in brief - european space agencyglobal timing system (gts) and a radiobiology experiment (called...

r bulletin 102 — may 2000

In Brief

3rd Space StationElement to be LaunchedNASA and the Russian Aviation andSpace Agency (Rosaviakosmos) plan thatthe next component of the InternationalSpace Station (ISS) – the Zvezda servicemodule – will be launched on 12 July fromthe Baikonur Cosmodrome in Kazakhstan.

Following a Joint Programme Review anda General Designers’ Review in Moscow, itwas agreed that Zvezda (Russian for‘star’) will be launched by a Proton rocketwith the second and third stage enginesmodified to increase engine reliability.

Zvezda will provide the early living quartersfor ISS crew, together with the life sup-port, electrical power distribution, datamanagement, flight control, and propul-sion systems for the ISS.

ESA, together with a European industrialconsortium headed by DaimlerChrysler (D)and including Belgian, Dutch and Frenchpartners, was responsible for the design,development and delivery of the core datamanagement system, which providesZvezda’s main computer.

ESA also has a contract withRosaviakosmos and RSC-Energia forperforming system and interfaceintegration tasks required for docking withZvezda by ESA’s Automated TransferVehicle (ATV), which will be used for ISSre-boost and logistics support missionsfrom 2003 onwards. Through its ATVindustrial consortium led by AerospatialeMatra Lanceurs (F), ESA is also procuringsome Russian hardware and software foruse with the ATV.

On the scientific side, ESA has concludedcontracts with Rosaviakosmos and RSC-Energia for the conduct of scientificexperiments on Zvezda, including theGlobal Timing System (GTS) and aradiobiology experiment (called Matroshka)to monitor and analyse radiation doses inISS crew. Cooperation on further scientificexperiments to be conducted on theRussian segment of the ISS is continuingwith Rosaviakosmos and Russia’s IBMP(Institute for Biomedical Research). r

Zvezda (left-most module) is the third

infrastructure element of the International Space

Station (ESA/D. Ducros)

Zvezda integration at the Baikonur

Cosmodrome

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Synergies andCooperation Saveon EuropeanContribution to the ISS

At a ceremony held on 14 April at AleniaSpazio in Turin, Italy, the Columbus flightstructure was handed over to ESA by ASI(Italian Space Agency). On the sameoccasion, the Environmental Control andLife Support Subsystem (ECLSS)ownership transfer from ESA to ASI wasformalised.

Columbus, the cornerstone of ESA'scontribution to the International SpaceStation, is a scientific laboratory scheduledfor launch in 2004. Astronauts fromEurope and elsewhere will be able to usethe laboratory to conduct materialsciences, medicine, biology andtechnology experiments, many eventuallyleading to benefits in commercialprocesses or everyday life on Earth.

The ECLSS, composed of fans, heatexchangers, sensors and motorised andpneumatic valves, all operated andmonitored via the onboard computer,provides comfortable working conditionsinside the space laboratories. In particular,the system controls temperature, humidityand ventilation, regulates atmosphericpressure, detects fire and monitorscontamination of the living environment.

Prior to the ESA Council meeting atministerial level in Toulouse in November1995, it had seemed that approval ofEuropean participation in the ISS would beimpossible to obtain, owing to the excessiveprice of the proposed programme. In mid-1994, ESA had embarked on a serious'design-to-cost' exercise to revive the

programme. The main thrust of this effortwas to make Columbus a four-rack module,similar in length to the ASI Multi-PurposeLogistics Module (MPLM), in order toradically reduce the programme’s designand operational costs.

In the second half of 1994, and into 1995,ESA and ASI reached an agreementwhereby they would cooperate bothgenerally on the development ofpressurised modules and specifically ontwo particular cases. The essence of thisagreement was that:

– ESA would design and verify an Environmental Control and Life SupportSubsystem which would satisfy the requirements of both the MPLM and the Columbus laboratory, and would deliver to ASI engineering models, threesets of flight hardware, some spares and the ground support equipment for the MPLM. ESA would then use this equipment for its Columbus module.

– ASI, which was already developing the MPLM, would supply ESA with a flight unit primary structure for Columbus based on that of the MPLM, and wouldprovide the MPLM qualification data to enable ESA to qualify Columbus on thebasis of commonality, thereby avoiding the need for a separate qualification test model.

Thanks to this agreement, both Agencieswould avoid duplicating high developmentcosts and would help save roughly € 70 million of taxpayers’ money. Furtherreductions arising from the downsizing ofthe Columbus laboratory enabled theColumbus part of the ESA ISSdevelopment programme to be literallyhalved in price, down to approximately

€ 700 million. On that basis, the ministersresponsible for space gathered inToulouse in November 1995 were able toapprove the overall ISS programme.

Alenia Spazio, as the MPLM primecontractor, manufactured the structureand performed ECLSS integration for theMulti-Purpose Logistics Module under ASIcontract; DASA-Dornier, as the ECLSSsubcontractor for Columbus, wasentrusted with ECLSS development andverification under a contract with ESA. Theindustrial activities were jointly controlledby ESA and ASI.

In addition to these specific jointdevelopments, further synergies werefound. Alenia Spazio became the primecontractor for ISS Nodes-2 and -3, acontract managed by ASI on behalf ofESA, the price of which is being used tooffset the launch costs of the Columbuslaboratory by NASA's Space Shuttle.European industry is thus developinghardware for the Station using ESA funds,rather than ESA paying NASA in dollars forthe launch of Columbus.

Alenia Spazio is also the contractor for thepressurised Carrier part of the AutomatedTransfer Vehicle (ATV) which, launchedatop Ariane-5, will be used as a 'ferry'vehicle for payload, propellant, fresh foodand general provisions.

This agreement has also fostered anincreasing use of common subcontractors(and hence common design principles) forthe Columbus and Node harnesses andMechanical Ground Support Equipment(OHB, Germany) and Thermal ControlSubsystems (Microtecnica, Italy), furtherimproving the cost-efficiency of Europeanhuman spaceflight projects. Thesesynergies will continue into the operationalphase, in terms of integration, payloadoperation and logistics activities.

The final ECLSS equipment and theColumbus primary structure were deliveredin March/April. Much of the ECLSShardware is already at NASA/KennedySpace Center awaiting the first launch ofthe MPLM Leonardo, currently planned forFebruary 2001, but several tonnes ofECLSS and structure equipment can stillbe viewed in Turin, together with otherelements of ASI and Alenia Spazio'scontribution to the development of theInternational Space Station. r

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Physics on Stage

Physics is everywhere. The laws ofphysics govern the Universe, the Sun, theEarth and even our own lives. In today’srapidly developing society, we arebecoming increasingly dependent on hightechnology – computers, transport andcommunication are just some of the keyareas that are the result of discoveries byscientists working in physics.

