido De Marchi	NIRSpec/MOS	5.7
1227	NGC 346: Star Formation at Low Metallicity in the Small Magellanic Cloud	Margaret Meixner	MIRI/Imaging and MRS NIRCam/Imaging NIRSpec/MOS	29.4
1228	The Physics of Brown Dwarfs - Part #1	Catarina Alves de Oliveira	NIRSpec/MOS	2.6
1229	The Physics of Brown Dwarfs - Part #2	Catarina Alves de Oliveira	NIRCam/Imaging NIRSpec/MOS	7.6
1230	The Physics of Brown Dwarfs - Part #3	Catarina Alves de Oliveira	MIRI/MRS NIRCam/Imaging NIRISS/AMI NIRSpec/FS	13.9
1231	Surface Composition of Mid-sized TNOs: Searching for Ammonia	Aurelie Guilbert-Lepoutre	NIRSpec/FS and IFU	8.8
1232	SN 1987A: The Formation and Evolution of Dust in a Supernova Explosion	Gillian Wright	MIRI/Imaging and MRS NIRSpec/IFU	9.6
1233	I Zw 18: Dust Life Cycle at Very Low Metallicity	Margaret Meixner	MIRI/Imaging NIRCam/Imaging	6.5
1234	NGC 6822: Dust Life Cycle Study of a Nearby Low Metallicity Galaxy	Margaret Meixner	MIRI/Imaging NIRCam/Imaging	20.8
1235	LMC-N79: Study of Most Massive Young Stellar Object Star Forming Region	Margaret Meixner	MIRI/Imaging and MRS NIRCam/Imaging	16.9
1236	Protostellar Binaries	Michael Ressler	MIRI/MRS	12.7
1237	Star Formation in the Extreme Outer Galaxy	Michael Ressler	MIRI//Imaging NIRCam/Imaging	8.4
1238	Sparse Spectral Mapping of NGC 1514	Michael Ressler	MIRI/Imaging and MRS	9.9
1239	Investigating Dusty Disks in Evolved Stars	Michael Ressler	MIRI/MRS	8.6
1240	De-mystifying SPRITEs with JWST	Michael Ressler	MIRI/LRS NIRSpec/FS and IFU	6.6
1241	MIRI Coronagraphic Imaging of Exoplanets	Michael Ressler	MIRI/Coronagraphic Imaging	36.7
1242	Planets in Formation and Exozodiacal Disks	Doug Johnstone	NIRISS/AMI	16.5
1243	Exploring the End of Cosmic Reionization	Simon Lilly	NIRCam/Imaging and WFSS	126.5
1244	Large Asteroids and Trojan Asteroids	Andrew Rivkin	MIRI/MRS NIRSpec/IFU	12.5
1245	Near-Earth Objects	Cristina Thomas	MIRI/MRS NIRCam/Imaging NIRSpec/FS	23.4
1246	Jupiter's Great Red Spot	Leigh Fletcher	MIRI/MRS	7.0
1247	Saturn	Leigh Fletcher	MIRI/MRS NIRCam/Imaging NIRSpec/IFU	20.1
1248	Uranus	Leigh Fletcher	MIRI/MRS NIRSpec/IFU	13.0
1249	Neptune	Leigh Fletcher	MIRI/MRS NIRSpec/IFU	9.0
1250	Probing the Sub-surface Oceans of Europa and Enceladus with JWST	Geronimo Villanueva	MIRI/Imaging and MRS NIRCam/Imaging NIRSpec/IFU	10.4
1251	Titan Climate, Composition and Clouds	Conor Nixon	MIRI/MRS NIRCam/Imaging NIRSpec/IFU	15.0
1252	Spectral Mapping of a Comet's Inner Coma	Michael Kelley	MIRI/MRS NIRCam/Imaging NIRSpec/IFU	13.0
1253	ToO Comet	Stefanie Milam	MIRI/MRS NIRSpec/IFU	13.3
1254	TNOs	Alex Parker	MIRI/Imaging and LRS NIRSpec/IFU	15.0
1255	JWST Medium-Deep Fields -- Hammel IDS GTO Program	Stefanie Milam	NIRCam/Imaging	2.3
1256	Brown Dwarfs and Free-floating Planetary Mass Objects in Orion: Imaging	Mark McCaughrean	NIRCam/Imaging	34.9
1257	The Young Protostellar Outflow HH211	Thomas Ray	MIRI/MRS NIRCam/Imaging NIRSpec/IFU	26.8
1258	Structure, Excitation, and Proper Motions in the Symmetric HH212 Jet	Mark McCaughrean	NIRCam/Imaging	9.9
1260	NGC 1068 as Proving Ground for NIRISS AMI	K. E. Saavik Ford	NIRISS/AMI	5.3
1262	Integral Field Spectroscopy at z > 8	Nora Luetzgendorf	MIRI/Imaging and MRS NIRSpec/IFU	38.0
1263	NIRSpec and MIRI Spectroscopy of QSOs - Part 2	Luis Colina Robledo	MIRI/MRS NIRSpec/IFU	10.1
1264	NIRSpec and MIRI IFS of SMGs	Luis Colina Robledo	MIRI/Imaging and MRS NIRSpec/IFU	39.9
1265	NGC 6240	Almudena Alonso-Herrero	MIRI/MRS NIRSpec/IFU	6.3
1266	NIRSpec & MIRI Integral-Field Spectroscopy of the Galactic Center	Macarena Garcia Marin	MIRI/MRS NIRSpec/IFU	9.4
1267	NIRSpec+MIRI IFU Observations of Arp220	Daniel Dicken	MIRI/MRS NIRSpec/IFU	8.0
1268	NIRSpec & MIRI Integral-Field Spectroscopy of the Nucleus of Mrk 231	Roberto Maiolino	MIRI/MRS NIRSpec/IFU	6.9
1269	NIRSpec Observations of Centaurus-A: A GTO Program Proposal	Nora Luetzgendorf	MIRI/MRS NIRSpec/IFU	6.3
