Purpose
In addition to providing users with data from its own Earth observing satellites – the ERS-1&2 and Envisat missions, the Earth Explorers and in future the GMES Sentinels – the European Space Agency (ESA) has long provided users with access to a number of non-ESA missions, so-called ‘Third Party Missions’ (TPM). The purpose of this document is to help users identify the various types of data that are available from these Missions, the kinds of applications that the data may be used for, and, importantly, the practical procedures required for access - including registration, search, selection and retrieval of the data of interest.

Scope
ESA’s TPM scheme, funded under ESA’s Earthnet activity, has operated for more than 30 years - providing EO (Earth Observation) data from non-ESA/non-European missions to mainly European users. This reflects the needs of the majority of European users who rely on a combination of EO data, both to increase sustainability of their service and to complement the range of observation parameters.

• that is operated by any legal body, governmental or non-governmental entity other than ESA;


• for which ESA assumes some formal responsibility towards the mission operator or to which ESA contributes financially, usually through sharing of Ground Segment facilities or operations; or


• for which ESA assumes a data distribution responsibility to a European or worldwide user community.

The TPM scheme currently includes over 50 instruments on more than 30 missions – covering historical, current and potential missions. A list of missions currently included in the TPM scheme can be found at:
http://eopi.esa.int/TPM
http://earth.esa.int/missions/thirdpartymission.

The benefits of individual TPMs are reviewed as part of the EO data portfolio on an annual basis. The review includes identification of missions - proposed either by ESA, by ESA Member States or through User Projects - as potential ESA TPM candidates. A technical and scientific evaluation is performed, including review by the ESAC (Earth Science Advisory Committee), taking into consideration the mission characteristics, the type of data to be provided by the mission, as well as complementarily to both ESA and other TPMs. Emphasis is given to the potential for use in a scientific context and pre-operational applications.

• serving ESA Member and Associates States user community;


• serving users for scientific/research purposes; and


• data acquisition/geographic coverage mainly over Europe, supported primarily by European acquisition stations.

In recent years, evolving user requirements and a growing user community have broadened the geographic extent covered. Today, the TPM scheme also covers regions outside Europe, in some cases with worldwide coverage, and serving non-European users (e.g. African, Asian, etc.). Furthermore improvements in technology have lead to an evolution in access mechanisms no longer necessarily linked only to direct transmission to European ground stations.

As more and more EO applications have evolved and are reaching maturity, the users of the TPM scheme have expanded thematically beyond pure research to include application development and pre-operational use - including those funded by ESA’s programmes such as DUE (Data User Element), EOMD (Earth Observation Market Development) and GSE (GMES Service Element) related activities.

The reader should note that operational GMES data access is out of the scope of this document. More information on GMES can be found here:
http://www.esa.int/gmes.

Contents and How to Use this Document
Section 2 contains commonly used acronyms and includes an index of ESA supported EO TPMs.

Section 3 explains ESA’s overall data policy, the process to order and obtain data.

Section 4 helps users to understand and select data from the various types available. Available data are categorised to aid selection, and a summary of available coverage – both spatial and temporal – is given. Expert users could proceed directly to Section 5 to focus on the required data. Less advanced users can make use of section 4 and of the ESA online resources (http://earth.esa.int) to develop their understanding of the potential of the various data types.

Section 5 explains the various methods available for accessing the required data including use of the unified multi-mission catalogue (EOLi) for all ESA missions and for most TPMs.

Section 6 contains information on the EOHelp team, and on how to get assistance for accessing and using TPM products.

Having established the steps to register (Section 3); identified the data needed to meet user requirements (Section 4); understood how to access the data (Section 5); Section 7 provides amore in-depth explanation of the data product characteristics for each TPM instrument, and any special conditions regarding coverage or availability.

More information can be found on the EOPI website:
http://eopi.esa.int

The online guide includes hyperlinks to information sources and references to assist with TPM data access.