The primary purpose of the Director's Discretionary Early Release Science (DD ERS) program is to educate and inform the community regarding JWST's capabilities, and provide rapid access to substantive, representative datasets to enable full scientific exploitation in Cycle 2 and beyond. The rationale, goals, and organizing principles of the DD ERS program are described. Approved JWST Director's Discretionary Early Release Science (DD ERS) programs are required to provide project updates to the astronomy community and undergo status reviews by STScI.


With its 6.5m mirror and suite of four science instruments, JWST will provide imaging, spectroscopic and coronagraphic capabilities from 0.6 to 28.5 microns, offering an unprecedented combination of sensitivity and spatial resolution to study objects from the Solar System to the most distant galaxies.  Realizing JWST’s full science potential requires that the scientific community rapidly learns to use its sophisticated capabilities. To that end, STScI, in consultation with the JWST Advisory Committee, has developed the Director’s Discretionary Early Release Science (DD ERS) program.

Goals and Principles

The overall goals of the DD ERS program are to:

  • ensure open access to representative datasets in support of the preparation of Cycle 2 proposals, and

  • engage a broad cross-section of the astronomical community in familiarizing themselves with JWST data and scientific capabilities.

These goals distinguish the DD ERS program from standard GO investigations. In service of these goals, DD ERS proposals are invited from the community.

The DD ERS program is guided by the following key principles:

  • Projects must be substantive science demonstration programs that utilize key instrument modes to provide representative scientific datasets of broad interest to researchers in major astrophysical sub-disciplines. Note that a meritorious DD ERS project need not cover every mode of the observatory. The request should match the focused science goals of the proposal.

  • Projects must design, create, and deliver science-enabling products to help the community understand JWST's capabilities.  An initial set of products must be delivered by the release of the Cycle 2 GO Call for Proposals (7 months after the start of science observations in Cycle 1 or ~13 months after launch).  Each project must define a core team to be responsible for the timely delivery of such products according to a proposed project management plan, with performance subject to periodic review.

  • All observations must be schedulable within the first 5 months of Cycle 1  and a substantive subset of the observations must be schedulable within the first three months.   Target lists must be flexible to accommodate possible changes to the scheduled start of science observations.

  • Both raw and pipeline-processed data will enter the public domain immediately after processing and validation at STScI. These data will have no exclusive access periods (i.e., no proprietary time).

  • STScI recognizes and supports the benefits of having diverse and inclusive scientific teams involved in the formulation of ERS proposals.  Programs with diverse representation of community members in a given sub-discipline helps ensure that the investigations will be of broad interest. Broad involvement also facilitates the dissemination of JWST expertise through a more extensive network, and promotes more equitable participation in JWST scientific discovery.

 The DD ERS program will be essential for informing the scientific and technical preparation of Cycle 2 General Observer (GO) proposals, submitted seven months after the end of commissioning.

Project Updates for the Community

A prime goal of the DD ERS program is informing the astronomical community of JWST's scientific capabilities . DD ERS teams will contribute to this goal by sharing progress on their projects, with special focus on lessons learned on JWST observation planning strategies, data processing, and science analysis. Webcasted briefings given by DD ERS teams, will be organized by STScI as part of JWST community workshops. Prospective DD ERS teams should account for the effort required to support such briefings in the workplan and budget outlined in the submitted proposal. DD ERS teams should plan to support two major briefings, 2-3 months after JWST launch, and ~1 month prior to the release of the Cycle 2 Call for Proposals. The exact schedule will be determined at a later date.

Status Reviews

To help ensure that the overall DD ERS program will achieve its stated goals, STScI will review the status of each project at key points. Where appropriate, review panels will include both STScI staff and external community members. The timing of the reviews will be such that materials prepared by the DD ERS teams for the reviews can used to inform the broader community in January and September 2019. The reviews will assess the progress of each team relative to schedule milestones and delivery of science-enabling products as described in their workplans, identifying challenges that arise, together with potential solutions. Continued funding will be contingent upon satisfactory progress at each stage.

The nature of each review is as follows:

  • Technical Review: Iterations between STScI staff and DD ERS teams to optimize programs will begin after the announcement of DD ERS review results in late October 2017.  Teams will provide basic documentation describing the rationale underlying their observing strategies. That documentation will be released to the community with the final APT files in December 2017. This will enable DD ERS programs to serve as templates for planning of Cycle 1 GO proposals.
  • Readiness review: Prior to the beginning of science observations, each team will report on their progress on preparatory activities and their readiness to process and analyze JWST data.  Preparatory activities might include analyses of simulated datasets to test post-pipeline data processing plans (if proposed), and customization and/or development of data analysis and/or software tools (if proposed). This review will occur 3-4 months prior to the beginning of science observations (2-3 months after launch).
  • Results review: Each team will report on the successes and challenges encountered based on the analysis of early data from their DD ERS project. The status of initial products that must be delivered by the release of the Cycle 2 GO Call for Proposals (7 months after the start of science observations or 13 months after launch) will be evaluated. This review will support a community briefing ~1 month prior to the release of the Cycle 2 Call.


Next: JWST DD ERS Proposal Policies

Related Links

JWST General Science Policies

JWST Director's Discretionary Early Release Science Call for Proposals

JWST Cycle 1 Proposal Opportunities

JWST Director's Discretionary Early Release Science Call for Proposals

JWST Opportunities and Policies