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UCO home > Observing > Keck Observing > ToO Observations at Keck

UC Keck Telescope Time for ToOs

Target of Opportunity (ToO) proposals should be directed at objects of unpredictable appearance dates for which a short, timely observation (up to one hour) may be of great value. The TAC will evaluate ToO proposals. Those that receive approval will be sent by the Director to all relevant potential observers for their advance study. Should a ToO event occur, it is the responsibility of the ToO proposer to arrange with the scheduled observer for the observations to be made. It is not mandatory that the observer carry out observations of the ToO event, but a well-written, persuasive proposal should increase the likelihood of this. ToO proposals are due the same date as others and should be clearly indicated as such.

Download pdf of currently approved UC ToO Projects

Policy Update

June 23, 2011

Dear colleagues,

At the last UCO Advisory Committee meeting there was an extensive discussion of the UC Target of Opportunity (ToO) rules for Keck Observatory-based observations. At the end of the discussion, the committee voted in favor of making the new policy as follows (from the notes of the meeting):

"The UCOAC voted on and approved a proposal that all UC programs allocated at least one night of observing time will be subject to donating up to one hour of each night to approved ToO programs. The observers will be able to briefly negotiate when to take the observations (e.g., to delay until completion of a current exposure, if necessary), but they are discouraged from questioning the scientific merits of these TAC-approved programs. The one hour per night is actual clock time from the termination of the observer's own program and includes the overhead for the observer to configure the instrument for the ToO observation and to reconfigure the instrument to resume the normal program. Coauthorship on a resulting paper will be offered to the observer. This policy will start in Semester 2011A. The TAC will recommend a specific number of maximum hours for approved ToO programs and the actual interrupts will be tracked each semester."

The UC Keck Time Allocation Committee will be made aware of this change for their consideration of ToO program requests.

Upon activation of a ToO program, an email should be sent to Robin Horn ( listing (1) the PI interrupted (2) the instrument used, and (3) the total time allocated to the ToO project.

Regards, Mike

Director, University of California Observatories
University of California, Santa Cruz