About this Article

Amaya Moro-Martín (amaya[at]stsci.edu) and Alexandra Hamanowicz (ahamanowicz[at]stsci.edu) for the JWST Science Policy Division

Published April 21, 2026

The James Webb Space Telescope (JWST) Cycle 5 Science Program, scheduled to begin July 1, 2026, encompasses approximately 8,000 hours of prime observations, which will continue to enable groundbreaking work across all areas of astrophysics. 

Proposal Submission

The Cycle 5 Call for Proposals was released August 1, 2025, with a deadline of October 15, 2025. A deadline extension was provided to proposers unable to undertake research during the partial U.S. government shutdown, and those facing extenuating and unforeseen circumstances. 

The worldwide astronomical community engaged in an unprecedented brainstorm, submitting 2,930 proposals and setting a new record for proposals received in response to any Call for Proposals by a major observatory. The JWST Telescope Allocation Committee (TAC) met February 1 to 11, 2026 to review the submissions. 

Summary of Compliant Proposal Statistics

75 proposals were disqualified for page limit, formatting, policy, or anonymity violations (see the appendix). The 2,855 compliant proposals included:

• 2,568 General Observer (GO) proposals requesting 99,782 hours (an oversubscription of around 1:12 by hours), including 43 Treasury proposals and 14 Pure Parallel proposals;
• 52 Survey proposals; and
• 231 Archival Research (AR) proposals (107 Regular, 20 Legacy, and 104 Theory).

Of these proposals, 49 were submitted in response to the new Long-Term Monitoring Initiative, and 33 in response to the new Roman Preparatory Science Initiative.

The proposals involved 7,363 unique investigators from 849 unique institutions in 57 countries. The detailed submission and acceptance statistics are on the JSTUC webpage toward the top, titled: Summary of the Results from the JWST Cycle 5 TAC.

Proposal Selection Planning

The Telescope Allocation Committee (TAC) comprised two Executive Committee (EC) Chairs, 34 panel Chairs and Vice Chairs, one At-Large Member, 191 Discussion panelists divided across 18 Discussion panels, and 322 External panelists divided across eight External panels. The TAC members have a broad swath of scientific expertise, were well-distributed geographically, represented multiple career stages, and were drawn from a wide range of institution types.

GO Proposals are classified as Very Small (≤ 20 hours), Small (> 20 and ≤ 50 hours), Medium (> 50 and ≤ 130 hours), and Large (> 130 hours) with respect to total charged time, including overheads. Very Small GO proposals and Regular AR proposals were sent for review by the External panels. Small and Medium GO proposals and all Target of Opportunity (ToO) and Survey proposals, regardless of size, are sent for review by the Discussion panels. The Galactic and Extragalactic Executive Committees are in charge of reviewing the Large GO, Treasury, Legacy AR, and the Pure Parallel proposals.

Of the 2,855 compliant proposals, 395 were moved to a different Scientific Category than that originally identified by the proposers to ensure the best matches between proposal keywords and reviewers’ expertise. Proposals are assigned for review considering reviewers’ expertise, conflicts of interest, and workload.

Peer-Review Process

All documents and orientation materials related to the review process are publicly available on the JWST Peer Review Guide in JDox. Proposals sent to the External panels are reviewed asynchronously. After the final reviews and grades were submitted, these proposals are ranked and the top ranked proposals recommended for approval.

Proposals sent to the Discussion panels and ECs are reviewed in two phases: an initial preliminary grading phase followed by a meeting to discuss and regrade the top-ranked 30 to 35% of proposals based on the preliminary scores. The 18 Discussion panels met virtually for four days during the week of February 2, 2025. The two ECs (Galactic and Extragalactic) met in person at STScI on February 9 and 10 and February 11 and 12, respectively. During this phase, Discussion and EC panels discussed proposals and graded them after each discussion, assessed the final ranking of proposals for science balance, and addressed science duplications within the panel. Discussion panels also provided feedback to their Chairs and Vice Chairs on a subset of Large, Treasury, Legacy, and Pure Parallel proposals to support the ECs deliberations.

The most important outcome of the TAC meeting is the ranked lists. Each panel received an initial hour allocation (N) proportional to the time requested by the GO proposals that submitted to that panel. Panelists were asked to carefully rank top proposals to twice that hour allocation (2N). The final rankings include consideration of the overall science balance and the Chairs’ and Vice Chairs’ recommendations on how to adjudicate science and observation duplications. 

