Changes to APT Since the Release of the Cycle 1 Call for Proposals

APT version 2020.1.1, was released in January 2020, and a patch release, APT 2020.1.2 was released in February in support of preliminary work toward the JWST cycle 1 call for proposals. However, during the extended open proposal period, additional APT releases have continued.  A number of significant updates were made for APT 2020.2, which was released to the community on March 10, 2020.  Then two additional APT releases have occurred as part of ongoing maintenance and development activities, with relatively minor functional changes for JWST proposers:  APT 2020.3 was released June 9, 2020 and APT 2020.4 was released Sept. 8, 2020.  Unless any bug fixes are required, APT 2020.4 is the last APT change expected prior to the Cycle 1 proposal deadline.  This article lists the changes of most interest to the user community. 

Due to the extended open period for the Cycle 1  Call for Proposals, proposers should use the latest version of APT to submit proposals for JWST Cycle 1 unless directed otherwise in official announcements from STScI.

Changes of significant interest to proposers that occurred in APT 2020.2 compared to earlier releases are listed below:

  • Overhead/Timing Changes: Additional work has occurred to improve the fidelity of overheads. APT 2020.2 may now report less "Charged Time" than in previous versions due to improved estimates of Small Angle Maneuvers (SAMs).  For example, the overhead for a 20" SAM will decrease from ~86 seconds to ~60 seconds to reflect two efficiency enhancements that will be implemented before Cycle 1 observing begins.  Observations that include many dithers or other small motions thus may see a significant decrease in charged time.

  • Changes to names of Visit Planner constraints: If you need to examine the individual constraints reported in the APT Visit Planner you will find that the constraint names and order have changed to be more readily understandable and consistent with special requirement nomenclature.  For more details, see the related Knowledge article in the JWST Help Desk.

  • Minor Changes in Graphical Timeline: Close examination of the APT Graphical Timeline compared with the previous version may show small changes in the way overheads are reported even if the total amount has not changed.

  • A New NIRCam WFSS Dither: A 2-point subpixel dither pattern has been added to the NIRCam WFSS template.

  • New NIRISS WFSS Dithers: 

    • Filter-dependent dithers have been implemented for the NIRISS WFSS template when GRISM=BOTH.

    • Optional 3-point “Direct Imaging” dithers have been implemented for the NIRISS WFSS template.

  • New Keywords: Debris Disks and Circumstellar Disks have been added to appropriate Science Keyword lists.


APT v2020.3 was released on June 9, 2020. APT 2020.3 contains the following changes you should be aware of for JWST:

  • Review manually created MOS observations:  You can now send a manually created MOS observation to the MSA Planning Tool (MPT) for review in the Plans pane. Click the "Review in MPT" button in the observation and then go to MPT in the toolbar.
  • Timing changes: Minor timing changes (such as in dither patterns) have been introduced through resource file updates and so small changes may be seen by some users.

  • Upgrade to Java 11: APT contains its own Java library. It was updated in the HST release APT 2020.2.1 and so JWST users may see this for the first time with APT 2020.3. It should be noted for people who were getting security warnings about the previous Java. 

As of Sept. 8, 2020, APT v2020.4 has been released. APT version 2020.4 must be used to submit all proposals for JWST Cycle 1 unless directed otherwise by an official announcement. See APT 2020.4 release notes for information on the updates in this version.




Latest updates

  •  
    Added information for APT 2020.4 release.

  •  
    Added language about further updates to APT beyond version 2020.2, and note about APT 2020.3 release.

  •  
    Article updated with the release of APT 2020.2 to reflect actual changes that were implemented.

  •  
    Significant new timing reduction for SAMs added.


  • APT 2020.2 release date updated to current expectation.

  •   
    Small correction to text of 2nd bullet.

Originally published