The Earthnet Programme: 40 years of evolution and future challenges


02 Jul 2020

Initiated in 1976, ESA's Earthnet Programme provided the initial technical and operational means to access and exploit Earth Observation data, while launching and stimulating a scientific Earth Observation user community in Europe.

Today, Earthnet provides access to data from Third Party Missions and it represents the cornerstone of Europe's Earth Observation international cooperation, responding to the always evolving global situation in the EO context.

Since 2016, Earthnet also supports the International Charter on Space and Major Disasters.

Shortly after ESA was established, Member States agreed on creating the Earthnet programme. This was a network for Earth, to stimulate global cooperation between space experts concerning activities aiming to acquire and share knowledge of our planet, for the benefit of all citizens in Europe and beyond.

Back in the 1970s the Internet did not exist yet, therefore, ESA experts were faced with the enormous task of establishing a user community for all data acquired by satellites, with somewhat limited resources and infrastructure available.

At a time that ESA did not yet have missions in operations, the Earthnet Programme served to develop an Earth Observation (EO) user community, comprising a network of international ground stations, PAFS (Processing and Archiving Facilities) and Integrated User Services to support the acquisitions and subsequent exploitation of the ERS satellites.

Earthnet thus also necessitated the creation of a huge decentralised archive of exclusive data, comprising various Landsat and National Oceanic and Atmospheric Administration (NOAA) missions, for the benefit of scientists at a global level. It also involved the production of data processing chains, based on advanced technology solutions, installed worldwide, mainly close to the antenna of the receiving stations.

With interfaces to many national and international Third Party Missions (TPMs), a "National Point of Contact" was thus created, which served as an interface with each country in the programme and the potential users interested in the data. The facilities were coordinated by ESA's ESRIN centre, which provided the first interface with data users. It was the dawn of an era.

In order to help develop the user community, Principal Investigators (PIs) led teams of scientists that studied how best to use all these data, in various applications that could be of good use – from agriculture, climate, sea studies, to desertification, etc. These PIs were the pioneers of the operational applications that we see today in many EO-based services worldwide.

All of these efforts made ESA well-prepared for ERS – ESA's first environmental monitoring programme in Earth observation, which consisted of two satellites launched in 1991 and 1995.

Throughout the years, the Earthnet programme progressively evolved, facilitating the shaping of the global EO context. It has also supported cooperation ensuring a constant international dialogue in all major international EO initiatives and bodies, such as CEOS (Committee on Earth Observation Satellites) and GEO (Group on Earth Observations). Earthnet has funded international projects such as Dragon and Tiger, which today still respectively facilitate cooperation with China and African countries.

Lastly, since 2016 Earthnet also supports the International Charter on Space and Major Disasters.

But who were some of the main players involved in its creation and in that of the TPM Programme?

Meet Mario Albani - Head of Earthnet Operations and Development section from 1980 until 1990, and of Earth Observation Operations division from 1991 till 2005

Mario Albani
Mario Albani

What was the major challenge that you had to overcome while managing Earthnet?

The major challenge was to ensure and manage the financial and technical resources needed to overcome the lack of adequate technology. In the early days, only commercial equipment was available, such as analogue Ampex tape recorders used by TV industry and computers with relatively low power and little memory size in comparison to current standards, resulting in high costs and poor performance in terms of speed and quality. Satellite products at the time were much smaller in size, however, and as an example, a single orbit product from the MOS-1 satellite was 512 Bytes, in comparison to modern satellites, which can be up to several GB in size.

For instance, the processing time for one standard SEASAT SAR scene was 24 hours versus today's few minutes to obtain any specific scene.

So we had to develop digital tape recorders and mission specific hardware and software, based on emerging technologies—not an easy task!

Pascal Gilles
Pascal Gilles

Pascal Gilles, current Head of Ground Segment & Data Management Division, affirms, "When ESA began the Earthnet Programme, it was the start of an era, and everything from processing tools to product formats; from verbal and written communication means, with current and future Users to the use of Internet and e-mails; from operational to quality control processes; from the early stages of highly specialised and centralised super computers, to the more versatile personal computers and work stations; everything had to be invented and set-up without previous experience to rely on.

