STScI is requesting white papers from the community with compelling scientific ideas for Multi-Cycle Treasury programs that require large allocations of JWST telescope time to complete.

The deadline for white papers is Wednesday, November 4, 2026 at 11:59pm ET via this submission form. 

JWST continues to advance our understanding of the universe as it enters its fifth year of regular science observations. Transformational science, from studies of small objects in the Solar System to large-scale cosmology, is being accomplished by programs using the full range of instrument modes, and a wide range of time allocations, from a few hours to a few hundred hours. Given the ongoing unprecedented data quality and the anticipated excelling capacity of both the telescope and its instruments for years to come, the time is right to explore JWST science that requires time allocations exceeding those allocated to large programs to date.

With this goal in mind, STScI calls on the user community to submit White Papers with ideas for JWST Multi-Cycle Treasury (MCT) programs covering any science topic. The White Papers should describe compelling science ideas that can only be accomplished with amounts of telescope time larger than those typically approved by the regular Time Allocation Committee process (about 300 hundred hours). White papers outlining concerns about the potential establishment of JWST MCT programs may also be submitted.

A summary of JWST’s current capabilities can be found in the Pocket Guide. New modes and instruments updates for Cycle 6 can be found here.

White papers should be limited to no more than 5 pages (11 points font or larger; excluding references) and submitted as a pdf file. Each pdf file should contain a title, list of co-authors, abstract, scientific justification, and estimated observing time required.

White papers received by the deadline of Wednesday, November 4, 2026 will be reviewed by experts from the community, who will evaluate the scientific merit of the submitted concepts and justification of the estimated amount of telescope time. Evaluations will be confidential and will help STScI and the JWST Project Office at NASA’s Goddard Space Flight Center (GSFC) determine if a call for JWST MCT Program proposals is warranted at this time.

While STScI will not publish the white papers, authors are welcome to do so, but should keep in mind STScI's Dual Anonymous Peer Review (DAPR) guidelines that disallow the use of substantial verbatim extracts from previously published materials in future proposals.

Please contact the JWST Help Desk with any questions or issues. Additionally, authors are encouraged to join the Webb Office Hours session held on August 27th at 11am ET, where experts will be available to answer questions related to this call for white papers.