The Space Telescope Science Institute (STScI) is offering a special Hubble Space Telescope (HST) observing opportunity to the astronomy community to propose for "Bridge Programs" with ACS/WFC and WFC3/IR, in anticipation of likely operational changes in Cycle 33. Those changes are driven by the expanding gap between operating costs and funding levels, and subsequent NASA direction to reduce operating costs for HST relative to FY2023/2024 by ~10% in FY2025 and >20% in FY2026 and beyond. STScI and NASA are working to preserve Hubble’s unique capabilities, critical mission operations, and support for HST's users, but this funding scenario will result in significant impacts going forward. Specifically, we anticipate not offering ACS/WFC and WFC3/IR for new programs in the Cycle 33 Call for Proposals as well as a ramp-down in science operations support for these instruments after Cycle 32.

Given those circumstances, STScI and NASA are providing the community with a limited opportunity to propose for observations with HST ACS/WFC, WFC3-IR and JWST that will contribute to an orderly transition of science programs from ACS/WFC and WFC3-IR to other instruments on HST and JWST.

Proposals for “Bridge programs” must meet one of the following selection criteria:

• The science goals can only be achieved through observations with ACS/WFC or WFC3-IR; e.g., the source is too bright to allow infrared observations with JWST, or the observations require a technical capability (filter, mode) that is only available with ACS/WFC or WFC3-IR.
• The proposed observations will contribute significantly to transitioning science programs or areas from ACS/WFC or WFC3-IR to other instruments. These might include, for example, cross-calibration measurements.

Proposals should be submitted as Cycle 32 GO programs using the Astronomer’s Proposal Tool (APT) by Thursday 7 November 2024 at 8p Eastern (5p Pacific).

Full details on the proposal requirements are included in the Cycle 32 Bridge Program Call.