The first test flight of the new Ariane-5 launcher ended in failure in Kourou, French Guiana, on 4 June, with the explosion of the vehicle shortly after lift-off. The four Cluster scientific spacecraft that made up the payload were lost in the explosion.
This was the first proving flight of an entirely new vehicle with engines ten times more powerful than those of the current Ariane-4 series. The many qualification reviews and ground tests conducted throughout the ten-year development programme have involved extremely rigorous checks on the correctness of all the engineering choices made. Unfortunately, however, there is no absolute guarantee of success at the first attempt with such a complex system.
Nominal ignition of Ariane-5's Vulcain engine at 09.33.59 hrs Kourou time was followed by correct ignition of the solid-booster stages and lift-off 7.5 s later. For the next 30 s of the flight, guidance and trajectory were normal, with the launcher reaching Mach 0.7 (857 km/h) and an altitude of 3500 m. Telemetry data show that immediately thereafter, the nozzles of both of the solid boosters suddenly swivelled to their limit, causing the vehicle to tilt sharply and thereby giving rise to excessive aerodynamic loading and breakage of its structure. This loss of launcher integrity was followed by the destruction of all launcher elements by the onboard safety system.
Preliminary analysis of the telemetry data confirms that Ariane-5's solid boosters and cryogenic main stage functioned correctly during the flight, and the launcher's 'electrical and software system' is presently under scrutiny.
An independent Inquiry Board is being set up by ESA and CNES which will report its findings by mid-July and propose corrective measures to prevent any repetition of this extremely unfortunate accident.
The fact that the launcher's performance was completely nominal during the critical first half minute of flight, and the skills and determination to succeed on the part of all those involved at CNES, at ESA and in European Industry provide every confidence that the second proving flight, scheduled to take place later this year, will be a complete success.
The Inquiry Board's findings and the latest programme status will be reported in the next issue of the ESA Bulletin (No. 87) in August.
ESA astronaut Thomas Reiter recently returned from his record- breaking mission aboard the Russian space station Mir. At 180 days, he has become the non-Russian astronaut to have spent the longest time in orbit.
ESA Astronaut Thomas Reiter (bottom left) with his Russian
crewmates
EuroMir 95, a joint ESA Russian Space Agency mission, ended on 29 February when the Soyuz TM-22 capsule carrying Reiter and his two Russian colleagues landed in the steppes of Kazakhstan. They had been orbiting the Earth aboard Mir since early September 1995. They left behind their two-man, Russian relief crew. The NASA astronaut Shannon Lucid has since joined that crew, remaining aboard Mir after a Space Shuttle docking in March.
During his stay, Reiter performed two 'space walks'. During the first of these, he attached a European experiment to the exterior of the Spektr module. It exposed materials to space and collected space debris and cosmic dust. On the second walk, he retrieved two of the experiment's cassettes, which are currently being analysed back on Earth.
In April, Thomas Reiter was awarded the 'Order of Friendship Medal' by Russian President Boris Yeltsin, in recognition of his 180-day flight. His two crewmates on the EuroMir 95 flight, Commander Yuri Gidzenko and First Engineer Sergei Avdeev, and about 30 other eminent persons from the space community, received similar decorations in a ceremony at the Kremlin in Moscow on 12 April 1996. This day is celebrated as 'Cosmonaut's Day' in Russia, marking the anniversary of the first manned space flight by Yuri Gagarin. The same award had been presented previously to ESA's EuroMir 94 Astronauts Ulf Merbold and Pedro Duque.
Russian President Boris Yeltsin, in discussion with Mr Feustel-Büechl (right) and Dr Andresen
Thomas Reiter was accompanied at the ceremony by ESA's Director of Manned Spaceflight and Microgravity, Mr Jeorg Feustel-Büechl, by the Euromir Programme Manager, Dr. Dieter Andresen, and by the Head of ESA Permanent Mission in Russia, Mr Alain Fournier-Sicre.