But how much does the average personreally know about physics? There is now aunique opportunity to learn more aboutthis elusive subject! Three major Europeanresearch establishments have organised aunique Europe-wide programme to raisepublic awareness of physics and relatedsciences.

'Physics on Stage' was launched inFebruary by ESA, CERN (EuropeanLaboratory for Particle Physics) and ESO(European Southern Observatory) withsupport from the European Union. Otherpartners include the European PhysicalSociety (EPS) and the EuropeanAssociation for Astronomy Education(EAAE). This exciting programme is part ofthe European Week for Science andTechnology and will culminate in a ScienceFestival, on 6-11 November, at CERN(Geneva).

The primary goal of 'Physics on Stage isto heighten interest in and knowledge ofphysics in Europe by means of a series ofhigh-profile, physics-related activities. Itwill bring together leading scientists andeducators, government bodies and themedia, to confront the diminishingattraction and knowledge of physics inyoung people and to develop strategies toreverse this trend. The objective in theshort term is to infuse excitement and toprovide new educational materials. In thelonger term, it will generate new develop-ments by enabling experts throughoutEurope to meet, exchange and innovate.

During the first phase of the programme(until October), the National SteeringCommittees (NSC) will survey their owncountry's* respective situation andcollaborate with national media to identifynew and exciting educational approachesto physics. These may involve demon-strations, interactive experiments, videoand CD-Rom presentations, webapplications, virtual reality, theatreperformances, etc. Nationally-run

competitions will select some of the bestand most convincing new ideas forpresentations and educational materialswhich will receive development supportfrom the programme.

The project will culminate in November2000, with approximately 400 delegatesconverging at CERN for the 'Physics onStage' conference. The conference willenable the national competition winners,science teachers, science communicators,publishers, top scientists and high-levelrepresentatives of the ministries andEuropean organisations to brainstormsolutions to bolster the popularity ofphysics. The conference will also includespectacular demonstrations of educationaltools, the best of which will be disse-minated over national TV networks andother media to the European public.

Statements by the Directors Generalof ESA, CERN, and ESO

Antonio Rodotà (ESA): "Space hasbecome an integral part of every day life.The immense technological developmentthat has led to this achievement has takenplace and might be taken for granted. Butnow is the time to follow up and form thefuture on this basis, a future that has to bemade by the youth and has to give itsbenefits to the youth. The EuropeanSpace Agency is dedicated to support theyouth in its development to become aspace generation. Many activities havebeen done and are taking place, andmany more are planned for the future.Teachers and educational institutions andorganisations form a key role in thisdevelopment. ESA is enthusiastic aboutcooperating with ESO, CERN and theEuropean Union to create an opportunityto receive ideas from the educationalsociety and will perform a dedicated effortin finding ways to support the realisationof those ideas."

Luciano Maiani (CERN): "Science is acritical resource for mankind and, amongnatural sciences, physics will continue toplay a crucial role, well into the nextcentury. The young people of Europedeserve the best possible physicsteaching. An enormous resource of firstclass teachers, teaching materials andinnovative thinking exists in our countries.The 'Physics on Stage' project will bringthese together to generate a new interestin physics education which will be to thelong-term benefit of children all over

Europe. CERN is delighted to take part inthis collaboration between the EuropeanCommunity and the continent's threeleading physics research organisations."

Catherine Cesarsky (ESO): "Astronomyand astrophysics are at the very heart ofmodern physics. As vibrant researchdisciplines they use the most advancedtechnology available to humanity toexplore the cosmos. It is also a science ofextreme conditions – the largestdistances, the longest periods of time, thehighest temperatures, the strongestelectrical and magnetic fields, the highestand lowest densities and the mostextreme energies. The cosmos is indeedthe greatest physics laboratory. For years,ESO - Europe's Astronomy Organisation -has been engaged in communicating theoutcome of the exciting researchprogrammes carried out at the ESOobservatories to a wide audience and inparticular to Europe's youth. I warmlywelcome the broad internationalcollaboration within 'Physics on Stage'. Iam confident that working together withthe European Union and our sisterorganisations ESA and CERN, as well asteachers' organisations and dedicatedindividuals in all member countries, thisinnovative education programme will makea most important contribution towardsraising the interest in fundamentalresearch in Europe."

* 'Physics on Stage' is being initiated in 22 Europeancountries which are members of at least one of theparticipating organisations or the EU: Austria, Belgium,Bulgaria, the Czech Republic, Denmark, Finland,France, Germany, Greece, Hungary, Ireland, Italy,Luxembourg, the Netherlands, Norway, Poland,Portugal, the Slovak Republic, Spain, Sweden,Switzerland, United Kingdom. More information can befound via the 'Physics on Stage' website:<http://www.estec.esa.nl/outreach/pos>. r

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ESA 2000 SpaceScience Exhibition

The ESA 2000 Space Science Exhibition(13 March - 25 May) was opened by Prof.R. Lüst (ESA's Director General from 1984to 1990) during the inauguration of thenew Schwarzschild-building of theAstrophysical Institute Potsdam inGermany. A scientific talk was also givenby Prof. R. Giacconi (AssociatedUniversities Inc., Washington).

ERS-1:Nine-yearSuccessStoryComes toan EndHaving givenexcellent servicefor nine years,

over three times its planned lifetime, theERS-1 mission was ended on Friday 10 March by a failure in the onboardattitude control system. Since its launchon 17 July 1991, ESA’s first sun-synchronous polar-orbiting mission, hasmade 45 000 orbits, acquiring more than1.5 million individual Synthetic ApertureRadar (SAR) scenes. ERS-1 SAR images,

together with the data from otherinstruments on board, were delivered to aworldwide community of some 4000 usersin science and applications. Surface windsderived from the scatterometer andaltimeter have been supplied tometeorological services worldwide since1991. The duration of the mission has alsomeant that scientists have alreadyobserved several El Niño phenomenathrough combined obser-vations ofsurface currents, topography, temperaturesand winds. The measurements of seasurface temp-eratures, critical to theunderstanding of climate change, madeby the ERS-1 Along-Track ScanningRadiometer, are the most accurate everfrom space. All these criticalmeasurements are being continued andenhanced by the current ERS-2 mission.

