Report of the
Space Telescope Users Committee
May 1998
The Space Telescope
Users Committee (STUC) met in open session on 18-19
May 1998, in the Board Room of the Space Telescope Science Institute.
Committee members in attendence were: B. Balick, J. Bally,
J. Clarke, L. Kay, P. McCarthy, F. Mirabel, R. Schulte-Ladbeck,
S. Terebey, R. Thompson,
F. Walter (Chair), H. Weaver, and B. Woodgate.
Absent were R. Fosbury, J. Frogel, and S. Ortolani.
Minutes of the meeting are reported elsewhere.
Readers should note that this report is based on information presented to
the STUC in May 1998, and may be superceded by
later developments. Readers are urged to refer to the
STScI web pages
for up-to-date information.
Executive Summary
The tenor of this meeting was generally positive. HST continues to operate
well. NICMOS is performing as advertized.
The NICMOS Cooling System is looking more practical.
Plans for SM3 are advancing towards a May 2000 mission.
The projected funding for the HST project looks good through 2010,
to the extent that any budgetary projections can be believed.
NASA and the STSCI are beginning to plan how to operate HST
at low cost after 2003. And a new director has been appointed to lead STScI
into its second decade.
The personnel at NASA Headquarters who manage space science programs
were delighted that Congress recently listed "science" as NASA's
top priority, and this new emphasis creates optimism for the future
of space science endeavors at NASA, although the imminent departure of
Wes Huntress, who has beeen an effective advocate for science at NASA,
does create some uncertainty.
However,
the committee had a number of concerns about the adverse impacts
caused by the apparent inadequate staffing of STScI on the capabilities of
the HST. The committee expressed concerns about perceived imbalances
on various review panels and committees. And the performance and calibration
status of the
ACS continues to be a concern.
The Second Decade Study
It is clear that NASA is serious about
continuing to operate HST through 2010, and the STUC enthusiastically supports
this. NASA has convened the Second Decade Study to recommend how to best
utilize the HST in an era of reduced support, and in concert
with a new array of supporting technologies, including AXAF, XMM, SIRTF, SOFIA,
NGST, GEMINI, and the VLT. Although purview of the Second Decade
Committee is somewhat
limited because the final instrument complement is set, it has the
charge and responsibility to develop observing strategies for HST to
maximize its scientific potential in the context of changing programmatic needs.
The STUC is concerned that the Second Decade Committee
is inappropriately constituted to meet this challenge.
The STUC feels that a committee which lacks sufficient breadth
to appeal
to the full astronomical community will not gain the respect of the full
community, and that its recommendations may not be taken seriously. HST will
need broad support from the community to continue to operate during this
second decade.
The STUC has delivered a brief report to the Second
Decade Study Committee. We are heartened that the committee membership
has been augmented in reponse to some of our concerns.
STScI Manpower
A number of instrument capabilities, particularly on STIS, are not yet
implemented. This is directly attributable to manpower limitations. We
encourage a review of the distribution of reponsibilities, in the expectation
that this could lead to an enhancement of the resources available for
instrument, observer, and operations support.
Proposal Evaluation
The information content returned to the proposers from the Cycle 7 archival
research proposal
reviewers was far superior to the checklist used during the Cycle 7 delta CP.
Reviewers thought that the checklist was a good tool for internal use, but
the proposers felt that it failed to convey any sense of the rationale
for the decisions. We encourage STScI to retain written reviews for
Cycle 8.
We urge the STScI to instruct the reviewers to
put themselves in the place of the proposers, and to
write a review sufficiently detailed that proposers will understand why their
proposals were so evaluated.
The STUC noted some apparent problems with the Cycle 7 delta-CP and
archival research reviews. In the Cycle 7 delta-CP review, proposals
targeting star formation and circumstellar disks were spread over two panels,
neither of which appeared
to have much expertise in this area. Consequently, a surprisingly small
number of orbits was allocated for star formation studies,
despite the excellence of NICMOS for tackling problems in these areas.
Similarly, a lack of panelists with expertise in spectroscopy of cool star
chromospheres and coronae may have contributed to the lack of successful
proposals in this area in the Cycle 7 AR CP.
The greater number of panels (and panelists) in the Cycle 7 review led to
a fair treatment of these and other scientific areas. We are cognizant
of the difficulties involved in assembling review panels, and we understand the
difficulty of providing experts in all possible fields for the
smaller supplemental reviews, but we urge the STScI to make a strong effort to
ensure fairness and balance in the review process.
Archive Users Survey
The STUC generally concurs with the conclusions and recommendations of the
1998 Archive Users Survey. The STUC is enthusiastic about the plans to implement
the On-The-Fly-Calibration system. We agree that paper products are important,
but that the number of pages produced could be reduced, especially in cases
(like NICMOS) where the typical observation has hundreds of observations.
HST Scheduling
The experience of Cycle 7, with the unforeseen difficulties with NICMOS
mandating the delta-CP, is one we would all like to put behind us. For GOs
and the STIS GTO team, the deferral of STIS and WFPC2
observations into 1999 has, in many cases, caused both scientific and
financial hardship.
At the
urging of this committee, the archival Call for Proposals (CP)
was issued to provide users
of the archive an interim opportunity independent of the
drawn-out observing cycle. The STUC thanks the STScI and the HST project for
their responsiveness. The STUC realizes that
these unplanned CPs involved much effort, and applauds all involved
in successfully implementing these extraordinary calls for proposals.
The STUC welcomes the return to 1 year durations for Cycles 8 and 9. We
look forward to predictability in the dates of future cycles,
and strongly support the objective, being pursued by the STScI, of creating
a stable Long Range Plan.
Planetary Working Group
The new capabilies for planetary and moving target observations
(discussed in the minutes)
continue to be important for the production
of high quality science from HST. The STUC encourages STScI
to continue the development of these capabilities.
