The Cluster Mission Editorial

Total Page:16

File Type:pdf, Size:1020Kb

The Cluster Mission Editorial INTERNATIONAL SPACE SCIENCE INSTITUTE No 9, June 2002 Published by the Association Pro ISSI The Fourfold Way Through the Magnetosphere: The Cluster Mission Editorial Imagine a lonely spacecraft trav- currently Director of the Inter- Impressum elling through space. Its mission national Space Science Institute in is to probe the value of, say, the Bern and Senior Scientists at the strength of the local magnetic Max Planck Institute for extra- field. Its instruments continuously terrestrial Physics in Garching SPATIUM monitor the field strength and de- (Germany) is one of the fathers of Published by the liver the data to the on-board Cluster. He is also the Principle Association Pro ISSI telecommunication system, which Investigator of the Electron Drift twice a year forwards them to the ground con- Instrument designed to determine trol station on Earth. There, scien- the strength of the local electric tists try to interpret the data. field around the spacecraft. INTERNATIONAL SPACE SCIENCE But now a basic dilemma arises: In November 2001, very shortly INSTITUTE due to the continuous motion and after the commissioning of the Association Pro ISSI temporal evolution of the ambi- Cluster spacecraft G. Paschmann Hallerstrasse 6, CH-3012 Bern ent medium and its boundaries, presented the first results to our Phone ++41 31 631 48 96 the recorded data are a complicat- members. In the mean time, this Fax ++41 31 631 48 97 ed mix. The observer cannot dis- mission has delivered a wealth of tinguish whether the magnetic additional data, which partially President field experienced a change in time could be considered in the present Prof. Hermann Debrunner, or it varied spatially or both hap- revised version of his lecture. We University of Bern pened simultaneously. are very indebted to G. Pasch- Publisher mann for his kind permission to Dr. Hansjörg Schlaepfer, That was the problem faced by publish the present text on the legenda schläpfer wort & bild, the fathers of the European Space fascinating world of magnetic Winkel Agency’s Cluster mission in 1982 fields. Layout intended to exploring the Earth’s Marcel Künzi, marketing · kom- magnetosphere. Their idea was to munikation, CH-8483 Kollbrunn solve the problem by flying a Printing quartet of closely spaced identical Hansjörg Schlaepfer Druckerei Peter + Co dpc spacecraft, since time and space Bern, June 2002 CH-8037 Zurich need a set of three co-ordinates to be defined completely. The in- struments aboard the four space- craft may now take measure- ments at identical times but at different places in space allowing the scientists to work out the rele- vant temporal and spatial charac- teristics of the magnetic field and Front Cover: The aurora is the the other quantities that charac- only visible proof of the Earth’s terize the ambient medium, such magnetosphere. This wonderful as the electric field, and plasma picture shows the glow from out- density, velocity and temperature. bursts of ionic particles from the Sun in the ionosphere. (Credit & The author of the present issue Copyright: Dennis Mammana, of Spatium, Dr. Götz Paschmann, Skyscapes) SPATIUM 9 2 The Fourfold Way Through the Magnetosphere: The Cluster Mission *) Götz Paschmann,International Space Science Institute,Bern and Max Planck Institut für extraterrestrische Physik,Garching Introduction ral evolution. Cluster is the first forward. One should not forget attempt to do this in space, admit- though that because of the com- tedly with only the minimum plex structure of the magnetos- number that can be arranged in phere and the strong interrela- three dimensions, namely four. tionship between its parts, there is The Earth’s magnetosphere has There have previous attempts the danger that spacecraft flying in been investigated by direct in-situ with two spacecraft (ISEE and close formation will miss the measurements since the begin- AMPTE), but with two stations large-scale context. Fortunately, ning of the space age and has one can only infer variations along observations from the ground and turned out to be the site of many the line between the spacecraft, from other spacecraft are available fascinating phenomena and pro- and three stations always form a that serve to fill in this global cesses that must be studied in-situ plane. Thus Cluster is a giant step context. because they are not accessible by remote sensing techniques. Exam- ples are shock formation, magnet- ic reconnection, particle accelera- Interplanetary Magnetic Field tion, wave-particle interaction and Tail Current turbulence. While interesting in their own right, as part of the ex- ploration of the Earth’s environ- ment, they can also guide our Plasma Mantle understanding of similar pro- cesses on the Sun or the distant Magnetotail Northern Lobe universe, places where one can never make in-situ measure- Polar Cusp ments. Figure 1 shows a view of the Plasma Sheet Plasma- Neutral Sheet magnetosphere that emphasizes sphere Current its main features, except for the t bow shock that has been left out n e r for clarity. u r Ring C While much has been learned Magnetopause about the magnetosphere through Solar Magneto- measurements from single satel- pause Field-Aligned Current Current lites, a limitation