Where to start?

Preparing a PLATO Guest Observers (GO) proposal and navigating the wealth of available information may feel complex at first, especially for first‑time proposers. The structured steps outlined below are intended to support an efficient and well‑organised preparation process. This page provides a practical starting point and highlights a few important notes to help avoid common pitfalls.

1. Start with the Policies & Procedures

Your first and most important reference should always be the Policies & Procedures document. It is the definitive source for all proposal requirements and takes precedence over any summaries provided on these webpages. The document describes the PLATO science programme, available observing time, operational constraints, proposal structure, formatting requirements, and the tools used for proposal preparation and submission. Reading it carefully before starting your proposal will save time later and help ensure formal compliance.

Read more: Policies & Procedures

2. Familiarise yourself with the Mission Handbook

This document is the primary reference for scientists preparing PLATO observations. It provides an overview of the spacecraft, payload, observing strategy, operational concepts, and data products. Proposers are encouraged to consult the Mission Handbook early, which is pivotal when designing observing strategies or assessing the suitability of PLATO for their science objectives.

Read more: Mission Handbook

3. Register early for the PLATO GO system

Proposal submission requires both a valid ESA Cosmos account and a registration in the PLATO GO system. Registration should not be left to the final days before the deadline, as important tools and features are only accessible once registration is complete.

Sign up here: Registration

4. Explore targets via the PLATO Input Catalogue (PIC) and the PLATO Archive (PAX)

Target selection is a central part of proposal preparation. Proposers are strongly encouraged to explore the PLATO Input Catalogue (PIC) via the PLATO Archive (PAX) early on. These tools allow you to identify targets in the PLATO field, check restrictions such as Prime Sample membership, assess potential contamination, and retrieve stellar parameters required for feasibility assessment. Dedicated webpages and references therein describe the PIC and PAX in more detail.

Read more: PLATO Input Catalogue (PIC)

Explore here: PLATO Archive (PAX)

5. Begin preparation early, consult the webpage examples and FAQ, and leverage the proposal software

Early preparation is strongly recommended. Support resources are limited close to the deadline, and late questions may not always receive timely responses. Proposers should actively browse the PLATO webpages, in particular the sections dedicated to the proposal submission and FAQ, which provide user‑friendly examples and illustrations of the formal requirements described in the documentation. These pages are intended to complement, not replace, the Policies & Procedures. Make active use of the ESA Science Campaign Handling System (CHS) and the integrated Call for Proposals toolset (CfP), which support target validation, duplication checks, noise‑to‑signal estimates, observation duration assessments, and proposal submission.

Read examples: Proposal Submission & FAQ

Prepare here: Proposal Software

6. Ensure full dual‑anonymity

PLATO proposals are evaluated using a dual‑anonymous peer‑review process. All proposal material must therefore be fully anonymous, including uploaded documents, file names, and any text visible to reviewers. Proposals that do not comply with the dual‑anonymity requirements are automatically rejected on formal grounds. If in doubt, consult the dual‑anonymity guidelines or contact the PLATO Helpdesk before submission.

Read more: Dual-anonymous Guidelines

7. Submit via the official proposal software

All proposals must be submitted through the official proposal software, the ESA Science Campaign Handling System (CHS) and the integrated Call for Proposals toolset (CfP). Submission by email or other means is not possible. Access to the system requires a valid Cosmos login and active GO Programme membership. Only proposals successfully submitted before the deadline will be considered.

Submit here: Proposal Software

Important notes

An award of observing time does not guarantee execution. Operational constraints, scheduling limitations, telemetry considerations, and unforeseen events may affect feasibility, even for high‑priority programmes. PLATO will make every reasonable effort to carry out awarded observations, but adjustments during planning and execution may be required.

Stay informed

Updates, clarifications, and announcements related to the AO Call will be posted at the bottom of this webpage. Proposers are encouraged to check back regularly throughout the Call period.