How to apply for ToOs
Requests for observations of these objects should be submitted through the normal General Observer proposal process in response to a Call for Proposals. Observations of completely unanticipated phenomena can be requested through DDT procedures.

Medium- and high-impact ToOs can only be applied for as Director's Discretionary Time in Cycle-6 and up.

How to activate a ToO
For approved programs with low-impact ToOs, the Principal Investigator (PI) or Technical Contact (TC) for the program should email the Spitzer Helpdesk to request activation. The email should contain detailed information about the ToO target and how it satisfies criteria for activation outlined in the approved proposal. Remember that low-impact, being defined as more than 5 weeks out, does not mean 4 weeks plus one day...

A General Observer proposal must include a valid Astronomical Observation Request (AOR) for each predictable ToO observation. The AOR must be completed in as much detail as possible, lacking perhaps the precise target position (i.e., a null target) and refined integration times. The proposal must present a detailed plan of observations that will be implemented if the specific event occurs. Moreover, it must also provide an estimate of the probability of occurrence of the specified event during the relevant Spitzer observing cycle(s).

After a ToO proposal is approved, a request for AOR activation must be electronically submitted to the SSC Director by the Principal Investigator (PI) via the Spitzer Helpdesk. Following the request for activation, the SSC will ascertain the feasibility of conducting the ToO observations, taking into account sky visibility and the schedule of Spitzer instrument campaigns. The observer will also submit a revised AOR, with precise coordinates and integration time. If the observations cannot be conducted on a schedule requested by the investigator, the SSC Director will consult with the PI on the scientific utility of later observations. The SSC Director must issue final approval for any high-impact ToO observations requiring an interruption of the onboard observing schedule.

An approved ToO observation will be executed only in the event that the specified phenomenon actually occurs within the relevant observing cycle. If the triggering event for an approved ToO observation does not occur during the observing cycle, the AOR will be deactivated at the end of the cycle. In the event that a ToO observation expires without execution, the allotted observing time will be returned to the General Observer pool.