Science duplications are identified by the TAC when the scientific outcomes of different programs are very similar and could overlap or be redundant. They are not prohibited by policy, but the TAC may consider them an inefficient use of JWST time, leading to the rejection of one of the proposals. Observation duplications are observations of the same target or field using the same instrument, same mode, same optical elements and with an exposure time within about a factor of four. They are only allowed if there is a clear scientific justification and are adjudicated following the TAC recommendations.  

We’d like to express a heartfelt thank you to all the JWST reviewers who showed an extraordinary commitment to the successful completion of the proposal peer-review process, resulting in the Cycle 5 Science Program described below.

Cycle 5 Science Program

The STScI Director is the Selecting Official for JWST. The recommendations from the Cycle 5 TAC were presented to the STScI Director for endorsement on March 5, 2026. The results were announced to the community on March 13, 2026.

Summary of Requested and Approved Proposal Statistics

Accepted JWST Cycle 5 Proposals by Size

Of the 254 accepted proposals, 227 are GO proposals for a total of 8,009 prime hours. These include three Treasury, two Calibration GO (52.6 hours), nine Joint JWST-HST, one Joint JWST- XMM-HST, four Long-Term Monitoring Initiative, four Roman Preparatory Science Initiative (305 hours), and seven ToO with one Disruptive and 31 Non-Disruptive activations. 

Twenty-four proposals have been accepted for Archival Research, including 13 Regular, eight Theory, three Legacy, of which one is Long-Term Monitoring Initiative, two Roman Preparatory Science Initiative (305 hours), and two Data Science Software. The Cycle 5 Science Program also includes three Surveys (536 targets), and one Pure Parallel (1,000 hours). 

The accepted proposals span all major instrument observing modes. The fractions of prime (prime plus coordinated) hours by instrument are: 

• MIRI 25.1% (24.8%), 
• NIRCam 13.3% (18.2%), 
• NIRISS 6.9% (7.1%), and
• NIRSpec 54.7% (49.6%): 20% (27%) is imaging and 80% (73%) is spectroscopy. 

Instrument Usage by Time

The Cycle 5 Science Program includes 2,275 hours of observations (28% of the total available) that have zero Exclusive Access Period and will be made available to the community immediately upon release to the Barbara A. Mikulski Archive for Space Telescopes (MAST). This set includes the programs recommended by the Galactic and Extragalactic Executive Committees, summarized in the article JWST Cycle 5 Science Highlights.

Information about the approved proposals is available on the Cycle 5 GO page. The accepted proposals span the full range of science anticipated for JWST. A full summary of the approved proposals statistics is posted on the JSTUC webpage under Summary of the Results from the JWST Cycle 5 TAC.
 

Accepted Cycle 5 Proposals by Scientific Category

An Increasingly Broad JWST User Community

The 254 accepted proposals involve 2,333 unique investigators at institutions worldwide from 37 countries, 44 U.S. states plus Washington, D.C., seven Canadian Provinces and Territories, and 18 European Space Agency (ESA) countries. There are 153 PIs and 86 co-PIs from the U.S., 69 PIs and 62 Co-PIs from ESA countries, and 10 PIs and 10 Co-PIs from the Canadian Space Agency (CSA). The statistics indicate a continued success at reaching an increasingly broad community, with a remarkable 46% of PIs being first-time JWST PIs (111 of 240 unique PIs).

What’s Next for Cycle 5 Accepted Proposals

All JWST observing proposals recommended by the TAC are subject to technical review before they are accepted for execution and become JWST programs. The technical review may identify changes to the implementation to optimize the observations. Recommended proposals are also checked for duplications against observations in previous cycles. Repeat observations that are justified scientifically are approved for execution.

Cycle 5 verification and duplication checking have already started. Cycle 5 will start July 1, 2026, and end June 30, 2027, but some Cycle 5 observations will be scheduled beyond Cycle 5 boundaries because of visibility windows and to maximize JWST observing efficiency. Likewise, about 20% of the time available between July 1, 2026, and June 30, 2027 (corresponding to the Cycle 5 boundaries) will be used to execute observations from previous cycles.

Grant Allocation for Cycle 5 will use the formula-based approach introduced in Cycle 4. The budget submission deadline is April 30, 2026 at 5 p.m. Eastern. All submitted budgets will be subject to review of allowability, scope, and reasonableness by the Financial Review Committee, which is composed of members of the community and STScI.

Cycle 6

The high oversubscription rate implies that many excellent proposals well-liked by the reviewers could not be selected in Cycle 5. Another opportunity will soon open. The JWST Cycle 6 Call for Proposals is scheduled to be released on Monday, July 20, 2026, with a deadline of Wednesday, September 30, 2026, at 8 p.m. Eastern.

