CHEOPS Guest Observers Programme

20% of science observing time on CHEOPS is made available to the scientific community to conduct investigations of their choice in the form of an ESA-run Guest Observers’ (GO) Programme. Proposals for GO Programme observing time will be solicited through a series of annual Announcements of Opportunity (AOs). In order to allow new targets to also be included in the GO programme at any time during the mission, up to 25% of the open time will be allocated as Discretionary Time (DT), as part of the Discretionary Programme. This will be overseen by ESA, in consultation with the chair of the TAC and the CHEOPS PI.

On this website we provide the links to key information relevant to prospective users of CHEOPS.


Latest news:

The results of AO-2 are now out - details of programmes awarded observing time can be found here.  The next AO (AO-3) is foreseen to come out in November 2021

Observing time on CHEOPS is currently available through the Discretionary Programme - further details of the programme and how to apply can be found here.

It is essential to contact the ESA CHEOPS Project Scientist (see email below) to check the status of your proposed target before submitting a proposal.




In case of questions, please send an email to the ESA CHEOPS Project Scientist, kate dot isaak at, replacing the " dot " and the " at " with a "." and "'@" respectiviely