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The exhibition consisted of 8 scale modelsand more than 70 information panelswhich informed the public about ESA ingeneral and its science missions inparticular. In addition, guided tours,videos, and the ESA brochures ‘ESA 2000

The scientific programme of the EuropeanSpace Agency’ and ‘Success Story: 30discoveries from ESA's science missionsin space’ provided further insight. r

The most exciting results from the ERS-1mission have been in the field of SARinterferometry, where for the first timeprecise topographic information could beroutinely produced from space data. TheERS-1 and ERS-2 tandem operationsdemonstrated this technique for variousapplications and paved the way for thedefinition of new dedicated SARinterferometry missions. ERS-2 (launchedin 1995) took over the operational servicesof ERS-1 in 1996. It too has nowexceeded its nominal lifetime and remainsin excellent condition. Next year Envisatwill be launched to continue this series ofEarth Observation missions. r

The XMM-Newton modelwelcomes visitors in theexhibition entrance hall(photo courtesy E. Popow)

At the exhibition (left toright): Dr G. Hartmann(DLR, Bonn), Prof G.Hasinger (Director AIP),Prof R. Lüst (MPI forMeteorology) and Dr F.Jansen (author of ESA2000).(photo courtesy E. Popow)


Long-Term OzoneMeasurements fromSpace Assured

The continued monitoring of ozone isassured well towards the end of the nextdecade through a € 38.3 million contractsigned on 3 March in Florence, Italy forthree new Global Ozone MonitoringExperiment (GOME-2) instruments.

GOME-2 is an enhancement of the ESAGOME-1 instrument flown on ERS-2, theEarth Observation satellite which,continues to provide a wealth of scientificdata from orbit. Within the EUMETSATPolar System, consisting of a spacesegment comprised of three METOPsatellites and their payloads, and a groundsegment for command, control and dataprocessing, GOME-2 is the operationalinstrument specifically devoted tomeasuring the ozone content in theatmosphere. GOME-2 measurements willallow the daily global retrieval of totalozone and vertical ozone profile in theatmosphere and, in addition, themeasurement of atmospheric trace gases.

The EUMETSAT Polar System and theESA METOP-1 Programme together forma cooperative venture between the twoorganisations, and lead to the launch ofthe first METOP satellite in mid-2003. Thesystem provides operational meteoro-logical data from polar-orbiting satellites,

to complement and complete aninternational system of polar satellitesoperated together with the US.

The variations of atmospheric ozone are ofvital importance for many reasons, and itsdistribution in the atmosphere needs to bemapped continuously. The enhancedGOME-2 instrument on METOP willcontinue the series of ESA measurementsstarted by GOME-1 on ERS-2 and to beprovided by the SCIAMACHY instrumenton ESA’s environmental satellite Envisatdue to be launched in 2001.

In addition, to innovative data forNumerical Weather Prediction, one of themost important contributions of GOME-2will be the continuation and improvementof the climate record of ozone. Monthlyand seasonal maps of ozone distributionthroughout the atmosphere will provide arecord of its variation with time and willhelp detect long-term trends of majorimportance for the health of the planetand its population. r

ISU Summer Session

The International Space University is anon-profit organisation, founded in 1987,with the aim of educating professionals inthe field of space and its peacefulapplications. Its programs are designed tomeet the needs of a rapidly expandingsector where international and cross-disciplinary understanding and cooperationare fundamental to the success of futuredevelopment. Specialised educationalopportunities and training are offered byinternational experts in all space-relateddisciplines from a global perspective.Programmes include: Master of SpaceStudies, Professional DevelopmentPrograms, tailor-made Forum Activitiesand the ISU Summer Session.

ISU Summer Session Program (SSP)This intensive summer program covers the

principal space-related fields, bothtechnical and non-technical. These includespace and society, space business andmanagement, space policy and law, spacesystem architecture and mission design,space engineering, space resources,robotics and manufacturing, satelliteapplications, space physical sciences,space life sciences and an informaticslecture series.

The interdisciplinary curriculum with itsemphasis on international cooperationgives students broad new perspectives onthe world's space activities, perspectivesotherwise reserved for those with years ofprofessional experience.

The SSP has proved to be an excellentforum where students and faculty alikecan network with leaders in spaceresearch and development from around

the globe. The interactive, internationalenvironment provides participants withnumerous opportunities to forge newprofessional relationships. SSP alumni,numbering over 1200 to date, facultymembers, visiting lecturers and membersof the host community have all contributedto creating a professional networkfacilitating access to information andexchanges.

Summer Session 2000This year's summer session will take placefrom 1 July - 2 September and is hostedby the Universidad Tecnica Federico SantaMaria in Valparaiso, Chile.

For more information visit the ISU SSP siteat: <http://www.isunet.edu/Programs/SSP/SSP.html>. r

The contract on the procurement of three flight models of the GOME-2 instrument was signed by(left to right) Dr. Giancarlo Grasso, Deputy Head, Defence Sector of Finmeccanica for AleniaDifesa/Officine Galileo BU Spazio, Dr. Claudio Mastracci, ESA Director of Applications Programmes,and Dr. Tillmann Mohr, EUMETSAT Director

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SOHO Top Comet Finder

Calculations confirm that a comet spottedby a Lithuanian astronomer on 4 Februaryis a previously unknown object, making itthe 100

thcomet discovered with the

SOHO spacecraft.

Launched four years ago as a project ofinternational cooperation between ESAand NASA, the Solar and HeliosphericObservatory has revolutionised thescience of the Sun.

Although this latest comet, SOHO-100, isan 'ordinary' comet, SOHO has alsorevealed an amazing number of kamikazecomets plunging into the solar atmos-phere, which help to make SOHO themost prolific comet finder in the history ofastronomy.

Like nearly all of SOHO's discoveries, the100th comet showed up in images fromthe LASCO instrument. This is a set ofcoronagraphs that view the space aroundthe Sun out to 20 million kilometres, whileblotting out the bright solar disk withmasks. Developed for SOHO by amultinational team led by the US NavalResearch Laboratory, LASCO watches formass ejections from the Sun that threatento disturb the Earth's space environment.The comet discoveries are a big bonus.

SOHO's experts spot many of the cometsas soon as the images come in. But stillpictures and movies from LASCO arefreely available on the Internet toastronomers around the world, who candiscover less obvious comets withoutleaving their desks. This was the casewhen Kazimieras Cernis of the Institute ofTheoretical Physics and Astronomy inVilnius, Lithuania, found SOHO-100.

"On 4 February I saw the comet as asmall speck of light in the previous day'sLASCO images," Cernis explained. "It hadno visible tail, but it was too fuzzy to be anasteroid. By the time I had seen the objectmoving steadily across the sky in sixsuccessive images, I was convinced itwas a comet and I sent the details to theSOHO scientists for verification."

The competition to find SOHO's 100th

comet was keen. An amateur astronomer,Maik Meyer of Frauenstein, Germany,discovered SOHO-98 and -99. On 5February, less than 24 hours after Cernisreported the candidate SOHO-100, Meyer

found the candidate SOHO-101. On thesame day and in the same LASCOimages, Douglas Biesecker, a member ofthe SOHO science team, spotted thecandidate SOHO-102 travelling ahead of101. Computations have now validatedthe orbits for all three candidates, andshown them to be bona fide cometdiscoveries.

Other amateur astronomers have used theLASCO images to find comets. In thesummer of 1999, Terry Lovejoy in Australiafound five and, since September 1999, anamateur in England, Jonathan Shanklin,has spotted three more.

