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Hubble Space Telescope
What's New for Cycle 25 Phase II

This Cycle 25 release of APT contains the following change you should be aware of for Phase II Programs:

  1. Changes in STIS WAVECAL rules - WAVECAL=NO is a SUPPORTED optional parameter starting in Cycle 25. Users who wish to turn off the automatic wavecals can now do so manually within APT without prior authorization from the instrument Team. Additional information regarding this change and its implications for setting up successful observations can be found in the Phase II Proposal Instructions.
  2. Changes to support new COS/FUV restrictions on the use of the G130M grating with segment B at the new lifetime position (LP4) - As described in the Phase II Proposal Instructions (P2PI), there have been significant changes to COS/FUV G130M operations to support the new COS2025 restrictions at LP4. APT supports all of these changes, including a new G130M/1223 setting, restrictions on the use of the FUVB segment with the G130M grating at LP4 for the 1291,1222,1223 central wavelengths in SUPPORTED mode, and the possibility of using FUVB segment with G130M/1300,1309,1318,1327 central wavelengths at LP3 in AVAILABLE mode. Additional details on these changes are available in Section 12.1 of the P2PI, and on the COS2025 webpage.