Proposers should take care to follow the policy and guidelines in the Call for Proposals. The appendix below describes the compliance violations found in Cycle 5. This information is included here to guide future proposers on how to craft compliant proposals.

Serve on the TACs

STScI runs two TACs each year, one for JWST (typically from November to February) and one for HST (typically from April to July). These peer-review processes are one of the most important community activities STScI undertakes during the year. Given the unpreceded response to the JWST Call for Proposals, STScI will continue to recruit an increasing number of community members to serve as reviewers in future Cycles. Most reviewers reflect that their participation is rewarding and find it to be a learning opportunity.

STScI cannot run the proposal selection without the expertise and support of many community members. We highly value the time and energy our reviewers commit year after year. It is thanks to their dedication and professionalism that the review process is considered a gold-standard by many community members and stakeholders. Please consider volunteering and accepting the invitation to serve. Postdocs with at least two years of experience and those more senior are eligible, but in exceptional cases more junior researchers may be considered.

Volunteer to Serve on Users Committees

Another way to get involved is through the JWST Users Committee (JSTUC). The JSTUC is responsible for advising STScI and the JWST Project on all aspects of observatory operations. This provides a practical way of ensuring that the observatory operations proceed in a coordinated manner to maximize the telescope’s scientific performance. The next JSTUC meeting is in early May 2026.

You can volunteer to serve on the JSTUC if your institution is located in a NASA, ESA, and/or CSA country. Membership lasts three years. The committee meets twice a year, typically in the spring and fall, with additional communications as warranted. Several members rotate off after every meeting, approximately every six months, so we are always in search of new JSTUC members.

Self-nomination is very welcome. Submissions are encouraged to include a short cover letter summarizing the nominee’s relevant background and JWST-related interests, along with a curriculum vitae. Submitted these materials to jstuc-nominations@stsci.edu. Nominations will be considered on a rolling basis.

There is an equivalent Hubble Space Telescope Users Committee (STUC) whose members are drawn from NASA and ESA countries. Nominations may be submitted to stuc-nominations@stsci.edu. The next Hubble STUC meeting is in late April 2026.

Appendix: Proposal Compliance

Proposers are recommended to submit early and resubmit often to ensure the most updated version of the proposal is received before the system closes at 8 p.m. Eastern on the deadline. Six proposals were automatically rejected for having been submitted after the deadline, and 40 proposals with late resubmission were reverted to their last version before the deadline.

Reviewers brought to STScI attention 183 proposals with possible compliance violations. Upon careful consideration, this resulted in 75 recommendations for disqualifications that were brought to the Director’s Office for approval (this constitutes 2.6% of the submitted proposals, a percentage that is similar to previous cycles). Disqualified proposals were removed from the review. A further 54 proposals (1.8%) were issued warnings; these were reviewed but future issues of the same nature risk disqualification. The remaining 54 proposals reported were found to be compliant and no action was taken.

The reasons for disqualifications and warnings included dual anonymous violations; font, margin, and/or template changes; page limits violations; selection of wrong proposal type; lack of justification of special requirements; issues related to the use of Generative Artificial Intelligence (AI); attachment of the wrong PDF; and multiple in-cycle submissions. We highlight a few of these below in more detail:

Template and Formatting Changes, Including Fonts and Margins

Unaltered templates are enforced to guarantee a level field for all proposers and readability for reviewers. Proposers should not make changes to the templates. Proposers should also take care when importing additional packages in the LaTeX templates as these can inadvertently change aspects of the formatting.

Dual Anonymity Peer Review (DAPR)

The goal of DAPR is to remove the focus of the proposal from the proposing team and place it on the proposed science. Anonymity is a tool used to reach that goal, not the end goal itself. Accordingly, proposals should not disclose the identity of the proposing team, nor should they discuss the team, even anonymously. Submitted proposals should not include claims of ownership for work carried out by the proposing team, including publications and previous accepted proposals. They should not include extensive quotes of text from publications or previously approved programs, and they should not disclose membership in collaborations. Further, they should not reference team composition or team expertise, including identifying a program as a student thesis project.

Special Requirements

All Special Requirements need to be justified scientifically in the PDF, included in the APT file, and identified appropriately using the corresponding fields in the APT Proposal Information form. If they are not, they might not be met. See JWST Observation Planning Essentials for key items often forgotten. Proposers should also make sure the right Proposal Type is selected to ensure that the correct APT options are offered and avoid being sent to the wrong panel, which could lead to disqualification.