"SOHO is a special chance for comethunters," said Shanklin, Director of theBritish Astronomical Association's cometsection. "It allows amateurs to discoversome of the smallest comets ever seen.Yet they link us to sightings of greatcomets going back more than 2000years."

Nine of the comets found with LASCO,including SOHO-100, 101 and 102,passed the Sun at a safe distance.SOHO-49, which showed up in LASCOimages in May 1998 and was designatedas Comet 1998 J1, became visible to thenaked eye in the Southern Hemisphere.But the great majority of SOHO's cometsfailed to survive very close encounterswith the Sun.

Snowballs in hellOf the first 100 SOHO comets, 92vaporised in the solar atmosphere. IsaacNewton suggested 300 years ago thatinfalling comets might supply the Sun withfuel, but no one has ever tracked a cometthat definitely hit the bright surface. Nearmisses are well known, and 100 years agoHeinrich Kreutz in Kiel, Germany, realisedthat several comets seen buzzing the Sunseemed to have a common origin,because they came from the samedirection among the stars.

These comets are now called the Kreutzsungrazers, and the 92 vanishing SOHO

comets belong to that class. They werenot unexpected. Between 1979 and 1989the P78-1 and SMM solar satellitesspotted 16 comets closing with the Sun.

Life is perilous for a sungrazer. Themixture of ice and dust that makes up acomet's nucleus is heated like the proverbialsnowball in hell, and can survive its visit tothe Sun only if it is quite large. What'smore, the very strong tidal effect of theSun's gravity can tear the loosely gluednucleus apart. The disruption that createdthe many SOHO sungrazers was similar tothe fate of Comet Shoemaker-Levy 9,which went too close to Jupiter and brokeup into many pieces that eventually fellinto the massive planet in 1994. r

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In this coronagraph image, the shaded red disk is a mask in the LASCO instrument that bolts outdirect sunlight. The white circle added within the disk shows the size and position of the visible Sun.the square black outline (upper left) shows the position of SOHO-100 and the larger black outline isa zoomed-in view


"SOHO is seeing fragments from thegradual breakup of a great comet,perhaps the one that the Greekastronomer Ephorus saw in 372 BC,"commented Brian Marsden of the Centerfor Astrophysics in Cambridge,Massachusetts. "Ephorus reported thatthe comet split in two. This fits with mycalculation that two comets on similarorbits revisited the Sun around AD 1100.They split again and again, producing thesungrazer family, all still coming from thesame direction."

The sungrazing comets slant in from thesouth, at 35° to the plane where the Earth and the other planets orbit. AsSOHO moves around the Sun, in stepwith the Earth, it sees the cometsapproaching the Sun from the east (left) in February and from the west (right) inAugust. In June and November thesungrazers seem to head straight uptowards the Sun.

"The rate at which we've discoveredcomets with LASCO is beyond anythingwe ever expected," said DouglasBiesecker, the SOHO scientist personallyresponsible for the greatest number ofdiscoveries, 45. "We've increased thenumber of known sungrazing comets by afactor of four. This implies that there couldbe as many as 20 000 fragments."

Their ancestor must have been enormousby cometary standards. Although SOHO'ssungrazers are all too small to survive,other members of the family are still largeenough to reappear, depleted but intact,after their close encounters with the Sun.Among them were the Great SeptemberComet (1882) and Comet Ikeya-Seki(1965).

The history of splitting gives clues to thestrength of comets, which will be ofpractical importance if ever a cometseems likely to hit the Earth. And thefragments seen as SOHO comets revealthe internal composition of comets, freshlyexposed, in contrast to the much-alteredsurfaces of objects like Halley's Cometthat have visited the Sun many times.LASCO reveals how much visible dusteach comet releases. Gas produced byevaporating ice is detected by anotherinstrument on SOHO, the UltravioletCoronagraph Spectrometer or UVCS, andenables scientists to measure the speedof the solar wind as it emerges from theSun.

A comet spotted by its gas cloudThe count of SOHO's comet discoverieswould be one fewer without a recentbonus from SWAN. This instrument'sname unpacks into Solar WindAnisotropies, and it was provided by theFrench Service d'Aéronomie and theFinnish Meteorological Institute. SWANlooks away from the Sun to survey atomichydrogen in the Solar System, whichglows with ultraviolet light and is altered bythe solar wind. The instrument also seeslarge clouds of hydrogen surroundingcomets, produced by the breakup ofwater molecules evaporating from thecomets' ice.

In December 1999, the InternationalAstronomical Union retrospectivelycredited SWAN and SOHO with findingComet 1997 K2 in SWAN full-sky imagesfrom May to July 1997. It made number93 on the SOHO scorecard. This cometremained outside the orbit of the Eartheven at its closest approach to the Sun.Although it was presumably a small, faintcomet, the gas cloud grew to a width ofmore than 4 million kilometres.

"The discovery was a surprise," saidTeemu Mäkinen, a Finnish member of theSWAN group. "Our normal procedure is toobserve hydrogen clouds of cometsdetected by other people. In that respect,SWAN on SOHO is the most importantinstrument now available for routinelymeasuring the release of water vapourfrom comets."

When Comet Wirtanen, the target forESA's Rosetta mission (2003), made itsmost recent periodic visit to the Sun, itpumped out water vapour at a rate of 20 000 tons a day, according to theSWAN data. For the great Comet Hale-Bopp the rate reached 20 million tons aday and SWAN watched its hydrogencloud grow to 70 million kilometres – byfar the largest object ever seen in theSolar System.

For further information on SOHO, picturesand movies visit the ESA science webpages at<http://sci.esa.int/soho > and<http://sohowww.estec.esa.nl>. r

Farewell to a LegendaryMission

ESA hands the IUE archive over to theglobal scientific community

The IUE (ESA/NASA/UK) spacecraftlaunched in January 1978 became the firstspace observatory facility available to theentire astronomical community. It markedthe beginning of UV astronomy, a field forwhich space telescopes are essentialsince UV light does not reach the Earth'ssurface. By the time IUE was switched off,in September 1996 – 14 years later thanoriginally planned – IUE had changed theview astronomers had of the Universe.Among many other findings, IUEdiscovered the auroras in Jupiter;detected for the first time the halo in ourgalaxy and measured the size of a blackhole in the core of an active galaxy.

The IUE archive, storing two decades ofultraviolet astronomy, has become ahistorical reference. It contains more than110 000 spectra from observations that inmost cases cannot be repeated, and is anexcellent source for studying variablephenomena. The long time-lapse coveredand the stability of the instrument haveenabled astronomers to witness eventsthey never thought they would. Thearchive was the first of its kind accessibleonline – already in 1985, when the WorldWide Web did not yet exist – and hasbeen a key catalyst for science. To date, ithas triggered the publication of some3600 articles in refereed journals and awhole generation of astrophysicists hasused IUE data at some stage.