During the ceremony, Mr Reiter delivered a well-received message of thanks in Russian to the assembled gathering. Later, Mr Feustel-Büechl was given the opportunity to address President Yeltsin directly on behalf of ESA. After thanking Mr Yeltsin for the honour bestowed on the ESA Astronaut, Mr Feustel- Büechl referred to the joint ESA - Russian mission which had just come to an end: 'We are very proud of this great success, which was the longest mission an ESA astronaut has ever undertaken, and we have particularly appreciated the friendly and cooperative atmosphere in which this enterprise has been performed at all levels. This peaceful cooperation with Russia as a great space nation was a splendid and exciting experience for us, and I an sure that we will have many more opportunities to develop our future cooperation in space', he said.
Figure 1. Temperature levels in the Sun's atmosphere, recorded
with SOHO's Extreme Ultraviolet Imager (EIT) instrument
After less than one month of full operation, and five months since its launch on 2 December 1995, ESA's Solar and Heliospheric Observatory, SOHO, has begun to provide remarkable data that could finally lead to the unravelling of the Sun's mysteries. The first results are all the more impressive because SOHO arrived at its vantage point 1 500 000 km out in space only in February, and commissioning was formally completed as recently as 16 April.
SOHO's payload of twelve scientific instruments includes an extreme ultraviolet imaging telescope, two ultraviolet spectrometers and an ultraviolet coronagraph (an imager for the outer atmosphere) which are being used to study the Sun layer by layer, from its deep interior to the far reaches of the solar wind, over a wide range of wavelengths.
The Sun is currently in the very quietest phase of its eleven- year cycle of activity and appears very calm to those studying it from ground-based observatories. Unencumbered by the masking effects the Earth's atmosphere, SOHO's instruments show that this supposedly quiet Sun is in fact belching out huge volumes of gas into space. They have also detected currents of gas flowing just beneath the Sun's visible surface, and mapped a hole burnt by the solar wind in a stream of gas coming from the stars.
The observations being made in this 'quiet' phase of the solar cycle, when sunspots are scarce, will provide an excellent baseline for SOHO's later investigations during stormier and more confused periods of solar activity. These will occur around the year 2000, as the Sun enters its phase of maximum activity, with a dramatic increase in the number of sunspots and huge explosions becoming commonplace.
'Everyone is impressed by SOHO's performance', confirms Dr Roger Bonnet, Director of ESA's Scientific Programme; 'By the end of this mission, we will know the Sun far better than we do now. Then we will understand the stars better too, because the Sun is the star we see with greatest clarity. Also, we will be able to comment with much more confidence on those important but puzzling aspects of solar behaviour that affect our lives on Earth, whether in terms of short-lived magnetic storms or long-lasting changes of climate'.
The next issue of ESA Bulletin (No. 87, August 1996) will contain a special article devoted to the early scientific results from SOHO, written by the ESA SOHO Project Scientist Dr Vicente Domingo and his colleagues.
Esa's European Land Mobile Services (EMS) payload, which will provide a variety of L-band satellite principally to mobile users throughout Europe and northern Africa, will now be launched on the Italsat-F2 satellite developed by the Italian Space Agency (ASI).
After its launch and commissioning, EMS's capacity will be leased by ESA to Nuova Telespazio, which will serve both as a wholesaler of that capacity to third-party service providers and as a service provider in its own right.
This high-performance communications payload, developed under ESA contract by Alenia Spazio, will allow users with small portable terminals or vehicle-mounted terminals to have access to communications at very reasonable costs. It will be the beginning of a service that will carry on well into the next century. Follow-on payloads, for which ESA is now developing the technology, will be used to provide that continuity of service.
The EMS payload will be orbited as a passenger on Italsat-F2, which is scheduled for launch by Ariane this summer. After the launch and commissioning of the payload, Nuova Telespazio will assume responsibility. It will market services including voice, data and facsimile communications to and from mobile terminals mounted on cars and trucks. The Italsat satellite will complement the services available from terrestrial cellular systems and provide a number of additional types of service. The coverage area will be Greater Europe, extending to North Africa and the Middle East.
