CHEOPS Discretionary programme



Last update 1 July 2021

The requirement for the target of a discretionary programme to be either newly discovered or newly determined to be of high scientific interest since the close of the last AO (ie. 1 December 2020) is waived for proposals led by PhD students (as part of their PhD work) and/or early career researchers. 

The webpage and documentation for the discretionary component of the CHEOPS Guest Observers Programme are in the process of being updated to reflect this and other recent changes. It is therefore important that prospective applicants check the updates detailed AT THIS LINK before submitting a proposal.


This webpage provides prospective users of CHEOPS with all information (policies and procedures for the programme, documentation, tools and links)  required to prepare and submit proposals to the CHEOPS Discretionary Pragmme, through which 5% of the nominal science observing observing time on CHEOPS will be allocated.

To be eligible for the Discretionary Programme a proposal must meet the following criteria:

  • Contain a single target of high scientific interest
  • Demonstrate that the target was either (a) discovered, or (b) declared to be of high scientific interest since the close of the previous call (1 December 2020)
  • Contain a target/event that is observable by the date foreseen for the end of AO cycle 3 (March 25 2023), and that is not on the CHEOPS Reserverd Target List

Details regarding what needs to be included in a proposal, together with the tools and documentation to support proposal preparation and submission, can be found in the Policies and Procedures document for the Discretionary Programme. Prospective observers are STRONGLY RECOMMENDED to read very carefully through this document.

Important Notes:

In case of questions, please send an email to,  or kate dot isaak at, replacing the " dot " by "." and " at " by "@".




Tools and supporting manuals:


Useful presentations, reference data and links    


User-contributed tools/aids:

Below is a list of tools that have been developed by members of the CHEOPS Science Team for their own use. These have been made available "as-is" via the links below, with caveats and warnings that are detailed in the individual pages