Now, the IUE archive will belong to theglobal scientific community. ESA has justreleased the new IUE archive, INES (IUENewly Extracted Spectra) as the firstastronomical database distributed tonational data centres all over the world forfaster and easier access. "This is the bestfarewell from ESA to a historic mission.Thanks to the new distributed system theIUE archive will become both a mine ofdiscoveries and a powerful educational aidfor future astronomers. It is a legacyworthy of the IUE project", says WillemWamsteker, ESA astronomer and ESA IUEProject Scientist.

"The INES system and its data guaranteethat future generations of astronomers willbe able to use IUE data as much as theywant, regardless of whether they know

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about the technicalities of the mission orwhether there is an improvement inarchive technology. And the distributedstructure is better adapted to changes inuser needs than a single archive centre",says Antonio Talavera from the Laboratoryfor Space Astrophysics and TheoreticalPhysics (LAEFF), based at Villafranca."ESA has created INES using a minimalistengineering approach for the worldscientific community, and has made it tolast. INES is easy to use and easy toupgrade, and LAEFF in Spain is proud toserve as the hub for the whole world".

The INES Principal Centre is at the LAEFF,owned by INTA, the Spanish NationalInstitute for Aerospace Technology. Thiscentre, with a data mirror at the CADC inVictoria (Canada), holds the completedatabase and provides information notavailable from national hosts. So far 17national hosts have come online. Togetherthey form with the Principal Centre anefficient and highly reliable distributionsystem for the community. The wholeprocess of data retrieval is fully automatedand totally transparent to the end user.This distributed structure avoids localisedconnectivity problems and guaranteesavailability of data. r

tons. Even the engineers who haveworked on it for years are still impressedby the size of the satellite.

Designed for at least 5 years of in orbitoperation, Envisat with its ten highlyadvanced instruments on board will helpEuropean scientists advance ourunderstanding of global warming, climatechange, ozone depletion, and changes inthe oceans, ice sheets, vegetation andatmospheric composition. Thanks inparticular to its advanced imaging radar,Envisat will produce – all weather day andnight – high-quality images of the oceans,coastal zones, polar ice and land regions.

The solar array will be integrated earlysummer. After a solar array deploymenttest, Envisat will be submitted to acoustictests in the Large European AcousticFacility (LEAF). The HYDRA hydraulicshaker will then be used to check thesatellite’s ability to cope with the vibrationsit will experience during the launch phase.With its eight actuators delivering a forceof 60 000 newtons each, the HYDRA isone of the largest test facilities of its kind.

With the Envisat flight model testprogramme, ESTEC demonstrates itscapabilities as one of the most completetest centres in the world. Over 100 highlyskilled specialists from ESA and Europeancompanies, led by the prime contractorsMatra-Marconi Space (UK) for the satelliteplatform and DaimlerChrysler-DornierSatellitensysteme (D) for the payload, arecurrently involved in the testing of Envisat.In March next year the spacecraft will

Envisat, the LargestEnvironmental SatelliteTakes Shape at ESA'sTest CentreESA's Envisat satellite is currentlyundergoing integration and tests at theEuropean Space research and TechnologyCentre (ESTEC) in the Netherlands.

Last August, the Envisat Payload andService Modules were submitted tothermal and space environment tests inESTEC's Large Space Simulator (LSS).

While the flight model instruments wereprogressively integrated on board thePayload Module, the Service Moduleverification was proceeding in parallel,including the recent demonstration ofcompatibility to the Ariane-5 in-flightshocks and separation tests.

Mating of these two modules of Europe’slargest-ever environmental satellite tookplace at ESTEC’s test facilities in mid April.Envisat stands over 10 metres tall and thetwo elements combined weigh over 8

finally be prepared for shipment toKourou.

Scheduled for launch on an Ariane-5 inJune 2001, Envisat will fly on a Sun-synchronous orbit at about 800 kmaltitude with an orbit repeat cycle of 35days, identical to the ERS-2 ground track.ESA's European Space Operations Centre(ESOC) in Darmstadt, Germany, will handlethe command and control of Envisat. TheAgency's Earth Oservation applicationteam, located at ESRIN, Frascati, Italy, willcoordinate the payload data exploitationfrom instrument data recovery to deliveryof products to the scientific andapplication user communities.

Once in orbit, Envisat will provide remotesensing data of unprecedented quality,helping Europe to meet the environmentalchallenges of the 21st Century. r

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The INES Newsletter and Brochure are available from ESA Publications <http://esapub.esa.int>


ESA’s First BiomedicalApplication ResearchContract for the ISS

ESA and researchers from academia andindustry signed the contract on 3 May fora health research project that will developa space bioreactor for research aboardthe International Space Station intobiomedical applications. At the ceremony,held in the Erasmus User Centre atESTEC, Mr Jörg Feustel-Büechl, ESA'sDirector of Manned Spaceflight andMicrogravity, pointed out that "This is thefirst in a series of almost 50 contracts forapplication-oriented research projects thatinvolve the International Space Station."

A bioreactor is used for growing bacteria,yeast or animal cells and, more recently,for tissue. The new bioreactor will bedesigned specifically for cultivating medically-relevant mammalian cells, tissues andorgan-like structures, with particularemphasis on vessels and cartilage.

Millions of people every year suffer organand tissue loss from diseases andaccidents. Transplantimg tissues andorgans from other human bodies isseverely limited by the availability of donors.Taking tissue samples from healthy areasof the patient's own body, growing themin vitro, outside the patient's body, to asize and structure which then allow theirreimplantation into the damaged parts is apromising alternative. Reimplantation alsoavoids the fundamental problem ofrejection of foreign tissues and organs.Growing tissue samples in vitro – in abioreactor – is currently one of the majorgoals of medical research. It is expectedthat such techniques will revolutionisebiomedical and surgical procedures in thenear future. Space research may beinstrumental for the breakthrough in tissueengineering – the microgravityenvironment may provide much betterconditions for obtaining proper 3D cellstructures.

A potential application is the masscultivation on Earth of biological implantsto regenerate the meniscus and articularcartilage of the knee, using techniquesresulting from the space experiments.Cartilage regeneration is urgently neededfor 20 to 50 year-old patients, many ofthem suffering from sports accidents. Thedemand for such implants in Europe aloneis estimated to be 100 000 per year.

The modular space bioreactor formedically-relevant organ-like structureswas proposed by a European scientificand industrial research team under thecoordination of Prof. Augusto Cogoli fromthe Swiss Federal Polytechnical University(ETH) Zurich. It will be essential inclarifying the cellular and molecularmechanisms responsible for cellaggregation and differentiation controlmechanisms, and in obtaining betterpseudo-organs for possible clinical uses.

