All proposals will be reviewed together in the same peer review, and it is expected that a mix of large, medium, and small programs will be selected. It is anticipated that about 50 investigations containing approximately 80 new observations will be selected from proposals received in response to this Announcement. Too many such time-critical observations would compromise the ability of the mission planning and operations team to effectively schedule the full set of requested observations. Because all time-critical observations drive the scheduling process and, therefore, must receive highest scheduling and scientific priority, their total share must be kept relatively small. Observations in this category are those with high scientific importance of rapidly evolving phenomena whose occurrence is not predictable.
Prominent examples are supernovae or x-ray transient outbursts.
Data from preapproved TOO's will be proprietary to the PI for one year. Note that a proposal cannot include both TOO's and regular observations, even of the same object. Proposers should check whether their targets of interest are to be observed. If this is the case, the need for additional observations of those sources must be justified.