JWST Proposal Level Information

The Proposal Information form is used to specify high level descriptions of JWST observing programs. The Astronomer’s Proposal Tool (APT) is used to enter this information into the proposal.


 Format definitions...

Purple text indicates the parameter is Limited Access.

Boldface italics type indicates the name of an APT parameter or a value for a parameter.

(warning)Red text indicates restrictions on a parameter.

(red star) Black text indicates an important note.

Brown text indicates notes for the developers.

Green text indicates the name of the parameter used by Commanding.

Items in brackets - <value> - are required values.

Items in square brackets - [<value>] - are optional.

This article includes general information as well as specific fields for the Proposal Information form.

The Three Phases of Single-Stream Processing

It is a goal of the JWST project to streamline the scheduling of accepted proposals as much as possible. The intent is to get data into the hands of the user community as quickly as possible and to enable real data to drive future proposal ideas. To support this goal, the development of the JWST ground system has focused on providing the means for proposers to submit proposals that, if accepted, can flow into a “single stream" scheduling process quickly and efficiently. This is in contrast to the two-phase proposal process that many HST users are familiar with.

The use of observation templates in JWST APT is one important aspect of this strategy. When users select a science instrument and configuration, APT presents the user with only the relevant information and choices, making it much more straightforward to specify observations (and thus proposals). APT and the systems it accesses handles all of the details of breaking observations into visits (if necessary), checking the schedulability of the observations and estimating overheads and total resources needed. Thus, most submitted proposals can be considered complete and, if approved, can move smoothly into the planning and scheduling system.

Clearly there will be exceptions to this strategy. Examples include target of opportunity programs, which simply cannot be fully specified up front in the process, and certain NIRSpec MSA programs for which pre-imaging is required before the details of the spectroscopy can be provided. Proposals needing additional details will of course be accommodated, with inputs accepted from users as they become available. It is expected that these proposals will constitute a small fraction of the overall program of accepted observations in order to minimize impacts to the Long Range Planning activity.

Three phases exist for a proposal in JWST's Single-Stream Processing:

  • The initial phase is the Draft, which is when the proposal is prepared for the Telescope Allocation Committee (TAC).
  • The next phase is Submitted, which is after the proposal is submitted for the TAC to review but prior to acceptance.
  • The last phase is Approved, which is after the TAC process and when the proposal is available to schedule on the telescope.

Note: For more information on any of the parameters discussed in this article, see 2019-11-07_12-44-15_JWST Cycle 1 Proposal Opportunities.

Limited Access Parameters 

The Proposal Parameters articles describe all the parameters available in APT, both individual fields as well as the values of those fields.  Some of these parameters or values are not routinely available to GO proposals, and these are called Limited Access Parameters (LAP). It is possible for a field to be an LAP, or for a particular value or subset of values of a field to be an LAP. In order to access an LAP in a GO proposal, the PI should include a justification for using the LAP in the Observation Description. Once the request is approved, it will be recorded in the operational database, keyed by Program ID.  This will grant specific permission to use a particular field or value.  It will not allow complete access to all LAPs.

Engineering and Calibration proposals will have access to all LAPs by default.

(red star) All LAP parameters/values are indicated by using purple text.

Legal Characters

Proposal text may contain only standard ASCII characters. All other symbols must be spelled out. Greek letters must be spelled out (e.g. BETA-LYR, H-ALPHA). The degree sign should be replaced with “D” (e.g. BD+16D516). Subscripts and superscripts are not allowed.  

Proposal Information

Basic information about the proposal, including the Title, Abstract, CategoryCycle, Scientific Category, Keywords, and Proposal PDF attachment file, is required. Not every item described here must be filled out for every proposal. For example, some items are only relevant for observing proposals, while others are only relevant for archival proposals. APT will automatically indicate which items need to be filled out, depending on which proposal type has been selected. 


This consists of informative text that must not exceed two printed lines in the TAC PDF view of the proposal. (APT will give an error when the title exceeds 150 characters.) The Title should be formatted using mixed upper- and lower-case rather than all capital letters. Quotation marks (") may not be used in the Title. Once the proposal is approved, the title should not be changed. 


This provides an entry field for a concise abstract that describes the proposed investigation, including the main science goals and the justification for requesting observations or funding from JWST. The Abstract must be written in standard ASCII and should be no longer than 20 lines of 72 characters of text. (APT will give an error when the title exceeds 1700 characters.)

Proposal ID

Once the proposal has been submitted, the assigned Proposal ID will be displayed here. 

STScI Edit Number

This is an internal field which is incremented whenever the file is updated by STScI staff.


