Observing Rules: 4. Modification of AORs

4. Modification of AORs

• All programs executed by the Spitzer Space Telescope are properly reviewed and approved. The approval process described below is intended to ensure that the modified program, as executed, is approved and avoids duplicate observations.

• All modifications shall be such that the program stays within its originally allocated observing time.

The procedures described here exclude the procedures that will be followed in the catastrophic loss of a major instrumental or telescope function.

Checklist for Requesting Modification of AORs

4.1 Types of Modifications

All requests for modification of approved AORs must be approved by the SSC Science User Support Team, which will characterize the request as one of two types. Minor modifications consist of small changes of target parameters, typically a few arcseconds in celestial coordinates, or small changes in AOR execution time (< 20%), subject to the total observing time in an investigation remaining constant. Minor modifications could also include small changes of other parameters in the AOR (e.g., change to high-dynamic mode in the IRAC AOR), as long as the changes do not alter the scientific content or intent of the original AOR.

Major modifications to an individual AOR consist of those changes that would substantially alter the scientific content or intent of the AOR. Examples of major modifications include:

• Changing the observing mode for an observation (e.g., from MIPS scan map to IRAC imaging).
• Changing the execution time of an AOR by 20% or more, thereby increasing the probability that duplicate observations might arise.
• Changing the sensitivity by a factor of 1.5 or more.
• Changing the target coordinates, or boundary area, by an astronomically significant amount.
• Changing the target to a different target judged by the investigator to be scientifically equivalent to the original target.

The execution of an approved observation may become infeasible (Section 12) or prove to be scientifically useless because of unanticipated circumstances. If these events occur, and if a General Observer can a priori demonstrate that the approved AOR will yield useless data, the Principal Investigator can submit a request to make major modifications to the AOR. The proposed modifications must be consistent with the original scientific intent of the approved observation and the observing time granted. In addition, it cannot duplicate any other approved observation, and must be approved by the SSC Director.

Requests for major modifications to any approved observing program or AOR must be made to the SSC Science User Support Team through the Helpdesk (help@spitzer.caltech.edu), and must be accompanied by adequate justification. Modifications are contingent upon approval by the SSC Director, or designee. Once the request for a modification is approved, the requestor may modify the AOR/program, with assistance provided by SSC Science User Support Team. The latter is responsible for insuring that the modifications are implemented as approved.

4.2 Blackout Periods

An exception to the ROC freeze during active CPs will be granted to successful Spitzer Fellow applicants that are awarded observing time as part of their fellowship. These observations will take precedence over duplicate observations proposed for the next Cycle. A maximum of fifty hours of observing time can be awarded annually with the Spitzer Space Telescope Fellowships.

Checklist for Requesting Modification of AORs

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