1270	Characterizing the TWA 27 System	Stephan Birkmann	MIRI/Imaging and MRS NIRSpec/IFU	8.7
1271	ToO TNOs: 'Unveiling the Kuiper Belt by Stellar Occultations'	Pablo Santos-Sanz	NIRCam/Imaging	2.3
1272	Kuiper Belt Science with JWST	Dean Hines	MIRI/Imaging and MRS NIRSpec/IFU	17.8
1273	Kuiper Belt Science with JWST	Jonathan Lunine	MIRI/Imaging and LRS NIRSpec/IFU	18.0
1274	Extrasolar Planet Science with JWST	Jonathan Lunine	MIRI/LRS NIRCam/GTS	75.1
1275	Spectroscopic Characterization of PSO J318	Pierre-Olivier Lagage	MIRI/Imaging and MRS NIRSpec/IFU	4.2
1276	Spectroscopic Observations of WD 0806-661B	Pierre-Olivier Lagage	MIRI/Imaging and LRS NIRCam/Imaging NIRSpec/IFU	11.0
1277	Coronographic Observations of Young Exoplanets and Spectroscopic Observations of ROSS 458 C	Pierre-Olivier Lagage	MIRI/Coronagraphic Imaging, LRS, and MRS NIRSpec/IFU	24.7
1278	MIRI Spectroscopic Observations of Brown Dwarfs	Pierre-Olivier Lagage	MIRI/MRS	6.2
1279	Thermal Emission from Trappist1-b	Pierre-Olivier Lagage	MIRI/Imaging	26.7
1280	MIRI Transiting Observation of WASP-107b	Pierre-Olivier Lagage	MIRI/LRS	10.9
1281	MIRI and NIRSPEC Transit Observations of HAT-P-12 b	Pierre-Olivier Lagage	MIRI/LRS NIRISS/SOSS NIRSpec/BOTS	32.7
1282	MIRI EC Protoplanetary and Debris Disks Survey	Thomas Henning	MIRI/MRS and Coronagraphic Imaging NIRCam/Imaging NIRSpec/IFU	135.4
1283	The MIRI HUDF Deep Imaging Survey	Goeran Oestlin	MIRI/Imaging	63.9
1284	MIRI IFS of COSMOS sources COS-zs7-1 and B14-65666	Luis Colina Robledo	MIRI/Imaging and MRS	19.1
1286	NIRCam-NIRSpec Galaxy Assembly Survey - GOODS-S - Part #2	Nora Luetzgendorf	NIRSpec/MOS	148.6
1287	NIRCam-NIRSpec Galaxy Assembly Survey - GOODS-S - Part #3	Nora Luetzgendorf	NIRSpec/MOS	73.8
1290	MIRI EC Protostars Survey	Ewine Van Dishoeck	MIRI/MRS NIRSpec/IFU	44.0
1292	ROSS 458 ABc	Jonathan Lunine	NIRSpec/FS	8.6
1293	Collimation Zone in Protostellar Jets, the Final Frontier. MIRI MRS and Imager Simultaneous Observations	Alberto Noriega-Crespo	MIRI/Imaging and MRS	11.4
1294	Thermal Emission Spectroscopy of Beta Pictoris' Prototypical Debris Disk	Christine Chen	MIRI/MRS	14.1
1304	Internal Dynamics of Milky Way Dwarf Spheroidal Galaxies	Roeland van der Marel	NIRCam/Imaging	4.8
1305	Dynamics of the Andromeda Galaxy Satellite System	Roeland van der Marel	NIRCam/Imaging	5.5
1306	Galactic Center Astrometry	Roeland van der Marel	NIRCam/Imaging	1.5
1312	Transit and Eclipse Spectroscopy of a Warm Neptune	Nikole Lewis	MIRI/LRS NIRISS/SOSS NIRSpec/BOTS	34.6
1331	Transit Spectroscopy of TRAPPIST-1e	Nikole Lewis	NIRSpec/BOTS	22.6
1353	Transit and Eclipse Spectroscopy of a Hot Jupiter	Nikole Lewis	MIRI/LRS NIRISS/SOSS NIRSpec/BOTS	75.6
1411	Coronagraphy of the Debris Disk Archetype Beta Pictoris	Christopher Stark	MIRI/Coronagraphic Imaging NIRCam/Coronagraphic Imaging	25.3
1412	Characterizing 51 Eridani Exoplanetary System	Marshall Perrin	NIRCam/Coronagraphic Imaging	14.5
1413	MIRI Coronagraphy of the Cold Substellar Companion GJ 758 B	Laurent Pueyo	MIRI/Coronagraphic Imaging	11.4
1414	Integral Field Spectroscopy of the Benchmark Substellar Companion HD 19467 B	Marshall Perrin	NIRSpec/IFU	6.7
1415	Mars Observations: GTO Program	Geronimo Villanueva	NIRCam/Imaging NIRSpec/FS	7.0

Abbreviations:

BOTS = Bright Object Time-series

FS = Fixed Slit

GTS = Grism Time Series

IFU = Integral Field Unit

LRS = Low Resolution Spectroscopy

MOS = Multi-object Spectroscopy

MRS = Medium Resolution Spectroscopy

SOSS = Single-object Slitless Spectroscopy

TSO = Time Series Observation

WFSS = Wide Field Slitless Spectroscopy

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Guaranteed Time Observation Programs

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Cycle 2

Cycle 3 GTO Programs

Cycle 2 GTO Programs

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