Our survey of the origins of ESA’s Science Programme reaches the 1980s and a new era with the opening of what we have dubbed the ‘Green Book’. This successor to the 1960s Blue Book (containing the original European plan for science) laid the groundwork for ESA’s first long-term Science Programme, Horizon 2000, and represents a new generation of strategy for space science at the outset of a fresh decade.
Published in December 1978 as ESA SP-1015, Recommendations on the development of space science in the 1980s was authored by the ESA Science Advisory Committee (SAC). Several members of the SAC are credited as the writers of the report, including its Chairman, Professor Roger Bonnet, who would be on to become instrumental in its implementation as ESA’s second Director of Scientific Programmes from 1983.
However, as its preface (Historical Background) explains, the report was the outcome of work on a long-term policy programme for scientific activities that actually began in 1975, during the formation of ESA. So, while it notes that similar exercises had been undertaken by ESA’s forerunner ESRO (the European Space Research Organisation) in 1970 and 1974, this was the first attempt to elaborate such a programme for ESA, following extensive consultation with the European scientific community.
Setting the scene
Accordingly, its introductory chapters credit ESRO with leading Europe from the sidelines to being recognised as a valuable contributor to space science, before making its case from the very beginning for increased funding of the ESA science budget, a theme which goes on to be reiterated throughout the report.
They go on to trace the increasing complexity and cooperation of missions through the ESRO years, before looking to the future and how space science could be developed within ESA during the 1980s – a subject made equally fascinating for today’s readers with the benefit of several decades of hindsight! Building on the European impact outlined within their text, the authors conclude with a recommendation to “exploit those fields of science of which the originality is well recognised, and which can be undertaken earlier in Europe that in the USA or USSR”.
Proposals, partners and technology
Chapters four to six form the heart of the report, making recommendations, considering ways of implementing them, and exploring the directions in which technical resources should be oriented.
Chapter four lays out summaries of the future plans of the four ESA scientific working groups, on Astronomy, the Solar System, Life Sciences and Material Sciences. It then goes on to look at size distribution and event rate, where the authors are concerned to maintain hard-earned European competitiveness and to meet the requirements of frequency and brilliance in projects.
This is followed by five pages of recommendations for a science programme, encompassing larger and smaller satellites or free-flyers and using Spacelab.
The next chapter covers the institutional mechanisms for implementation (as mandatory, optional, or internationalised national programmes), outlines the selection process for programmes and analyses roles and relationships. This last section raises issues with Spacelab and Ariane, largely that Spacelab had not lived up to the expectation of cheap access to space and that double launches of Ariane would be limiting, and stresses that the choice of future missions should not be constrained by their use.
It also offers a perspective on the collaborative environment of the early 1980s, underlining the importance of relationships with NASA and European institutions, particularly in the context of the low funding for the mandatory programme, while noting the dangers of gradual loss of independence with overreliance on partners. The report also discusses the significance of instrumentation development in the recovery of better data to feed scientific discovery and highlights ESA’s prime role in offering flight opportunities for instruments developed by national institutes.
Chapter six, on technical resources, picks up on the theme of Ariane and Spacelab and makes recommendations to improve their adaption to the financial circumstances of the proposed science programme. These include, for Ariane, comparative studies for a fourth stage or re-ignition capability for missions to planets, comets, asteroids, and for Spacelab, extended flights and modified management of the Spacelab utilisation programme to allow shorter lead times. It concludes with a more general statement in favour of research on reusable spacecraft and systems and a proposal to enhance ESA’s Technological Research Programme. The request for a proposed programme of technological developments of interest to the scientific community and relevant to the planned projects leading on from the SAC acknowledgment that “future progress in most fields of space science will depend on the capabilities of devices or systems not yet developed”.
Wrapping up
All these recommendations are brought together in the summary provided in Chapter seven. It also lists the projects in solar-system science and astronomy where “all efforts be made to provide funding”, including a GRIST for solar physics, cometary rendezvous satellite with NASA, Lunar polar orbiter, EXUV and Astrometry satellites. What happened to them? More research will be needed to establish whether elements of these projects were eventually taken into future missions.
In addition to the insights it gives readers into the scientific landscape of almost 50 years ago, and contemporary predictions of the future, this report is an important intermediate chapter in the timeline of European space science. It builds on the inheritance from ESRO and its original ‘Blue Book’ eight-year plan for science, marks the outset of the Bonnet era, and provided the foundations for the Horizon 2000 programme, upon which many of today’s programmes and achievements rest.
Published at the other end of his career and opened in the Archives SHIP database in March 2026, Space Science and The Long-Term Future of Space in Europe, outlines Roger Bonnet’s long association with European science, from the ESRO Astronomy Working Group in the 1960s to his Chairmanship of the ESA SAC from 1977 to 1979 and nearly two decades as Director of Science. The proceedings also remind us that he was involved in ESA’s participation in the Hubble Space Telescope project, Ulysses, Giotto and Hipparcos and was present as Director of Science elect when the selection of the Infrared Space Observatory (ISO) was recommended. (See ESA SP-431.)
Like its predecessor, this ‘Green Book’ shares elements of blue-sky thinking in its aspirations and was not intended as an operational programme. But neither was it conceived to remain at an abstract level; rather, it provides the rationale and conceptual framework for the elaboration of the long-term strategy that would follow, some years later, in Horizon 2000.
More reading
The Green Book in SHIP
Roger Bonnet and Horizon in the ESA Archives space glossary