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STScI Newsletter
2023 / Volume 40 / Issue 02

About this Article

Beth Biller, with Laura Watkins (lwatkins[at]

The Hubble Space Telescope Users Committee (STUC) is a group of 12 scientists that meets twice yearly with the members of the Hubble Team from the Space Telescope Science Institute (STScI) and NASA. The purpose of the STUC is to represent the views and interests of the Hubble Users community. Therefore, you are encouraged to contact the STUC with any issues you may have relating to Hubble policies, proposing and utilization. We are here for you.

Hubble peeks into nearby star-forming region NGC 1333
This Hubble photo is of the nearby star-forming region NGC 1333. Located in the Perseus molecular cloud, this nebula is approximately 960 light-years away. The image was released in April of this year in honor of Hubble’s 33rd launch anniversary. Credits: Science by NASA, ESA, STScI and Image Processing by Varun Bajaj (STScI), Joseph DePasquale (STScI), Jennifer Mack (STScI)

The STUC met in person on May 8 and 9, 2023 and welcomed three new members: Ata Sarajedini, Harry Teplitz, and Matthew Hayes. Perusing the presentations to the STUC and reading the STUC report itself for each meeting is an excellent way to get an inside view of what is going on with HST and at STScI! Here are some of the highlights from the presentations to the STUC this time around:

  1. Neill Reid gave the STUC an update on the ongoing search for the next STScI director. A diverse selection committee with a wide range of expertise and backgrounds has been assembled. A good number of applications were received and the committee is currently reviewing the applicant pool and identifying a long-list for video interviews. 
  2. Previous STScI directors have convened Working Groups to consider large-scale initiatives. In the preceding iterations of this process, the recommendations of the Hubble Deep Field Working Group led to the Frontier Fields program, the recommendations of the Fundamental Physics with Hubble Working Group led to the Fundamental Physics Initiative, and the recommendations of the UV Star Formation Working Group led to the Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) Director's Discretionary (DD) program. Interim director Nancy Levenson has constituted two new Working Groups to consider: 1) strategies and priorities for exoplanet observations with HST and JWST and 2) strategies and priorities for long-term monitoring programs with HST and JWST. These working groups are charged with identifying potential large-scale programs that could be undertaken with Director’s Discretionary Time in JWST Cycles 2 and 3. 
  3. Neill Reid also presented plans for a new set of Multi-Cycle Treasury Proposals (MCTPs). The first set of MCTPs ran in HST Cycles 17-19. The new set to be solicited will run from HST Cycles 32 to 34.
  4. Hubble celebrated its 33rd anniversary on April 24th and is still producing world-leading science!  Tom Brown gave us an update on the current status of Hubble and its instruments. Overall, all instruments are working nominally and there is large-scale planning in place to ensure the Institute staff are not overstretched in their responsibilities in the current era of simultaneous Hubble and JWST operations. Tom also told us about the new “Flexible Thursday” Target of Opportunity (ToO) mode, which will be offered for the first time in Cycle 31. The STUC looks forward to hearing more about the full implementation of this mode and its use by the community.
  5. Jennifer Wiseman and Jim Jeletic presented an update on the Goddard HST Project. Jennifer showcased some of the HST images and data that have been highlighted in the press including the Hubble anniversary image, isolated white dwarf mass measurements, and a runaway black hole or edge-on galaxy. Jim presented information on the Hubble budget assigned by NASA HQ which has been flat for over a decade at $98.3M. Jim and Jennifer made it clear that the flat budget extending from FY26 to FY29 would mean that they would no longer be able to support the program as it currently is - i.e. if there is no relief to offset inflation, the Grants budget will see a 40% reduction in funding as operations costs cannot be further reduced. The STUC supports and implores NASA HQ to match the Hubble budget to inflationary rate and that full support is required to continue successful use of the mission. 
  6. Claus Leitherer reported on the Mid-Cycle reviews for Cycle 30 as well as the Hubble Cycle 31 TAC process. After the May Cycle 31 deadline, from Cycle 32 onwards, Hubble deadlines will now return to the usual March / April deadline. The STUC notes that discussion of success / failure rates by proposer gender hinges on the concept of “estimated gender” based on name / details on websites, as it is not legal to mandatorily collect such details from proposers. The STUC is now familiar with this concept via presentations on HST Cycle statistics, but recognizes that community members may not be.
  7. Julia Roman-Duval, Jo Taylor, and Will Fischer provided an update on the ULLYSES project, which is set to conclude this year. ULLYSES leverages archival UV data from multiple sources (including HST and recalibrated FUSE) with new HST COS/STIS observations, with about 500 orbits devoted to spectra of high-mass low metallicity stars, and about 500 orbits devoted to spectra and time series of young T-Tauri stars. The T-Tauri spectra are supplemented by about 11,000 photometric measurements from the Las Cumbres Observatory Global Telescope Network (LCOGT) to provide temporal context. The new HST data include other star-forming regions to supplement Taurus, which dominated the archival component. Twelve early papers have been published, the main survey paper is in preparation, and presentations have been made at conferences and other venues. A ULLYSES workshop will be held at STScI in early 2024. The ULLYSES team developed a custom search form following the MAST framework, and data can also be accessed through MAST portal links. The team produced software tools to splice and coadd spectra, including spectra from different instruments, and these tools are being generalized and provided to the community.
  8. John Mackenty presented STScI’s plan for the Gap Filler programs. These programs provide a pool of targets for short observations that can be added to the schedule late in the process in order to improve observing efficiency and add value to the Hubble archive. John reviewed the history of the program, described the process for recommending new programs, and then the STUC held a discussion for making the recommendation. STScI reviewed 39 submitted proposals, of which 33 were compliant with the Call for Proposals. This initial review was conducted by 12 staff members and postdoctoral scholars, representing a range of science expertise. The top 8 proposals were given to the STUC for additional review in order to make a recommendation to the Director for a pool of about 1500 targets. After thorough discussion of these proposals, the STUC reached a consensus recommendation for four new programs.
  9. The STUC heard a presentation of preliminary results from STScI’s community survey of attitudes regarding exclusive access periods (EAP) for HST and JWST data. Space Telescope is continuing their analysis of the survey data, and are preparing a full report on the results to be released in several months. The report will be shared with a working group tasked with making a recommendation on exclusive access period policy to the STScI Director. The working group will be composed of members of the current STUC and JSTUC, as well as other community members. The survey included responses from 1171 participants. The survey covered a broad range of questions and collected numerous demographic characteristics. The results showed that respondents felt that both junior and senior scientists working on GO program data would be negatively impacted by zero exclusive access period, while scientists working on projects that use archival data would not, on average, either benefit or be negatively impacted by zero exclusive access period. The STUC recognizes the overwhelming desire of the community represented in the survey to retain the current exclusive access period, and looks forward to the findings of the working group.

That’s it from the Spring 2023 STUC meeting! The STUC will meet again in Fall 2023.

As a reminder, nominations for STUC membership can be submitted at any time by email to Self-nomination is welcome, but not required. Submissions are encouraged, but not required, to include a cover letter and a one-page curriculum vitae summarizing the nominee’s relevant background and HST-related interests. While members must be affiliated with institutions in the U.S. or in ESA countries, there is no restriction on citizenship. Nominations will be considered on a rolling basis, as several members rotate off after every meeting.

As always, please remember that the STUC exists to represent you, the user community for HST. Please don’t hesitate to contact us with any issues or questions you may have relating to Hubble policies, proposing and utilization.


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