Prof. Cogoli's team comprises participantsfrom Switzerland, Italy and Germany: Dr.Isabelle Walther from ETH, Dr. WernerMüller from the Sulzer Medica company inWinterthur (CH), Prof. Saverio Ambesi-Impiombato from the University of Udine(I), Dr. Augustinus Bader from the MedicalUniversity of Hannover (D), Prof. PeterBruckner from the University of Münster(D) and Dr. Ralf Pörtner from the TechnicalUniversity of Hamburg-Harburg (D).

The modular space bioreactor project isone of more than 50 microgravityapplication projects for the Space Stationthat ESA expects to initiate in the nearfuture. They will use the Station to obtainapplication-oriented data that providedeeper insights into Earth-based industrialprocesses or be used in numericalsimulations. The availability of the SpaceStation means that examining specificapplied-research questions in that uniqueenvironment may be, in the long term,rewarding for industry.

The modular space bioreactor project issponsored by ESA's MicrogravityApplications Promotion Programme and isfunded jointly with the participating

scientific research institutes and industry.A major aspect of this MAP Programme isthe setting up of Europe-wide teams andnetworks involving partners fromacademia and industry to work togetheron industrially-relevant research. The aimis to initiate concrete industrial projects inwhich terrestrial research with industrialobjectives and commercial funding,together with the participation ofresearchers from scientific institutes, aresupported by ESA, including thesponsoring of space flight opportunitiesand associated ground-based activities.

Prof. Cogoli and his scientific-industrialteam proposed the space bioreactorproject in response to ESA's firstAnnouncement of Opportunity (AO) forPhysical Sciences and Biotechnology. This 1998 AO for Space Station researchproposals produced 145 responses,substantially exceeding expectations. Aftera review by independent peers, 6 proposalswere rated as ‘outstanding’, 26 as ‘highlyrecommended’ and 30 as ‘recommended’.Of these, 31 dealt with application-orientedresearch, including thermophysicalproperties of liquid metals, advancedfoams, biological tissue culturing,osteoporosis and combustion processes.

The peer review panel summarised itsevaluation of the proposal made by Prof.Cogoli and his team as "The proposal forproducing cartilage … is an outstandingand innovative approach. … this may bethe only way for in vitro production of afunctional cartilage analogue. Thisapproach cannot be done except under microgravity conditions.” r

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Mr Jörg Feustel-Büechl (left) and Prof Augusto Cogoli sign the contract for the first in a series ofalmost 50 new projects in ESA’s Microgravity Applications Promotion Programme

Historic WA Town toHost Deep SpaceGround Station

The start of construction of a Deep SpaceGround Station, just outside the historicmonastic town of New Norcia, WesternAustralia, has been marked with aFoundation Stone Laying Ceremony byESA on Thursday, 2 March 2000.

Mr David Dale, ESA Director of Technicaland Operational Support, and the WesternAustralian Minister for Planning, GrahamKierath, officially buried a time capsule andlaid the first foundation stone.

Part of ESA's global network, the GroundStation features a 35-metre high antennawhich will be built 8 km south of NewNorcia.

The $40 million antenna will transfer datato and from ESA's deep space missions.The first large mission, the Rosettasatellite, will leave in 2003 on a 10-yearmission to study the Wirtanen Comet.Rosetta will send a Lander to the surfaceof the comet to analyse its structure andcomposition.

The antenna will also communicate withESA's first mission to Mars. The MarsExpress will also be launched in 2003 aspart of an international flotilla of spacecraftsent to study the planet.

Construction of the antenna towercommenced in April. Components for theantenna will be shipped from Europe andassembled on site. The expectedcompletion date is Spring 2001.

Mr Dale said New Norcia was chosen overa number of sites in the SouthernHemisphere. "This site has excellentweather conditions, sits on the perfectlatitude for the launch operations and issufficiently distant from urban areas sothat no other transmission devices disturbthe satellite's operations." "WesternAustralia also has high quality telecom-munications infrastructure and we areworking closely with Telstra because of itsexperience in the maintenance andoperation of tracking stations."

Bovis Lend Lease will oversee theconstruction under the leadership of theCanadian company, SED, which will headthe International Antenna Consortium

formed to manage the project. Telstra hasbeen contracted to maintain the GroundStation on ESA's behalf.

Further information is available from ESOCPublic Relations (Robert-Bosch-Str. 5,64293 Darmstadt, Germany). r

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Site of the new Deep Space Ground Stationoutside New Norcia, Western Australia

Mr David Dale (right), ESA Director of Technicaland Operational Support, and Mr GrahamKierath, Western Australian Minister forPlanning, during the stone laying ceremony


ESA Astronaut BringsBack New Views ofEarthGerman astronaut Gerhard Thiele landedback on Earth on 22 February with his fiveinternational colleagues after a ground-breaking Space Shuttle mission that willchange the way we look at the Earth.

The Space Shuttle Endeavour glided to anearly evening landing at the KennedySpace Center, touching down on therunway after a mission of over 11 days.

Elated scientists from all over the worldgave the international SRTM team astanding ovation and heralded the missionas a huge success.

ESA astronaut Gerhard Thiele, completinghis first space flight, described the missionas a 'fantastic experience'. "We havemapped regions that are home to 95% ofthe world's population and this data will

be used to produce unrivalled three-dimensional images of the world," he said.

Orbiting at 233 km above the Earth, withtwo radar antennas mounted in theShuttle payload bay and two extended ona 60-metre mast, the imaging system hasmeasured the undulations of landscapesthat have been sculpted through themillennia.

NASA extended mapping operations fornine hours, allowing Endeavour'sastronauts to continue collecting data untila day before returning to Earth and,therefore, achieving almost 100 percent ofthe planned coverage. The mission'starget mapping area included about 123million square kilometres and more than65% of this – nearly 80 million squarekilometres – was mapped with two ormore passes.

The Shuttle Radar Topography Mission(SRTM), consisting of a specially modified

radar system, was designed to demon-strate the technology for obtaining high-resolution digital topographic maps of theEarth. The radar has imaged mountainsand deep valleys carved by glaciers andrivers – like those in the Andes, the RockyMountains and the Himalayas of Asia –vast expanses of deserts and coastalplains around the world, as well as coldregions and forests of the northernlatitudes.

In the future, any project that requiresaccurate knowledge of the shape andheight of the land – such as flood control,soil conservation, reforestation or volcanomonitoring – will benefit.

After a series of delayed launch attempts,the mission got off to a perfect start on 11February with Thiele reporting successfuldeployment of the 60 metre radar mast –the longest structure to be flown in spacefrom the Shuttle – and activation of thecomplex radar instruments going moresmoothly than expected. "We'd expectedthat there would be more teethingproblems but the intensive training andpreparations paid off," he said.