Andrea Pucci (left), Chief Executive Officer of Nuova
Telespazio, and René Collette, Director of ESA's
Telecommunications Programme, signing the contract providing for
the lease of EMS capacity to Nuova Telespazio
Prince Willem Alexander of The Netherlands and Prince Phillip of Belgium visited the world-class spacecraft testing facilities at ESA's Space Research and Technology Centre, ESTEC, in The Netherlands, in February.
From left to right: Marius lèfevre, Director of ESTEC, Prince Willem Alexander, Prince Philip and Peter Brinkmann, Head of ESTEC's Testing Division
ESA astronauts Claude Nicollier and Maurizio Cheli returned weary but satisfied on 9 March from their almost 16-day-long mission aboard the Space Shuttle 'Columbia' (STS-75). It had proven to be an eventful one, with the main payload malfunctioning and the mission being extended by two days.
Maurizio Cheli
Claude Nicoller
During the first part of the mission, a satellite was deployed on the end of a 20.7 km-long conductive tether, just 2.54 mm thick. This tether, which generates high voltages, was successfully unreeled to a length of 19.7 km over a period of nearly five hours, but then suddenly broke. The satellite was flung into a higher orbit, dragging the broken tether which was more than 19 km long below it. After much evaluation, it was decided not to try to retrieve the satellite. The reason for the break is still under investigation.
Despite the brevity of the experiment, more data than had been expected was collected. The experiment was able to prove that tethers could be used to generate electricity and to place satellites into a higher orbit. Electricity flowed between the satellite and the Shuttle as the conductive tether passed through the Earth's magnetic field lines. Shortly before the break, scientists reported that the tether was generating a voltage of 3500 V and a current of 480 mA.
Mission management was also able to set up ground stations to communicate with the satellite, within hours, thereby creating a new mission. Three-days' worth of data was collected from the experiments onboard the satellite before its battery ran out (unlike larger satellites, it did not have solar panels).
There are currently no further missions planned for tethered satellites, although their potential for the International Space Station is being considered.
ESA mission specialists Nicollier and Cheli played important roles during the deployment. Nicollier served as the satellite 'navigator', keeping a close watch on its position and movements. Cheli, meanwhile, operated a laser range-finder to accurately gauge the distance of the satellite from the Shuttle.
The mission marked the first time that two ESA astronauts had flown together. A third European, Umberto Guidoni of the Italian Space Agency, was also part of the seven-member crew.
The number of nations and organisations make use of space continues to grow and space debris issue is becoming increasingly urgent. Space debris, however, is a global problem and thus global cooperation in addressing the issue is essential.
ESA is a founding member of one organisation that is addressing the problem, the Inter-Agency Space Debris Coordination Committee (IADC). The group's main purpose is to exchange information on space-debris research between member space agencies and to identify debris mitigation options and promote their application. The other founding members NASA, the Russian Space Agency (RKA) the Japanese Space Agency. The Chinese National Space Administration joined the group 1995.
At the IADC's most recent meeting, another three members CNES (France), BNSC (UK) and ISRO (India) were admitted, bringing the total number of members to eight. That meeting, the IADC's 13th, was held at ESOC in late February with approximately 65 participants in attendance. As a result, several joint activities are being pursued to improve the knowledge of the debris environment in low Earth orbit and the geostationary orbit. The group will also prepare a common database of all space objects. One option is to prepare an extended version of ESOC's current DISCOS database as a preliminary step.
The International Space University (ISU) is continuing to expand. It now offers two professional development programmes: the original Summer Session and a new Master of Space Studies programme. It has also recently added a continuing education programme, offering short courses or workshops on topical subjects.
These programmes are designed to respond to the educational needs and the increasing and evolving demands of the space sector in a rapidly changing world.
