What Is APT?
The Astronomer's Proposal Tool (APT) is used to write, validate, and submit proposed and approved observations for the Hubble, Webb, and Roman Space Telescopes. (Note that APT is used to submit proposals for HST and JWST, but there is a separate Roman Telescope Proposal System.)
Download and Installation Instructions
The installers for both Linux and Windows have changed as of APT 2026.3.2. The Linux installer is now a zip file that you unzip. The Windows installer is now a native, signed Windows application installer. There are more details in the platform specific instructions below. (Note that the Roman installers have not changed yet!)
Trouble installing APT? Please see Troubleshooting Tips at the bottom of each of these platform specific Installation instructions.
Current Supported Releases:
| Mission | Supported Version(s) | Release Date(s) |
|---|---|---|
| HST |
2026.5.1 |
9/4/26 |
| JWST |
2026.5.1 |
9/4/26 |
| Roman |
2026.4.2 2026.4.3 |
7/15/26 8/17/26 |
Note that Roman releases of APT are separate from HST/JWST releases. More details in the link below.
Documentation, Training, and Support
Links to user documentation, training materials, and APT support are provided in the sections below based on the type of proposal being submitted.
Roman
- Welcome to APT for Roman
- Roman APT quick start guide
- How is APT different for Roman?
- Roman APT Knowledge Base (FAQ)
- Roman APT Support (Help Desk)
JWST
- JWST APT Overview
- APT Training Examples and Video Tutorials for JWST
- How APT is used in the Proposal Planning Workflow
- JWST APT Knowledge Base (FAQ)
- JWST APT Support (Help Desk)
HST Phase I
- Filling Out the APT Proposal Form
- Training Videos and Documentation for APT's Tools
- Phase I Roadmap
- HST APT Knowledge Base (FAQ)
- HST APT Support (Help Desk)
HST Phase II
- Phase II Proposal Instructions
- Phase II Specific Training Videos and Documentation for APT's Tools
- Phase II Roadmap
- HST APT Knowledge Base (FAQ)