Attended: Bruce Balick, Chris Impey, Jay Frogel, George Miley (Chair), Felix Mirabel, Sergio Ortolani, Dave Sanders, Susan Terebey, Hal Weaver, Bruce Woodgate.

Unable to attend: Debra Elmegreen, Pat McCarthy

1. GENERAL

The ST Users Committee congratulates the Institute and NASA for the manner in which they have dealt with the need to operate the HST while simultaneously developing the NGST. It is apparent that satisfying the needs of HST users has been one of the most important drivers in the planning process that has taken place during the past year.

2. STATUS OF THE PROJECT

STUC recognizes the problems caused for the HST Project by the delay in scheduling the SM3A service mission and encourage all efforts to minimize delays in carrying out the subsequent SM3B and SM4 missions.

We compliment the HST Project for their decision to implement a near-IR capability on WFC3 without seriously impacting funding for the user science programs. The resultant enhancement of the wide-field imaging capability of HST should ensure that the HST continues to produce fundamental discoveries and continue to inspire the general public until the end of its life. The unique scientific opportunities afforded by such an infrared channel will benefit a large range of astronomical projects, including studies of the early Universe and the Origins Program.

3. REORGANIZATION OF THE INSTITUTE AND LONG-TERM COST REDUCTIONS

STScI is adapting from being an institute devoted to a single mission (HST) to one that can take simultaneous responsibility for several facilities (e.g. HST and NGST) in a period of constant funding. A necessary reorganization is underway to prepare for this changing role. STUC was impressed by the careful argumentation and wide consultation at all levels of the Institute that formed the basis for the reorganization plans.

The new obligations coupled with the budget cap has forced the STScI to embark on a cost-cutting exercise with respect to future HST operations ("Cheap-ops"), which will be finalized during the next several months. STUC is encouraged that the various options now being considered are sensitive to the needs of the HST user community and will preserve the excellent STScI support for observing programs that we have long enjoyed.

We encourage the pursuit of a planned pilot project that will outsource to the community a limited number of calibration tasks that have traditionally been the responsibility of the Institute. This is a reasonable way of (i) ensuring that certain little-used observing modes can continue to be offered (ii) harnessing technical expertise within the community in optimizing the scientific exploitation of the telescope and (iii) facilitating the development of possible new observing modes. We therefore consider it appropriate to devote a small part of GO funding in support of such activities. Particular candidates for outsourcing are (i) calibration activities for which major expertise already resides outside STScI, and (ii) rarely-used observing modes for which calibration can be more efficiently conducted by the allocation of additional orbits and funding to the GO program requesting such modes. In the latter case, the total cost in spacecraft time and resources should of course be made clear to the TAC before allocation.

It is desirable that proposals for outsourcing undergo some form of peer review, but this should be done in an efficient and inexpensive a manner as possible. We look forward to evaluating the success of the pilot project that the Institute has begun in Cycle 9. At this stage we do not envisage calibration outsourcing as comprising more than a very small part of the HST calibration activities. However, we recommend that the Institute consider the effectiveness of outsourcing the development of software to carry out data reduction tasks, for which appropriate expertise exists in the community.

Considerable technical expertise on the use of Hubble exists outside the United States and it is desirable that ways be found to ensure participation of non-US astronomers in such programs. In particular, we hope that the European Space Agency can provide a small amount of funding to permit a similar program to be funded in Europe, thereby involving European astronomers in efforts to enhance the performance of the HST.

The STUC was impressed with the care with which the STScI staff is streamlining the user support functions at the Institute. Plans to provide Contact Scientists only at request of a project PI, while augmenting resources of the Help Desk appear reasonable, but continued evaluation is needed to monitor possible effects of such measures on user support. The STUC looks forward to receiving feedback on the effectiveness of the new Contact Support procedures.

We understand the need to reduce the cost of user visits, by critically evaluating the need for such a visit and reducing the default period of full-time support by research assistants. However, when evaluating the need for such visits we urge the institute to take into account the (often intangible) role that such visits play in directly involving the community with the project and in particular in training young astronomers to be sophisticated users. In addition, the STUC encourages STScI to pay more attention to providing cookbooks, scripts and example files. Provision of such aids could improve the efficiency of data reduction and greatly reduce the time and effort spent by Institute support staff in training users to carry out basic reduction tasks.

An important part of any cost-cutting exercise is to evaluate total costs. We therefore support efforts by the institute to review all aspects of the step by step process by which science is produced and the importance of the various ingredients in determining the total cost of a project. We look forward to working with the Institute on a more detailed analysis of such matters in time for the next STUC meeting.