"This was a continuously evolving process, which contributed to bring some of the most innovative elements to Earth observation over the past decades, paving the way for Earth Observation to be well prepared in order to step in today's Digital society and economy —a great leap in innovation".

Meet Bianca Hoersch - Earthnet TPM Programme Manager from 2004 to 2017

Bianca Hoersch
Bianca Hoersch

What were the key opportunities you managed when leading the Earthnet Third Party Mission programme?

A major opportunity was to enlarge the Third Party Mission portfolio, by diversifying the co-operation schemes. Before 2004, when I took up the TPM scheme, co-operations with international partners generally focused on providing data downlink and repatriation of data, and in return gaining scientific use rights for such data for the European user community. As such schemes were cost intensive, the number of TPMs remained low.

With a new selection and assessment scheme introduced in 2004, which is actually still operated to this date, the TPM team and I were able to increase the diversity of co-operation schemes, not all of them necessarily requiring massive infrastructure build-up on ESA's side, thus in fact more cost-effective, which allowed us to increase the data volumes coming out of TPMs. This was beneficial for the user community, as the portfolio of the TPMs was widened and offered also access for scientific exploitation purposes to commercial missions that were previously unattainable for the science community, due to high cost, while not impacting the core business of the TPM owner.

It was great that we were able to adhere to the 'free and open' access for any TPM user, established since 2010 like for all ESA missions.

Other schemes that made the TPM attractive in particular to National member States, was the possibility to extend mission lifetimes, by providing co-funding that would have otherwise had to be switched off at the end of the mission's nominal life. A wonderful example of this is ODIN, a Swedish-Canadian-Finnish-French atmospheric chemistry mission, similar to ESA's Proba-1 mission, initially built as technology demonstrator for 1 year lifetime that in the end operated close to 20 years thanks to Earthnet TPM, providing incredible time series to the user community.

One of the TPM selection criteria introduced in 2004 was 'complementarity to ESA missions', to gain additional benefit through joint mission exploitation. A perfect example was the selection of gravimetry GRACE mission to complement GOCE. Like this, the TPM scheme was not only a standalone success, but a great contribution to advance ESA's missions of the Earth Observation envelope programme (EOEP).

A constant challenge was that with the limited funding of Earthnet, not all user requests could always be satisfied, in particular those working at large scale requiring wide data coverage across countries, or highly repetitive coverage. So as TPM Mission Manager it was always a challenge to assign the proper data volumes to the most promising user projects, and keep consistency and objectivity.

Personally, the most rewarding aspect for me was the user interaction, and the feedback from workshops and events, which I brought back into the TPM programme.

Last but not least, the concept established with the TPM programme was laying foundations for the co-operation with the European Commission's Copernicus Contributing Missions programme.

Long life for TPMs, as an integral part of the ESA Earth Observation family!

Meet Giuseppe Ottavianelli - Earthnet TPM Programme Manager since 2017

Giuseppe Ottavianelli
Giuseppe Ottavianelli

Where do you think the TPM activities are headed?

It was a great honour to take the relay of this role in 2017. Today, the EO landscape is rapidly changing with many new satellites being launched and with the novel contributions by the NewSpace participants. These assets are fully considered in the evolution of the EO international framework and fall in the perimeter of Earthnet.

In this framework, ESA actively facilitates the possibility to integrate missions into the Earthnet portfolio, enriching its offer towards the R&D community to further promote innovation. Moreover, users have also recently raised the need to strengthen the role of Earthnet as enabler of data interoperability through multi-mission calibration/validation (cal-val) and data quality assessment activities.

This function of Earthnet will be essential to: a) foster synergies across missions and the creation of virtual constellation also with ESA and Copernicus space assets; b) ensure the sustainability of multi-mission cal/val efforts and harmonisation of related protocols (e.g. fiducial reference measurements, instruments cross-comparison exercises, support to cal/val infrastructure); c) build cal/val and data quality expertise and capacity in TPMs operators.

Another fast developing aspect is the need for users to access the data in hosted processing environments, something also very applicable to TPM data. Earthnet has tested these data operational scenarios and users have confirmed the great interest in such flexible approaches. Within its mandate, Earthnet will therefore continue evolving both its approach and technical solutions, always facilitating cooperation and the consolidation of the network for Earth.