STRM is a joint project between NASA,the United States National Imagery andMapping Agency (NIMA), the GermanAerospace Centre (DLR) and the ItalianSpace Agency (ASI). NASA's JetPropulsion Laboratory (JPL) developed theC-band Spaceborne Imaging Radar andDLR developed the X-band SyntheticAperture radar (X-SAR). DornierSatellitensysteme GmbH, a corporate unitof Daimler-Chrysler Aerospace (Dasa), isthe prime contractor for the X-SARsystem.

Although the first images have alreadybeen released, the gathering of the radardata from orbit marks only the end of thefirst phase. Scientists will spend another18 months processing the huge volume ofSRTM data.

For further information, see the followingweb pages:ESA:<http:/www.estec.esa.int/spaceflight/operations/sts99.htm>DLR: <http://www.dlr.de/srtm>NASA:<http://spaceflight.nasa.gov/shuttle>

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The STS-99 crew poses at the entrance to the orbiter Endeavour. From left are Mission SpecialistsJanet Lynn Kavandi (NASA), Gerhard Thiele (ESA), Janice Voss (NASA) and Mamoru Mohri(NASDA), Commander Kevin Kregel (standing) and Pilot Dominic Gorie (kneeling)

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This topographic image of Patagonia,Argentina, shows a spectacular landscapeformed by volcanoes, rivers, and wind. Thearea is located just east of the narrow range ofthe Andes Mountains, about 100 km east of theborder with Chile. Interesting features includebasalt-capped mesas with sink holes (lowercentre), arcuate ridges of windblown beachsands downwind from a salty desert lake (uppercentre), young volcanic cones (right). Acomputer-generated artificial light sourceilluminates the elevation data to produce apattern of light and shadows. Colours show theelevation as measured by SRTM, ranging fromblue at the lowest, to white at the highestelevations. White speckles on the face of someof the mountains are holes in the data causedby steep terrain and will be filled using coveragefrom an intersecting pass. Geologists will useSRTM topographic data to study the interactionof volcanic, climatic and erosion processes

California’s Garlock Fault, marking thenorthwestern boundary of the Mojave Desert,lies at the foot of the mountains, running fromthe lower right to the top centre of this image.These mountains are the southern end of theSierra Nevada and the prominent canyonemerging at the lower right is Lone TreeCanyon. In the distance, the San GabrielMountains cut across from the left side of theimage. At their base lies the San Andreas Fault,which meets the Garlock Fault near the leftedge at Tejon Pass. The dark linear featurerunning from lower right to upper left is StateHighway 14 leading from the town of Mojave inthe distance to Inyokern and the Owens Valleyin the north. The lighter parallel lines are dirtroads related to power lines and the LosAngeles Aqueduct which run along the base ofthe mountains. The data will be used bygeologists studying fault dynamics andlandforms resulting from active tectonics

Honolulu, on the island of Oahu, is a large andgrowing urban area with limited space andwater resources. This perspective view,combining a Landsat image with STRMtopography, shows how the topographycontrols the urban growth pattern, causescloud formation, and directs the rainfall runoffpattern. Features of interest in this sceneinclude downtown Honolulu (right), Honoluluharbour (right), Pearl Harbor (centre), andoffshore reef patterns (foreground). The Koolaumountain range runs through the centre of theimage. Clouds commonly hang above ridgesand peaks of the Hawaiian Islands, and in thisrendition appear draped directly on themountains. The clouds are actually about 1000metres above sea level. This type of displayadds the important dimension of elevation tothe study of land use and environmentalprocesses as observed in satellite images,allowing ecologists and planners to assess theeffects of urban development on the sensitiveecosystems in tropical regions


'Beyond the Peaks'

On 2-4 February 2000, the 'ISObeyond the Peaks' workshop washeld in Villafranca del Castillo,Madrid, Spain. This workshop wasthe second in a series initiated withthe successful 'First ISO Workshopon Analytical Spectroscopy', held inOctober 1997, in which 100astronomers gathered in Villafrancato discuss ESA's Infrared SpaceTelescope ISO observations andassociated scientific interpretation,2 years into the ongoing mission.This second workshop took placewith all ISO data having entered thepublic domain. 140 astronomers,more than expected, attended theworkshop, discussing in 38 talksand 50 posters, aspects of thedetailed ISO spectroscopic heritageincluding, among other topics, thecosmic cycle of water and thederivation of an inventory of cosmicices. Many results lead to thedevelopment of more sophisticatedmodels, such as dynamical models forAGB stars, or upper layers of warmmolecular gas in the atmospheres of Mirastars. Representatives of upcoming IRmissions such as SIRTF, SOFIA andASTRO-F were also present.

The Crystalline RevolutionISO's Finding Opens a New ResearchField, 'Astro-Mineralogy'Silicate crystals, the most abundantminerals on Earth, are also found in greatquantities around old stars and inprotoplanetary discs – the discs whereplanets form. This finding, presented at apress conference on the last day of the'Beyond the Peaks' workshop, isconsidered by experts in space chemistryas one of the main results of ESA'sinfrared space telescope, ISO. Silicateminerals were known to be a maincomponent of dust in space, butdetecting them in a crystallised state hasbeen a surprise. It allows the identificationof precise silicates in astronomical objects,which will open a totally new field inastronomy: 'astro-mineralogy'. "This is thecrystalline revolution", said the author,Dutch astronomer Rens Waters ofAmsterdam University.

"It's really fantastic, this possibility ofidentifying the silicates. Before ISOeverybody thought that all silicates inspace were amorphous, without a well-

ordered internal structure; that means youcannot differentiate among the manydifferent silicates existing. Now we can tryto identify them and track their presencein different regions. A whole new researchfield is starting", said Waters, who broughtto the press conference samples ofseveral terrestrial crystalline silicates:olivine and pyroxene, the most commonsilicates on Earth.

Crystals give key clues about the physicalconditions and evolutionary history ofcrystal-bearing objects. The precisemechanisms for crystal-making are nowbeing actively researched in laboratories,although some working-hypotheses arealready being used. For instance, crystalscan be made by heating the material totemperatures above 1300°C and thenslowly cooling it down. Those found so farby ISO are at -170°C, both in stellarenvelopes and in protoplanetary discs.

In the case of the old stars – red giantstars, where crystals are found to accountfor as much as 20% of all the surroundingdust – astronomers think that that the hightemperatures near the star triggered thecrystallisation of the silicates. In theprotoplanetary discs some expertspostulate that electric shocks – likelightning flashes – heated the dust, whichcooled afterwards.

"The crystals detected by ISO in thesediscs have a size of about a thousandth of

a millimetre. They collide with eachother, forming bigger and biggerbodies. Models predict that inabout ten to one hundred millionyears they will make planets",Waters says. "In fact, crystallinesilicates are very common in ourown Solar System. You also havethem in the comet Hale Bopp!".

The reason why crystallinesilicates had not previously beendetected in stars has to do withtheir low temperatures. Coldmaterial emits mostly infrared light,which means an infrared spacetelescope like ESA's ISO wasneeded. The two high-resolutionspectrometers onboard thesatellite, able to detect the'chemical fingerprint' of thecrystals, did the rest.