One of the following categories may be selected:

  • GO - General Observer proposal

  • SURVEY - Survey proposal
  • AR - Archival Research proposal (this category includes the Legacy, Theory, Data Science Software Proposals) 

Proposals for Director’s Discretionary Time submitted outside of the normal review cycles should select:

  • DD - Director's Discretionary Time proposal
    • ERS - Early Release Science proposal

Special categories:

  • GTO - for Guaranteed Time Observers only

The following proposal categories also may be used internal to STScI:

  • NASA - for NASA-sponsored proposals
  • Other: ENG

(There is a separate keyword for the instrument that is used for Calibration and Commissioning proposals; ENG and GTO proposals do not have an instrument keyword.)


This item appears in the APT form only for AR proposals (see Legacy AR proposals).


This item appears in the APT form only for AR proposals (see Theory proposals). 


This item appears in the APT form only for GO and AR proposals (see Calibration GO proposals and Calibration AR proposals ). 

Cloud Computing

Mark this keyword if you are submitting an AR Cloud Computation Studies Proposal. This item appears in the APT form only for AR proposals.


This item appears in the APT form only for GO proposals (see Treasury GO proposals).

Data Science Software 

This item appears in the APT form only for AR proposals (see Community data science software proposals). 

Pure Parallel Proposal

This type of observing proposal contains specifications for observations to be taken as Pure Parallel science observations, as described in JWST Parallels (see Pure parallels) .


For a Cycle 1 proposal, enter 1 (this is the default). Multiple values of Cycle are not permitted.

For Commissioning proposals (COM), the default Cycle of 0

Note for developers: If the proposal category is not COM, then a warning should be issued for Cycle = 0.

Note that the following seven fields do not apply to AR proposals. Archival proposers can skip to down to Scientific Category.

Explain Unschedulable Observations 

Free text field to explain unschedulable observations. This text is not included in the TAC's PDF view. When it is provided errors about unschedulable observations become warnings.

Science Time/Charged Time 

After observations have been created in the proposal, the total amount of Science Time requested in the proposal is displayed here. The Charged Time displayed includes all the overheads.

Data Volume

Displays the total Data Volume in megabytes (MB) for all observations in the proposal. For information on managing data volume, see JWST Data Rate and Data Volume Limits.

Request Custom Time Allocation

Normally the time requested of the TAC is the Charged Time calculated by APT. But in a few cases it will be necessary to request more or less time than is currently reflected in the APT proposal (see Modifying APT time allocation requests).

As with Charged Time, the total Requested Time includes all overheads. The Time Requested Explanation is a free text field to explain why a custom time was requested.

Proposal Size 

There are 3 proposal sizes for GO programs. This size is based on the Charged Time (unless overridden by a Requested Time) plus any time requested for future cycles:

Future Cycles 

Multi cycle proposals should provide a year-by-year breakdown of the time requested in future cycles. This is accomplished by entering information in the Next Cycle box and the Third Cycle box. Alternatively this can be represented as a percentage of the current cycle. If coordinated parallel observations are requested for future cycles, select the corresponding checkbox (an exact time is not required). Note that pure parallel proposals are not permitted to request future cycle observations.

Exclusive Access Period(formerly known as Proprietary Period)

This item appears in the APT form for all categories except AR proposals.

Enter the requested exclusive access period  (see Data rights and duplications)  that will apply to all observations in the proposal; see Table 1 for legal values and default values. Non-default values are noted both in APT and in the TAC PDF view.  Any exclusive access period that is longer than the default value must be justified in the text of the proposal.

Table 1. Legal and Default Exclusive Access Periods


Legal Values (months)

Default Values

GO Small (time≤25 hours)

0, 3, 6, 12


GO Medium (25<time≤75 hours)0, 3, 6, 1212

GO Large (time>75 hours)

0, 3, 6, 12


GO (Treasury)

0, 3, 6, 12



0, 3, 6, 12



0, 3, 6, 12



0, 3, 6, 12



0, 3, 6, 12



0, 3, 6, 12








Allow Restricted 

This checkbox allows the APT user to temporarily (for the current session) see the Limited Access Parameters.

Scientific Category

  • Solar System Astronomy
  • Exoplanets and Exoplanet Formation
  • Stellar Physics and Stellar Types
  • Stellar Populations and the Interstellar Medium
  • Galaxies
  • Intergalactic Medium and the Circumgalactic Medium
  • Supermassive Black Holes and Active Galaxies
  • Large Scale Structure of the Universe

An Alternate Category may also be chosen.

Science Keywords

At least two but no more than five keywords must be entered. These should describe the science goals of the proposal. See JWST Scientific Keywords for possible entries, based on the Scientific Category selected.

Coordinated Telescopes

This appears in the APT form only for GO proposals. If a request for both JWST observing time AND observing time at another observatory is being made, the other observatory must be selected with an accompanying time request.  Observatories include: Chandra, XMM-Newton, NOAO, NRAO, and HST.

(red star) Note that only HST will be available for Cycle 1.

