JWST Cycle 2 Guaranteed Time Observations Call for Proposals

James Webb Space Telescope (JWST) Guaranteed Time Observations (GTO) are awarded to scientists selected under AO 01-OSS-05 and through NASA-ESA-CSA agreements. GTOs with remaining allocations may submit GTO programs for Cycle 2.

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We invite JWST Guaranteed Time Observers (GTOs) to submit Cycle 2 GTO science proposals. NASA policy requires that GTO Cycle 2 science proposals, including targets and observation specifications, be submitted by 2 months prior to the JWST Cycle 2 General Observer (GO) Call for Proposals. GTO targets and observing specifications will be ingested into the STScI archive and released to the community prior to the Cycle 2 GO Call for Proposals.

Proposing calendar and deadlines

Cycle 1 dates: June 25, 2022 to June 30, 2023

Cycle 2 GTO proposal deadline: September 14, 2022

Cycle 2 Call for Proposals: November 15, 2022

Cycle 2 dates: July 1, 2023 - June 30, 2024

GTO proposal submission

Teams should submit revised proposals using the Astronomer's Proposal Tool (APT). APT 2022.5 will be released as part of PPS 14.19 on July 28, 2022. Proposals should be completed by September 14, 2022. APT 2022.5 does not include the final timing model that will be used for Cycle 2, so GTO proposers will not be held to strict time limits. GTOs will have an opportunity to adjust and finalize their proposals prior to the Cycle 2 GO deadline.

Who's responsible

Members of the Science Mission Office at STScI are responsible for the oversight of the JWST science program selection process. The members involved include Neill Reid (Associate Director for Science), Alessandra Aloisi (Head, Science Mission Office), Christine Chen, Katey Alatalo, Amaya Moro-Martin, and Technical Manager Brett Blacker.

Where to get help

Submit questions to the JWST helpdesk at jwsthelp.stsci.edu.  Consult JWST documentation at jwst-docs.stsci.edu, and see stsci.edu/jwst for additional tools and resources. 

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