Astronomers are sure about thediscovery because those chemical

fingerprints, the spectra, can be comparedin laboratories with spectra from crystallinesilicates found on Earth. This method hasdemonstrated the crystalline structure andhas even already allowed the identificationof some of the crystals, such as forsteriteand enstatite. However, crystalline silicatesare a large family and their chemicalsignatures can be very similar; to enlargethe list of precise crystals more work willbe needed, say experts in spacechemistry.

"Crystalline silicates are synthesisedaround the stars; then that dust goes intothe interstellar space, and enriches theraw material out of which more stars andplanets will form. So you would expectcrystals also to be in the interstellarmedium! Crystals will certainly make uslearn a lot...", according to Waters.

"This finding shows that ISO is reallyunveiling the chemistry of the Universe",says ESA astronomer Alberto Salama,chairman of the workshop about ISOresults in spectroscopy held this week atESA's Villafranca station in Madrid wherethe results were presented to the scientificcommunity. "This is becoming more andmore a 'hot field' of research. Initially weintended to organise a modest workshop,but we have had 140 astronomers comingfrom all over the world!". r

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Signatures of crystalline silicate forsterite found by ISO closeto young stars and in comets. Credits: ISO (ESA), SWS & C. Waelkens et al.

AP2000 MillenniumConferenceSummary

The AP2000 MillenniumConference on Antennas andPropagation was held from 9-14 April in Davos, Switzerland. Some 1100 delegates, one thirdfrom overseas, attended theconference, presenting over 900papers in 65 specialised oral andposter sessions. Several shortcourses were also offered to delegates byeminent scientists. Equipment, softwareand books were displayed by industry insome 20 exhibitions. AP2000 is thelargest conference ever organised in thisfield in Europe.

Current work in Antennas and Radio-wavePropagation is driven by new requirementsfor expanding wireless communicationand remote sensing applications.

For mobile communications, multibeamreflector and planar or conformal arrayswith active or semi-active feeding andsmart beam forming, are being developedfor satellites and for cellular base stations.Channel modelling in complex com-munication environments, buildingpenetration and avoidance of interferenceare key topics in mobile propagation.Interactions of microwave with biologicaltissues is also an area of extensiveresearch activity. Concurrent engineeringinvolving antenna, propagation and signalprocessing disciplines is becoming the keyto mobile communication system design.

For wideband multimedia communications,the trend is to use higher frequencies up

into the millimetre-wave range. Thisrequires new propagation models, newimpairment restoration techniques toovercome fading and scintillation at higherfrequencies. Here also, closer coopera-tion between propagation modelling andantenna design is required to developactive fade compensation techniques forsatellite and terrestrial systems, whereantenna gain and power are continuouslyadapted to propagation conditions. Atmillimetre wave frequencies, integratingactive components and radiating elementson the same substrates, some of themwith frequency sensitive (Photonic BandGap), or for multifrequency capability(fractal antennas) is the object ofsustained research activities.

The new concept of stratospheric com-munication relay, and perhaps observationplatforms, also introduces new challengesto propagation and antenna engineers,which are currently being investigated.

In the field of remote sensing, challengingperspectives have been discussed bothfor passive and active instruments. Inparticular, the SMOS sensor, accepted byESA in the framework of the Earth

Explorer Opportunity Missions, willmonitor from space soil moisture,salinity, vegetation biomass andsurface temperature using micro-wave interferometry at L-band.Such a new instrument, with itslarge two-dimensional array poseschallenging antenna engineeringand retrieval problems. Atmos-pheric remote sensing forcommunication and radarapplications is also an expandingfield.

Multifrequency synthetic aperture radarrequires new low-cost printed antennatechnologies, much discussed at theconference. Spaceborne repeat andsingle-pass SAR interferometry opens newperspectives and challenges for digitalelevation mapping, cartography andseismology

Finally, ground penetration radars,involving both antennas and complexpropagation issues, have been extensivelydiscussed at AP2000, mostly for thedetection of buried objects. They are alsobeing considered for planetary observationmissions.

This successful conference has providedESA with precious inputs for its futureR&D in the key areas of antennas, wavepropagation and microwave remotesensing. It has also enhanced the imageof ESA's technical excellence in theantenna and propagation communitiesworld-wide, as well as in the associatedengineering societies.

For technical information on the AP2000conference, please consult the AP2000website: <http://www.estec.esa.nl/AP2000/> or contact: Dr Antoine G. RoedererAP2000 ChairmanESTEC,2200 AG NoordwijkThe Netherlands E-mail: [email protected]

The Proceedings of the conference areavailable on CD-ROM from the ESAPublications website<http://esapub.esa.int> (ESA PublicationsBookshop) or fax +31-71-565-5433. r

Photos of the AP2000 Opening Session

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ESA and Hubble:Changing our VisionIn light of the Hubble Space Telescope’s10th anniversary on 27 April, ESA held apress conference at the Space Telescope-European Coordinating Facility (ST-ECF) inMunich in which the new and fullyEuropean outreach initiative, the'European Space Agency HubbleInformation Centre' was presented andlaunched.

With the astronauts who took part in themost recent Servicing Mission (SM3A) inattendance, ESA presented a completeoverview of Europe’s major contribution tothe HST mission, and reviewed the firstten years of operations and theoutstanding results that have 'changedour vision' of the cosmos.

With this initiative, ESA shows itscommitment to public outreach andto the communication of science.

With an expected life time of 20 years,Hubble is now at the midpoint of its life. It has so far been one of the mostsuccessful scientific space missions, andthe continuous maintenance and upgradingof the observatory through the ServicingMissions makes Hubble’s next ten yearsappear even more promising. r

ESA Brochure-157 '10 Years that Changed ourVision' covers the background and scienceinformation of the Hubble Telescope Project. Itis available from the ESA PublicationsBookshop at <http://esapub.esa.int>

Visit the new 'European Space Agency Hubble Information Centre' at <http://hubble.esa.int>

ERS – ENVISAT SYMPOSIUM

‘Looking Down to Earth in the NewMillenium’

Organised by: ESA and the Chalmers University ofTechnology

16-20 October 2000 – Gothenburg, Sweden

http://www.esa.int/sympo2000

Contacts: – for Website aspects, registration,

information:Barbara Scarda, ESRINtel. +39-06-94180941fax +39-06-94180942E-mail: [email protected]

– for Symposium contents:Gianna Calabresi, ESRINtel. +39-06-94180625fax +39-06-94180552E-mail: [email protected]

– for Local Support:Britt-Marie BoisenChalmers University of Technology,Gothenburg, Swedentel. +46-31-7721840fax +46-31-164513E-mail: [email protected]

in brief - european space agencyglobal timing system (gts) and a radiobiology experiment (called...

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