ESA Science & Technology - INFO 12-1995: European Space Science Scales New Heights

Satellites, comprising nine tonnes of hardware and sixty experiments, will be placed in orbit with a view to giving scientists a new perspective on the Sun, the Earth's magnetic environment and the universe in general.

ISO, the Infrared Space Observatory, will allow astronomers to study all types of objects in the so1al. system - from nearby planets to the farthermost galaxies - with unparalleled sensitivity through the invisible, cold light of infrared radiation. Soho, the solar observatory, will be the fist satellite to continuously observe the Sun in detail, and will do so for at least two yews.

The quartet of identical Cluster satellites will probe the Earth's magnetosphere in order to study the storms that can occur there which disrupt radio communications or electrical power supplies on Earth.

As Roger Bonnet, Director of the European Space Agency's science programme, points out: "For the programme, this year marks the culmination often years of endeavour now drawing to a close. This shows that Europe is now taking the lead in in situ exploration of the universe".

On 23 May ISO successfully completed final testing which validated the satellite's technical performance. It is currently on its way to Guiana onboard the Ariana. It will be launched from the Space Centre at Kourou by an Ariane 44P launcher in late October.

On 14 June Soho will undergo similar checkouts which should give it a clean bill of health for dispatch to the Kennedy Space Center (Florida). It is scheduled for a launch on 30 October by NASA's Atlas rocket.

Authorisation to dispatch the Cluster quartet to Kourou should be given in late June with a view to a launch at the end of the year on a flagship launcher: the first Ariane-5, which is set to become the most competitive launcher on the world market, Another milestone in space exploration is in the offing: the journey over the Sun's north pole by ESA's Ulysses probe begins this month and will continue through to September. During this phase, Ulysses will have an unprecedented birds'-eye view of the day star's northern reaches. will it find the same anomaly as that observed last year above the south pole? Will the north magnetic pole prove to be as astonishingly inexistent as its southerly counterpart did last summer? The measurements collected during the next three months will be decisive in continuing the global investigation of the star that heats and sustains life on Earth. Moreover, there; could be other surprises in store for solar astrophysicists. For, at their request, ESA and NASA have decided to extend the Ulysses mission by six yews, from 1995 to 2001, so as to allow them to observe the Sun during a period of magnetic activity.

With three new missions - ISO, Soho and Cluster - due to be launched and a fourth - Ulysses - embarking on a critical exploration phase, 1995 marks a crucial stage in the history of European space science. But all this is no mere coincidence. It should rather be seen as the result of a sustained planning effort that started ten years ago and is now coming up to its half-way point. For in 1985, at the request of the scientists themselves, ESA set up a 20-year (1985-2005) programme designed to pave the way for ambitious science missions. In other words, giving Europe the wherewithal to play its proper part in peaceful exploration of the universe.

The Horizon 2000 plan was devised solely according to certain key criteria: scientific excellence, project coherence, balance, technological content and realistic budgeting. Management efficiency in particular has allowed Horizon 2000 today to work to a budget of ECU 343 million (12.8% of ESA's general budget), equivalent in terms of purchasing power to European space science funding twenty-five yews ago. The missions comprising Horizon 2000 were proposed by the scientific community and then selected by groups of leading research scientists. They include qualified beacon projects, Cornerstone missions, costing the equivalent of about two years' budget and medium-size projects accounting for one years budget.

It is on the basis of the Horizon 2000 programme that Europe has: launched the Giotto probe, which successfully encountered Comets Halley (1986) and Grigg-Skjellerup (1992); developed the Hipparcos satellite, whose catalogue of 120 000 stars will be published in late 1996; built the Ulysses probe, which has been exploring the third dimension of the solar system since 1992; and contributed at a rate of 20% to the Hubble Space Telescope programme.

It is thanks to Horizon 2000 that Europe is now preparing to launch ISO, Soho and Cluster.

It is on the basis of the same long-term plan that Europe will build: Huygens, the probe to be launched in 1997, in co-operation with the United States, to explore the organic planet Titan; XMM, the X-ray telescope scheduled for a launch in 1999; INTEGRAL, the gamma-ray observatory due to be launched in 2001 in co-operation with Russia; Rosetta, the probe which is to land on Comet Wirtanen in 2012; and FIRST, the submillimetre telescope planned to be in orbit in 2006.

After a long and fruitful apprenticeship, European space science therefore now looks set to come into its own. It currently ranks an honourable second place in the world and regularly leads the way in certain specific areas of exploration. Thus Europe is now at the forefront of cometary exploration, fundamental astronomy or "astrometry", solar physics and the physics of interplanetary plasma. So it should also be able to take the lead in infrared astronomy, high- energy astronomy and planetary exploration while continuing to conduct cometary studies with Rosetta.

One remarkable fact is that the approach and success of Horizon 2000 have attracted unanimous praise both in and beyond Europe. The programme is being supported by virtually all Europe's scien1ilsts. It is drawing on and inspiring increasing numbers of scientists, including many of the younger generation. Its content and management have been approved by all ESA's Member States. Outside Europe, the stability and solidity of Horizon 2000 have made ESA an extremely credible and reliable partner, arousing ever greater interest in international - including transatlantic - co-operation.

Given that the first results look positive, it makes sense to think about continuing the work done to date. Which is why this year, half-way through Horizon 2000, it is time to look ahead to the next twenty-year period and embark on the follow-up programme which will lead to further missions being carried out between 2006 and 2016.

At ESA Council meeting to be held in October in Toulouse, European ministers responsible for space will therefore have to take a decision on a Horizon 2000 Plus programme designed to ensure successful European space science over a further ten-year period. The proposal being put forward by ESA's directorate of scientific programmes involves setting up three large-scale missions:

• A mission to explore Mercury, the least known of the inner solar planets, 60iln of whose surface has yet to be mapped
• An interferometry observatory designed to map the sky a hundred times more accurately than the Hipparcos satellite
• A gravitational observatory able to pick up the space time waves emitted by the universe at the precise moment of the Big Bang.

In parallel four medium-size missions - their content still to be defined - would be carried out.

As with its forerunner, Horizon 2000 Plus has been defined on the basis of proposals submitted by the scientific community following open competition. In all, 110 mission concepts were proposed by a total of 2500 scientists. These were then examined by peer-review groups, involving 75 scientists in all who announced their final choice on 1 October 1994.

The agency is proposing to start preparing for Horizon 2000 Plus on the basis of level funding up to the year 2000. This means that ESA would undertake to conduct preliminary Horizon 2000 Plus technological studies by drawing on the Horizon 2000 budget, even though this, was not initially planned and despite the increased demands of the new missions.

The Horizon 2000 Plus proposals also include an extremely ambitious fundamental physics project - gravitational antenna - not originally covered by the European space science programme. Consequently, putting this Cornerstone mission in place could lead to a modest 5% increase in the annual budgets being requested over the period 2001-2005.

The European space science programme is part of the driving force for industrial technology, fundamental knowledge and European policy generally. Ten years ago, its development was managed in successive stages without a long-term framework, thus ruling out ambitious projects. Today, the European space science community is working to a 20-year plan which has given it its second-place world ranking and prompted regular breakthroughs in hitherto uncharted areas of advanced technology. The task now is to continue down that road with ever greater rigour, professionalism, stability and effectiveness in order to emulate the programme's current success.

Note for TV editors

A betacam tape with new video material on ISO, SOHO and CLUSTER is available upon request. To get a copy please contact the ESA Public Relations Division in Paris (Tel: +33 (0)1 53 69 71 55 - Fax: + 33 (0)1 53 69 76 90)