4. WFC3: SIMULTANEOUS IR/OPTICAL OBSERVATIONS

STUC received a request by the WFC3 Science Oversight Committee and the Project to evaluate the scientific importance of a proposed WFC3 option that would permit simultaneous observations with the optical and infrared channels of WFC3. After receiving written and oral presentations on the technical and scientific aspects, we considered this matter at length Implementation of a "simultaneous operations" option for WFC3, would add to the rapidity with which Hubble can gather data. However, we were presented with no compelling programs for which the ability to observe simultaneously in the optical and near-infrared would produce unique HST science, that could not be attained from the ground.

There is a "downside" to including the simultaneous observation option in WFC3, as it is presently conceived. Since the performance of the CCD detectors in the HST instruments is expected to decay over time, it is critical that the ability of the IR detectors in WFC3 to operate at as short a wavelength as possible should not be compromised. The dichroic optical element necessary for simultaneous operations would not allow the IR channel to operate below about 8500 Angstroms. The proposed option would therefore (i) reduce the redundancy in HST optical imaging capabilities and (ii) result in possibly reduced sensitivity in the wavelength region near 8000 Angstrom. We regard optimization of the efficiency of both presently planned channels and the preservation of redundancy to be more important than the ability to observe simultaneously in the infrared and optical.

The improvement in observing efficiency achieved by the simultaneous observing option would produce some enhancement in the scientific productivity of Hubble. However, in view of the above arguments and the tight budget constraints on WFC3 and the HST project as a whole, we cannot recommend implementation of the simultaneous operations option as presently envisaged.

5. SOFTWARE TOOLS

5.1 STSDAS. We are extremely enthusiastic about the innovative work of the STSDAS group in developing the use of Python as a command language interface to IRAF. As well as providing a modern platform for developing astronomical image processing software, this project holds out the promise for significantly improving users' ability to reduce and analyze data. The new (backwards-compatible) IRAF platform could be an important element of the "Cheap-ops" mode of operation at STScI. In view of its promise for reducing the time and effort needed to create application software, it could improve the productivity of STScI's software programmers considerably and greatly expand the pool of potential contributors to HST's data analysis tools. We also note the tremendous potential that this new STScI project might have for future missions and general astronomical data analysis. We are impressed by the relatively small effort that has so far been required to reach the present stage of the project. However, as the project progresses, it is important to have clearly defined milestones for the software developers and careful reviews by Institute staff and outside users who will be making use of Python. Several STUC members have volunteered to participate in this process.

5.2 SEA/APT. During the last meeting STUC was introduced to a prototype of the Science Expert Assistant (SEA), a program that is being developed mainly as a replacement for RPS2. It was clear that the enhanced scheduling capabilities of SEA with respect to RPS2 could effect qualitatively the scientific use of HST. A sub-group of STUC (Impey, Sanders and Woodgate) was set up to conduct a more detailed evaluation the SEA. At the present meeting we considered the present status of the project, which has since been renamed the "Astronomer Proposal Tools" (APT).

The visual windows-style interface, coupled with easy access to both NED and the digital sky survey are important and useful aspects of APT. In particular, the Visual Target Tuner (VTT) will allow proposers to optimize their observations and should facilitate significant gains in serendipitous and parallel science. While APT promises to be an important aid to astronomers in developing their proposals, the tools are not yet ready for general release.

One major concern is the slowness of the package, even when running on a Sun Sparc 10 workstation with 128 MB of memory. APT needs to operate efficiently on computer platforms typically used by the average university astronomer. There are still a substantial number of bugs and limitations in the pre-release version - no possibilities for local printing or import of text or RPS2 files, context-sensitive help and zoom functions that would not reactivate and details of the visual interface that are not intuitive. The RPS2 process is still time-consuming and cumbersome: APT should offer simpler (default) paths to optimizing observing strategy. In addition, it would be useful to have a high-level "brainstorming" tool to allow potential proposers to test the feasibility of projects, without having a detailed knowledge of HST instrumentation.

STUC endorses the continued development of APT. If possible, the VTT should be made available as a prototype tool for Cycle 9 Phase II planning. Hopefully, a general release of APT that incorporates an exposure time calculator can be ready in time for Cycle 10. We look forward to continued involvement in setting priorities for APT development. STUC recommends that the APT effort should be re-evaluated when feedback is available from a larger set of users and in particular in the light of the experience of Cycle 9. Finally, we encourage the STScI to continue to improve the last stage of the Phase II process, in which various activities are laid down within each orbit, so that users do not waste time and effort trying to optimize their observing programs.

6. OTHER MATTERS.

At the end of the present Millennium Pat McCarthy, Susan Terebey and Bruce Woodgate will rotate off STUC. The Director of STScI and the Chairman of STUC thanked them for their contributions. The dates of the next STUC meeting will be 6^th and 7^th April 2000.