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Proposal Kit

Director's Discretionary Time (DDT)

Spitzer is accepting DDT proposals: Read Me First!


We strongly encourage observers who are considering submitting a DDT proposal to do so as soon as possible. The later your DDT proposal is received, the stronger the science case will need to be in order to be accepted.
Please check the visibility windows of all targets before writing your DDT proposal. Many parts of the sky have no visibility windows left. You can find directions on how to do this in the Observation Planning Cookbook section 2.4.2
Please email us at if you want to check on the feasibility of scheduling your observations before you write your proposal.
Any DDT proposal submitted after May 3, 2019 must include a brief description of why it was not possible to submit the proposal by the deadline. This text should be included in the "Other Comments" box on the proposal submission webform. The review of time-critical proposals will be done as rapidly as resources allow.

Please note that the final date for executing Spitzer observations will be January 29, 2020.


    To submit a Spitzer DDT proposal fill out this online submission form, which includes:

    • Standard coversheet information (PI and Co-I contact information, proposal title, etc, as for a regular General Observer submission).
    • Complete Astronomical Observation Requests (AORs).
    • A strong scientific justification (must be in PDF format), specifying why the request was not submitted during the normal Call for Proposals and the long-term legacy value of the observation. Please use the templates:

    Please upload both the science justification and the AORs via the online form.

    Note that requests for DDT cannot be used to resubmit all or part of a proposal that was rejected by the normal peer review process.

    Guidelines for Submission of Director's Discretionary Time Proposals

The Cycle 14 Call for Proposals is now closed. Proposals were due Friday, 23 March 2018, 2 PM PDT

Cycle 14 proposal templates
AOR file parser - perl script for preparing observation summary table from your AORs.
Older Calls for Proposals
Proposal and Program Statistics
Note for Solar System Observers

A longer cookbook-style document on how to go from an idea to a set of fully-functional Astronomical Observation Requests (AORs) for your Spitzer proposal.
Spot is a software package used by Spitzer observers to plan observations, and Leopard is a software package used to query the archive. Together, this group of cats is referred to as the "Spitzer Pride."