Available Targets

PLATO’s core science focuses on both exoplanets, particularly terrestrial planets in the habitable zones of Sun-like stars, and on asteroseismology, enabling new insights into stellar structure and evolution. The majority of PLATO’s data will become publicly available right after calibration and validation.

To support this core science objective, the PLATO Input Catalog (PIC) has been carefully designed and is continuously curated. It comprises the tPIC (target PIC), scvPIC (science and calibration PIC), cPIC (instrument calibration PIC), and fgPIC (fine‑guidance PIC). The tPIC has been assembled to represent the four mission‑defining P‑samples (P1, P2, P4, P5), and it also contains the important Prime Sample. For full details, please consult the dedicated PLATO Input Catalog (PIC) webpage and all references linked therein, and explore the PIC data via the PLATO ArXiv (PAX).

To maximise the science of the mission further and provide opportunities for complementary science, targets that are not readily covered by these categories but are in the PLATO field can be proposed for Guest Observer (GO) observations. This page summarises which targets are eligible, which are restricted, and under which conditions proposals may be accepted for the 1st Announcement of Opportunity (AO‑1).

Location Requirement

Only targets located within PLATO's first observation field (LOPS2), may be proposed. Objects outside this sky region cannot be proposed for in AO‑1. Target coordinates and visibility can be verified through the proposal software and via the PLATO ArXiv (PAX).

Science Case Requirements

The following tables give an overview of the different possible scenarios. Selected details are further described below. However, users are adviced to carefully consult the Policies & Procedures document for the definitive requirements.

Caveats, for example regarding data proprietarity, may apply in individual cases, as outlined in the Policies & Procedures document. For targets in common to several sub-catalogues, the order of application of criteria is: Prime Sample -> tPIC -> scvPIC/fgPIC -> cPIC. 

Targets That Cannot Be Proposed

Prime Sample

Prime Sample targets are fully reserved for PLATO’s core mission programme. They cannot be proposed under any circumstances or for any science case. Additionally, any source within 120 arcsec (circa 6 pixels) of a Prime Sample target is automatically disallowed.

Core Science on tPIC Targets

The following science cases are not allowed for any tPIC target:

• Exoplanet science
• Core stellar science (stellar physics, asteroseismology)

These topics are covered by PLATO’s core mission goals and are therefore not eligible for GO time, which is designed for complementary science cases.

Targets Allowed Only With Observing-Mode Upgrades

Some targets may be proposed if required for complementary science objectives and only if the observing mode is upgraded beyond what is assigned in the PLATO Input Catalogue (PIC). This can apply in special cases to:

• tPIC targets (not in Prime Sample)
• scvPIC targets
• fgPIC targets

Examples include switching from N‑CAM light curves to imagettes, or requesting observations with the F‑CAMs. Some tPIC targets already use the highest N‑CAM capability and therefore cannot be upgraded.

Additionally, any target within 108 arcsec of a tPIC, scvPIC, or fgPIC star will be flagged for SOC/TAC review to ensure compliance with duplication rules.

Targets That Can Be Freely Proposed

cPIC Targets

cPIC (calibration) targets may be proposed for any science case, including complementary science and exoplanet or core stellar topics.

Objects Not in the PIC

Targets in the LOPS2 field that do not appear in the PIC can be proposed freely.