In particular, we believe
that the routine distribution of finding charts to observers
will be valuable in heading off pointing problems, which have
plagued observations in the past, before they occur, thereby
also improving observing efficiency.
There is a specific problem with some observations using track 51 tracking.
Often, in a sequence of exposures using different
filters, apertures, etc., the absolute
pointing within the field of view is crucial for the comparison
of the exposures. However,
the present software creates a new alignment with a new
pointing, differing typically by 1-2 arc sec in some random
direction, whenever any of a series of parameters is changed
in the phase 2 proposal, including the aperture, target name,
etc. In the case of STIS, several different filters have
unique aperture names defined for them. It is not
possible in the phase 2 proposal to obtain co-aligned images,
for example, with the UV-MAMA clear and with any filter, since
each of these exposures is required to be performed with a
different aperture name. We request that the STScI look
into this matter, modify the ground software to enable co-aligned
observations under track 51, and report back to this committee.
The Proliferation of Committees
There are many committees and ISRs advising STScI and the
HST project these days. These committees are often called into existence
to examine a single narrow aspect of the HST operations.
The STUC, as the standing committee representing the interests of the users
of the HST, is concerned that these committees and ISRs may not understand
the history and context of the actions, and its impact upon the HST users.
We request that the STUC be informed of the creation of such committees and
ISRs, and that the STUC be represented on these committees, either through
explicit membership or in an ex-officio manner.
Advanced Camera for Surveys
The STUC remains concerned about the status of the ACS. It is clear that
fiscal issues are compromising the ACS ground testing and calibration
programs, particularly in regards to the solar blind camera (SBC).
We strongly advise the project
to aggressively seek ways to provide the appropriate resources for this very
important effort. The HST project should not jeopardize the long-term
scientific potential of the ACS due to a short-term financial problem.
The STUC was told that the typical GO data set from an ACS observation would
total nearly 9 Gb, and would require a high-end workstation to process and
analyze. We trust that this need will be taken into account when grants for
projects involving ACS data are awarded.
The NICMOS Cooling System
It is clear to the committee that NASA is pursuing a cautious approach to the
NICMOS Cooling System (NCS; formerly the cryocooler). If
the NCS can extend the useful scientific life
of the NICMOS, with no adverse impacts upon the safety or operational
capabilities of the HST, this committee endorses the concept.
WFC3
The STUC endorses NASA's plan to replace the aging WFPC2 with a
new and more capable camera, presently known as WFC3. The straightforward
design approach helps to insure the presence of an important research tool
of low cost and high value intended primarily (but not exclusively) for
galactic studies that can complement the Advanced Camera. The WFC3 will be
an exciting instrument for the second decade of HST operation, especially
for narrow-band imaging of emission-line regions, including H-H objects,
all sorts of ionized stellar outflows (e.g. LBVs, supernovae, post-AGB
stars), and the ejecta from relatively-low-redshift AGNs. In tandem with
STIS, WFC3 will be the premier tool for studying gas morphologies and
kinematics in many types of objects.
The WFC3 will be a popular user
instrument, but its realized scientific utility will be
very sensitive to the selection of its filters. STUC applauds the plans
for community wide-study of the filters (to be conducted by the WFC3
Scientific Oversight Committee now being organized).
The STUC urges that the HST project see to it that the scientific
oversight committee is balanced between galactic and extragalactic interests.
The STUC wishes to be appraised of the selection of filters prior to the
selection being finalized. We suggest that a member of the STUC be appointed
to the SOC in either an active or ex-officio capacity.
Given that the current design of the WFC3 draws more on the heritage of
the ACS than it does on the WFPC, we concur with the suggestion that NASA
seek another name for this instrument.
GATOR
The STUC applauds the proposed acceleration of the funding of HST grants,
which is
one goal of the Grants Administration Team for Organizational Reengineering
(GATOR) project. However, we are concerned that the funding algorithm
will be too general to adequately account for the disparity of budgetary
needs. Judgment of the complexity of the data reduction and analysis, and
of the funding needed, should ultimately remain in the purview of the PI.
Observers must not be penalized for working at high-overhead
institutions, nor for living in regions with high costs of living and salaries.
The STScI must realize that graduate students can rarely be
employed for periods shorter than a semester or a summer, and that PI summer
salaries should be allotted in units of man-months.
The STUC also feels that the Grant's Office's projection that only 10% of the
PIs will appeal is on the low side.
The STUC looks forward to the report, in a year's time, detailing
how accurately the funding algorithm predicts the
requested budgets during Cycle 8.
The Director
With deep admiration and gratitude the STUC
recognizes the many scientific and administrative achievements made by the
outgoing Director of the STScI, Dr. Robert E. Williams. Bob kept a steady
hand on a large, successful, and high-momentum organization during times of
financial havoc and staff reductions early in his tenure. The Institute
emerged leaner and meaner, and it has maintained a record
to be admired by the entire astronomical community.
HST users have benefitted from Bob's commitment to a
simplified proposal process, his strenghtening of staff orientation to user
requests, and his continuous enthusiasm for new HST instruments and
initiatives. All during this time Bob maintained an active research
program, most notably contributing in many important ways to one of the
premier astronomical experiments of the 20th century: the Hubble Deep
Field. The STUC has always found Bob to be an engaged listener, a forthright,
dependable, and enthusiastic partner, and an always-cheerful sport in the
parrying that characterizes STUC meetings.
We wish Bob Williams an active,
productive, successful, and satisfying return to a life outside the
Director's Office, and we look forward to equally good relations with the
new director.
This report submitted by
Frederick M. Walter
on behalf of the Space Telescope Users Committee
July 1998
fwalter@astro.sunysb.edu
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