Summer Sessions
The Summer Session is
held annually. It is an intensive 10-week programme that covers
many space-related disciplines, taught from an international
point of view. It is held at a different educational or research
institute each year.
The Summer Sessions have been offered since 1988 and some 1000 alumni from 60 countries are now working around the world. Students have included Jim Newman (Class of 1989), now a NASA astronaut, who flew on the STS-51 mission in 1993, and Taber MacCallum (Class of 1988), who spent a year living in the 'Biosphere', a highly-publicised simulation of the Earth's ecosystem. A total of 34 alumni are also currently with ESA.
The next session will be held this summer, from 1 July to 6 September, in Vienna, Austria.
Master of Space Studies programme
The
Master of Space Studies programme is an 11-month, post-graduate
course aimed at participants ranging from young graduates to
experienced professionals wishing to further their space-oriented
education. It provides a new inter-disciplinary, international
and intercultural educational experience. The programme was
launched last September and the first class (approximately 35
students) is expected to graduate this summer. The course is held
at ISU's permanent campus in Strasbourg.
Continuing professional development
programme
The ISU has also just recently launched
a continuing education programme for professionals. It consists
of short courses (typically one to five days), workshops and
forums to help those interested in keeping up-to-date on new
areas in the space field, or those joining the space field from
another area. Sessions will be held at different locations around
the world.
Further information on ISU can be found on the World Wide Web at:
The Summer School Alpbach is again offering young European scientists and engineers the opportunity to delve further into space-related studies under the guidance of experts in the field. This year, the course will focus on the theme 'Mission to the Moon: Science of the Moon, Science from the Moon'.
The lunar programme requires a long-term vision, but could be a catalyst for Europe's further development in a number of high- technology fields. Through lectures given by highly experienced scientists and engineers, and workshops, participants will examine the Moon's potential as a scientific outpost and as a natural 'space station'.
The Summer School is jointly organised by the Austrian Federal Ministry of Science, Research and the Arts, and the Austrian Space Agency (ASA), and is co-sponsored by ESA. This year's course is also being funded by the European Space Science Committee of the European Science Foundation. As usual, it will be held in Alpbach, a small village in the Austrian Alps, 60 km from Innsbruck, and 150 km from Munich.
The annual courses are open to graduate students and to young scientists and engineers from ESA Member States. For additional information, contact:
Prof. J. Ortner
Austrian Space Agency
Garnisongrasse 7
A-1090 Vienna
Austria
Tel: (43)1.403817712 Fax:
(43)1.4058228
Two spacecraft recently caught the world's attention, but not in the usual way. The Russian Kosmos 398 and the Chinese FSW1-5 (or China 40) re-entered the atmosphere, and it was not known whether fragments, or indeed the whole spacecraft in the case of FSW 1-5, would reach the Earth's surface. Such uncontrolled re- entries pose a potential risk to the population in the area covered by the object's orbit.
ESOC's Mission Analysis Section monitored both re-entries, as it does routinely for space debris. Using basic orbit information obtained by US and Russian space surveillance systems and data modelling, the group is able to predict the time and location of re-entry. ESOC then informs ESA's Member States of the status of the hazard.
Kosmos 398 was launched in February 1971 as part of the Soviet manned lunar programme. Of the satellite's initial mass of about 7 tons, approximately 2.5 tons were still in orbit when the spacecraft re-entered over the South Atlantic in December. Based on infrared observations made from space, it appears that the fragments of Kosmos 398 fell into the Atlantic Ocean.
The Chinese spacecraft FSW1-5 (Fanhui Shi Weixing) was launched in October 1993 into an orbit with an altitude of 250 km. Instead of returning to Earth after 10 days, the re-entry capsule was erroneously inserted into a higher orbit. It re- entered on 12 March, also over the South Atlantic, falling in a tumbling motion which rendered its protective heat shield ineffective. Consequently, only a few fragments of the spacecraft reached the ocean surface.
ESA Bulletin Nr. 86.