Proposal PDF Attachment

The location on the proposer's computer of the PDF file with the scientific justification that is to be attached to their submission is entered here. This file should contain the items described in the Proposal narrative.   A proposal consists of a completed APT proposal form and an attached scientific justification.

Note for developers: the PDF attachment is permanently exclusive access and should never be made publicly available with the rest of the proposal, even during the transition to an accepted observing proposal.

Proposal Observing Description 

Describe in 1 to 2 paragraphs the observations requested in this proposal, indicating targets, instruments, modes, and any special requirements. This section should provide an overview of the proposed observations for reference by the program coordinators and instrument scientists, who will be reviewing and implementing the observations. This observing description will be publicly available for accepted proposals, unlike the Technical Description of the PDF attachment, which always remains confidential.

Team Expertise and Background

Provide a brief description of the expertise, background, and roles of key team members, as they relate to the science proposed. This section should be limited in length; for most proposals, a paragraph or two will suffice. For proposals with a large number of Co-Investigators, it is not necessary to report on the qualifications of every team member; nor is it necessary to provide a bio of the team members.


Retrieving an Investigator from the proposer database

Investigators must have MyST accounts. Enter the first few letters (at least two) of a name and then use of the Enter or Tab key. This launches a pop-up window that contains a list of matching MyST accounts. When an entry is selected, the APT form will be populated with the information for that investigator.

Adding or updating an Investigator's information

If the individual does not have a MyST account, click OK in the pop-up and enter the information. If the individual is in the database but the information is incorrect, click Update This Address. Either action causes the web page for MyST to appear, so that the individual can be added or information for them can be updated in the database.

Once the information is entered into MyST, a database search on the new individual can be run immediately. If information for an existing individual was updated, the new information should be available within a day.

Principal Investigator (PI)

Each proposal must have a PI. The PI is responsible for the proper conduct of the research, including the appropriate use of funds and the fulfillment of administrative requirements. A Co-Principal Investigator (Co-PI) option is also available, allowing two or more proposers to share the scientific responsibility of the project.   Any other individuals who are actively involved in the proposal should be listed as Co-Investigators (CoIs). For U.S. PIs, the institutional affiliation is defined as the institution that will receive funding if the proposal is approved (see Proposer types and submission eligibility). 

Co-Investigator (CoI)

CoIs can be added in APT as necessary in the submitted proposal; once a proposal is approved, a CoI can be added only with prior approval. By default, APT provides one blank CoI form. Other CoI forms can be added or deleted, as necessary. For U.S. CoIs, the institutional affiliation is defined as the institution that will receive funding if the proposal is approved.

If one of the CoIs (or another individual) is to serve as the contact for a proposal, then the Contact keyword box should be checked. The Contact is the person the Principal Investigator has designated to receive all (non-budgetary) questions/information on the proposal and to be the official voice for the team. More than one CoI may be designated as the Contact. Once designated, only the Contact may make Change Requests in an approved proposal so that conflicting requests are not made.

If a proposal has a non-U.S. PI and one or more U.S. CoIs, then you must mark the US Admin CoI box (in the PI form) for one of the U.S. CoIs.  This indicates which U.S. CoI will be the Administrative PI for overseeing the grant funding for U.S. investigators (see Proposer types and submission eligibility).

Change log

 Click here to expand...

Version 10 (November 18, 2019)

  1. PROPINSTJWST-91426 - updated Science Categories and Keywords.
  2. PROPINSTJWST-91433 - updated Coordinated Telescopes section for HST option.

Version 9 (April 16, 2019)

  1. Editorial change (moved change log to main article)

Version 8 (March 18, 2019)

  1. PROPINSTJWST-91385 - Add Data Volume section to Proposal Level Information article

Version 7 (January 23, 2019)

  1. PROPINSTJWST-91366 - Added Team Entry Field section.
  2. PROPINSTJWST-91367 - Added Cloud Computing section.

Version 6 (April 3, 2018)

  1. Editorial change (fixed bad links)

Version 5 (January 17, 2018)

  1. PR 89718 - added ability to specify coordinated parallels in future cycles

Version 4 (September 7, 2017)

  1. PR 83662 - added Proposal Size field
  2. PR 83662 - updated the proprietary period table
  3. PR 86720 - details for Archival Proposals
  4. PR 88629 - revised text for exclusive access period
  5. PR 86242 - added Co-PI description
  6. PR 87739 - added Survey proposal type

Version 3 (August 24, 2017)

  1. PR 82590 - added note about justification use of LAPs
  2. PR 88443 - added full description of the Observation Description field

Version 2 (January, 20, 2017)

Changed based on feedback from Lou Strolger

Version 1 (October 31, 2016)

This is the converted Word file from Chapter 2 and Appendix A.

  1. Used APT PR 85699 to update the Science Categories and Keywords
  2. PR 86672 - added note about Coordinated observations not applicable to Cycle 1.