Director's Discretionary (DD) Time Proposals

Directors' Discretionary Time proposals are discussed in this article, including the circumstances under which they are used and how to submit them.

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Time-critical DDT proposals

Time-critical Director's Discretionary Time proposals might be appropriate for:

  1. follow-up of newly-discovered unexpected transient phenomena, or when developments since the last proposal cycle make a time-critical observation necessary;
  2. the timely follow-up of new discoveries that will provide a critical link in the understanding of the phenomena. 

Requests to reserve target of opportunity targets that have not yet been discovered are not appropriate for Director's Discretionary Proposals.

Please note: All scheduling requirements must be specified, including timing requirements that would require disruptive (< 14 days) or ultra-disruptive (< 48 hours) turnaround times for activation. The limitations on each of these are described in JWST Target of Opportunity Observations. Proposals that imply a time requirement, e.g., "as soon as possible," but do not specify a disruptive or ultra-disruptive activation time, will be returned. There are a limited number of ultra-disruptive activations available in Cycle 1, so please justify accordingly.

Once a proposal is approved, any subsequent requests for changes may jeopardize the execution of the program and will be accepted only under highly exceptional circumstances.

Time-critical DD observations should not generally be requested if any of the following is true:

  • The observations could plausibly have been proposed in the most recent regular proposal cycle, possibly as a target of opportunity proposal;
  • The observations were proposed in a recent regular proposal cycle, and were rejected;
  • The proposed observations could wait until the next proposal cycle with no significant reduction in the expected scientific return.

Subject to availability of funds from NASA, STScI will provide financial support for U.S. PIs and Co-Is of approved DD programs.

Time-critical DDT proposals will be available to the community on July 12, 2022.
More information about past and present opportunities is available at JWST Director's Discretionary Time



DDT proposal preparation

DD proposals must now be submitted and will be reviewed in an anonymous format. The review process is similar to that used in the JWST Cycle 1 anonymous review, except the review of the team expertise will be done internally by the Science Policies Group. There is no need to submit a separate "Team Expertise and Background" document.

Proposers should use the Astronomer's Proposal Tool (APT) to submit their DD programs. To download and install APT, go to the APT webpage. For help on using APT to prepare and submit a JWST program, please refer to the Getting Started with JWST Proposing article. You will be providing all necessary information (including all necessary observing parameters) via the APT tool and you will attach your scientific justification and observation description as a PDF attachment to your submission, as is typical for JWST GO proposals. More detailed information is included below.

Templates for the PDF attachment of the "Scientific Justification" can be found on the current cycle's proposal preparation article. Page limitations should follow the Page Limits for the PDF Attachment for proposals of the same-sized proposal category, as shown on the JWST Cycle 1 Proposal Preparation page.

Upon completion of your DD submission, your program will be transferred to the STScI for processing by our DD team. If you run into problems submitting a DD request, send contact the JWST Helpdesk for investigation and resolution.

Please refer to the section on Director's Discretionary Time proposals in JWST Proposal Categories for policies regarding DDT proposals.

Proposals for DD time must be sufficiently detailed for adequate evaluation. The required level of detail is the same as that required for proposals submitted for the regular observing cycles, as described in the current James Webb Space Telescope Call for Proposals for Cycle 1. 

Among other things:

  • both the proposed observations and the use of DD time must be explicitly justified;
  • there must be an adequate description of how the proposed observations relate to the current state of knowledge;
  • the proposed observations must be described in sufficient detail to allow technical evaluation;
  • the APT file must be telescope-ready.




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