Generative Artificial Intelligence (AI)

Proposers should be thoughtful about the use of generative AI. The JWST proposal selection process is not a lottery where the more proposals submitted the higher the chances of getting approved. Anecdotally, the PIs with the largest numbers of submitted proposals in Cycle 5 did not have any proposal accepted. Multiple in-cycle submissions are strictly prohibited (e.g., almost identical proposals, which leads to the disqualification of all proposals involved). Proposers should focus on their best ideas, because only the highest quality proposals have a chance. The Call for Proposals states that the use of generative AI must be declared but some uses of AI are not acceptable, like those resulting in hallucinated references to support the science case. Proposers should check the Call for Proposals for updates on generative AI policy.

Acknowledgements

STScI is extremely grateful to everyone involved in the many stages and tasks related to the proposal selection process. Every cycle we receive numerous comments from reviewers, Chairs, and NASA, ESA and CSA officials who greatly appreciated the professionalism shown by all reviewers and STScI staff. A heartfelt thank you to the two Executive Committee Chairs, Dr. Mark Wyatt and Dr. Xiaohui Fan, the 35 members of the Executive Committees, the 191 Discussion panelists, and the 322 External panelists. It is thanks to their generous support, expertise and commitment that STScI was able to continue implementing a thorough peer-review selection process despite the unpreceded high number of proposal submissions. JWST proposal reviewers play a critical role in maximizing the science return of the mission.

In addition, numerous STScI personnel supported the review at its different stages. The overall coordination was led by TAC Manager and JWST Science Policy Lead Amaya Moro-Martín, Science Policy Division Head Laura Watkins, Cross-Mission Policy Scientist Molly Peeples, and Technical Manager Aleksandra Hamanowicz. Meeting logistics were led by Sherita Hanna. Others involved in making the process a success were:

• Director’s Office: Nancy Levenson, Mercedes López-Morales, Jennifer Lotz, Rachel Osten, Neill Reid
• Science Policy Division: Amber Armstrong, Brett Blacker, Aleksandra Hamanowicz, Amy Jones, Nimisha Kumari, Rebecca Levy, Joshua Lothringer, Amaya Moro-Martín, Nikolay Nikolov, Molly Peeples, David Stark, Linda Smith, Lou Strolger, Laura Watkins
• Event Support (EPG and ESA): Melody Easton, Sherita Hanna, Marleen Palacios Calderon, Victory Ramnarine, Jean-Baptiste Regnard (ESA), Shemiah Smith-Ramos
• APT: Gary Curtis, Andrew Myers, Mike Oboryshko, Karla Peterson
• Instruments and Telescope Support: Marta Boyer, Alicia Canipe, Aarynn Carter, Mike Engesser, Dave Golimowski, Paul Goudfrooij, Bryan Hilbert, Diane Karakla, David Law, Katherine Murray, Alberto Noriega-Crespo, Patrick Ogle, Brian O'Sullivan, Kate Rowlands, Jo Taylor, Deepashri Thatte, Kevin Volk
• Observers (JWST Mission Office): Stacey Bright, Tom Brown, Macarena Garcia-Marin, Marshall Perrin, Marco Sirianni, Jeff Valenti
• Observers (CSA): Jean Dupuis
• Observers (ESA): Chris Evans, Paule Sonnentrucker
• Observers (NASA): Knicole Colon, Hannah Jang-Condell, Michael McElwain, Stefanie Millan, Susan Neff, Jane Rigby, Amber Straughn
• Office of Public Outreach: Andi James
• Panel Support Staff: Alejandro Crespo Gomez, Matthew Dalas, Archene Dyrek, Federico Fogantini, Ilias Goovaerts, Santosh Harish, Farhanul Hasan, Calum Hawcroft, Mans Holmbert, Jegug Ih, Logan Jones, Avery Kim, Alexander Madurowicz, Mariarosa Marinelli, Pierluigi Rinaldi, Tony Roman, Jimena Rodriguez, Melissa Sahbandeh, Sachindev Shenoy, Alison Vick, Ian Wong, Brian York
• Scheduling: Beth Perriello, Tony Roman
• Tech Support: Gary Gilbert, Kevin Flinn, Rob Gontrum and the ITSD team
• WASABI Support: Matej Bludsky, Jeff Bucklew, Aasif Chanandin, Alex Framerini, Craig Hollinshead, Lauretta Nagel, Doug Paul
• Copy Center: Zak Concannon
• Facilities: Raven Baxter, Brad Bukowsky, Andre DeShazo, Bermond Few, Rob Franklin, Tiffany Lallo, Trevor Thompson, Richard Washington, Mike Venturella, Gee Williams
• Housekeeping/Custodial Staff: Carrie Harris, William White
• Catering: Carma’s Catering and the Mt. Washington Tavern

Thank you all!