Partnership Target of Opportunity (ToO) observations on Keck
July 1, 2016: approved by SSC
Target of Opportunity (ToO) proposals are directed at objects with unpredictable appearance dates for which a short, timely observation (up to one hour) may be of great value. This Partnership ToO
program is not intended for observations that can be anticipated in advance (e.g. Cadence observations).
We anticipate a 2 year trial period for this Partnership ToO policy, with a review after the first year. Updates may be needed when the Keck I deployable tertiary becomes available.
1. Caltech, NASA, UC or UH researchers can propose to their respective TACs for crossinstitutional
ToO (“Partnership ToO”) observations on Keck I and/or Keck II. TACs should award Partnership ToOs
only for highly ranked programs.
2. Each TAC will judge their respective community’s proposals. Each TAC can allocate up to a
combined total of six Partnership ToO + Partnership Snapshot observations per semester. Each TAC
will submit a list of approved Partnership ToOs to WMKO as part of the routine reporting of successful
3. WMKO will develop a web interface for managing ToO implementation, including listing approved
programs, accounting for time used and remaining, reporting ToOexempted nights, etc. This will be
the primary conduit for ToO PIs to initiate Partnership ToOs.
4. The ToO PI is responsible for contacting the classically scheduled PI (“Observing PI”) as soon as
possible. For a given night's observing, the first ToO PI to trigger an interrupt is the one that gets to
observe (a.k.a. first come, first served). The WMKO web interface will be the sole source for managing
5. Any ToO program that requires LGSAO must be invoked and the target coordinates submitted prior
to 3:00 pm HST on the day of the observing run.
6. For each ToO interrupt, the maximum duration is 1 hour of elapsed time (i.e. wall clock). No
instrument changes. This includes calibration and restoring the instrument mode to its state prior to the
ToO interrupt or to another state as mutually agreed with the Observing PI.
7. The Observing PI will make best efforts to promptly turn over the telescope to the ToO PI. The
observer may briefly delay handover of the telescope in order to complete their current exposure or
essential observing sequence (e.g. one AB nod pair). After that, it is expected the Observing PI will
yield the telescope to the ToO PI, unless the latter agrees to wait longer. The PIs should inform the
WMKO Observing Assistant when a Partnership ToO is invoked.
8. It is the responsibility of the ToO team to carry out the observations. The ToO team may carry out the
observations themselves. If remote observing, the team is responsible for making appropriate
arrangements with the Remote Observing Room, including reservations and testing in advance.
Alternatively, the ToO team may ask the Observing PI to carry out the observations, which will include
an offer of coauthorship; the Observing PI is not obligated to do the observing.
9. Upon completion of the ToO, the ToO PI is encouraged to use the Keck web system to submit a brief
summary of the execution of the ToO.
10. No more than one ToO interrupt per night per telescope. Also, the following are exempt from ToO
interrupts: (1) observing programs with allocations that are a halfnight or smaller, (2) nights that already
have 3 programs scheduled, and (3) nights with a Snapshot already scheduled (see accompanying
11. Individual TACs may designate a few nights (partial or whole) as exempt from ToO interrupts. This
designation must be scientifically motivated, namely that such interruptions would seriously
compromise the scientific return of the entire observing time. Proposers should make any such
requests to their individual TACs as part of their observing proposal. Use of these exemptions is
expected to be rare occurrences. Nights designated as “uninterruptible” should be clearly identified as
such, e.g., via the aforementioned web interface.
12. At the conclusion of each semester, WMKO will report to each partner the time used, the associated
ToO programs, and the interrupted Observing PIs.
13. Time imbalances between partners arising from Partnership ToOs will be corrected through each
partner’s semesterly time allocations and/or WMKO’s giveback science time. Since ToOs are only
executed in suitably good weather, their time usage will be charged at a rate of 2x larger than normal
observing time. (Any compensation to individual PIs interrupted by ToOs will be left to the discretion of
the individual institutions.)
Updated August 11, 2016 by UCO Director Claire Max.
Policy for UC Keck Time for Cadence Observing:
UC, NASA, IfA, and possibly Caltech have discussed plans to attempt a partnership “cadence” program for 2016B. The goal is to be able to schedule brief (e.g. one hour or less) observing sessions at times that are known far in advance, and to be able to interleave these into the regular observing schedule without the types of scheduling stress that have prevailed in the past. Details of how this will take place have not yet been fully worked out.
For UC proposals in Semester 2016B: If you believe your proposal fits into the "Cadence Observing" category please explain your needs in some detail in your proposal. Scheduling half-nights is considerably more straightforward than scheduling one-hour or quarter-night observing sessions. So if you have meaningful science that can supplement your brief cadence observing during the same half-night, please indicate this as an alternative to cadence scheduling, in case the latter cannot be arranged soon enough for Semester 2016B.
Updated February 21, 2016 by UCO Director Claire Max.
Policy for UC Keck Time for Targets of Opportunity
Currently Approved UC ToO Projects at Keck, updated July 15, 2015.
||HIRESr Keck I
||NIRC2-LGS Keck II
||NIRC2-NGS Keck II