has been the Wind fundamental inability of a single observer to unambiguously dis- tinguish spatial from temporal changes. The magnetosphere is constantly changing its shape and Figure 1 size, and many of the processes Cutaway view of the Earth’s magnetosphere that identifies the key regions en- countered by Cluster: the solar wind approaching from the left; the magnetopause governing it are known to vary on (yellow surface) that is the outer boundary of the magnetosphere; the polar cusp, a short spatial and temporal scales. funnel-shaped indentation in the magnetopause; the magnetotail, with the hot A solution to this dilemma is a plasma sheet at the centre and the lobes on either side. Thin black lines with arrows fleet of mobile stations, very are the magnetic field lines, dashed lines show plasma flow. The black arrows mark electric current flow. The bow shock that stands in the solar wind ahead of the much like what one does to study magnetopause, and the region in between, the magnetosheath, have been omitted weather patterns and their tempo- for clarity. th *) Pro ISSI lecture, Bern, 8 November 2001 SPATIUM 9 3 The Cluster Spatium Nr. 2. Cluster was not so and successfully launched on two fortunate. Ready for launch in Soyuz-Fregate launchers from Mission 1995, the four spacecraft were de- Baikonur on 16 July and 12 August stroyed when the Ariane 5 rocket 2000, respectively. After extensive exploded during its maiden flight commissioning of the payload, the on 4 June 1996. At first it seemed science phase officially began on that the only remaining option 1 February 2001. was to put together a single space- History craft from the leftover parts, ap- This being a Pro ISSI lecture, I propriately named Phoenix after should point out that several peo- Cluster’s history goes back to the mythical bird that rose from ple associated with ISSI were November 1982, when a group of the ashes. But recognizing the deeply involved in Cluster. Two European scientists proposed the unique importance of the mis- of its directors, Bengt Hultqvist mission. In February 1986 ESA sion, the ESA Science Programme and myself, and a long-time mem- chose Cluster and the Solar and Committee (SPC) on 3 April ber of its Science Committee, Heliospheric Observatory (SOHO) 1997 agreed that three new Gerhard Haerendel, were among as the first “Cornerstone” in its Cluster spacecraft should be built the seven who proposed the mis- Horizon 2000 Science Pro- alongside Phoenix, and thus sion in 1982. Roger Bonnet, then gramme. SOHO was launched in Cluster was reborn. Through a Director of Scientific Programmes December 1995 and has sent back tremendous effort by all involved, at ESA, was the key force behind a stream of exciting data about the fully instrumented satellites the recovery initiative, and Hans the Sun, as vividly described in were rebuilt in only three years Balsiger was chairman of ESA’s ck magnetosheath sho w bo magnetopause Bow shock Polar cusp cusp Auroral zone neutral sheet tra region Plasmas- phere lobes Magnetopause Solar wind Figure 2 Cluster orbit in February, as it cuts through the key regions of the magnetosphere. SPATIUM 9 4 SPC, when the decision to repeat superimposed on a cut of the mag- 10 5 Nominal phase Extension phase Cluster was finally made in April netosphere, and illustrates that 1997. Last but not least, Hans Cluster moves outbound over the 10 4 Peter Schneiter and Contraves northern polar cap, crosses the mag- 10 3 Space had a leading role in the re- netopause and bow shock into the max vival efforts by the industry that solar wind, before recrossing those min 10 2 had built Cluster. It is therefore boundaries in reverse order and cusp only natural that the interpretation moving over the southern polar tail 10 1 of the Cluster measurements will cap back towards perigee. Figure 2 distance [km]Inter-spacecraft Aug-00 01 02 03 04 05 date be one of ISSI’s future workshop applies to February of each year. Figure 4 activities. As the orbit is inertially fixed, it Spacecraft separation distances as rotates around the Earth once a planned for the entire mission. year, as the latter revolves around Orbits and Separations the Sun. As a result, the apogee regular tetrahedron when cross- of the orbit will be located in the ing the major boundaries. The After their successful launch from geomagnetic tail half a year later, separation distances between the Baikonur, the Cluster spacecraft as shown in Figure 3. In the course spacecraft are being changed be- were placed in nearly identical, of the mission Cluster will thus tween 100 km and tens of thou- highly eccentric polar orbits, with encounter the regions of interest sands of km during the mission.
Recommended publications
  • The Van Allen Probes' Contribution to the Space Weather System
    L. J. Zanetti et al. The Van Allen Probes’ Contribution to the Space Weather System Lawrence J. Zanetti, Ramona L. Kessel, Barry H. Mauk, Aleksandr Y. Ukhorskiy, Nicola J. Fox, Robin J. Barnes, Michele Weiss, Thomas S. Sotirelis, and NourEddine Raouafi ABSTRACT The Van Allen Probes mission, formerly the Radiation Belt Storm Probes mission, was renamed soon after launch to honor the late James Van Allen, who discovered Earth’s radiation belts at the beginning of the space age. While most of the science data are telemetered to the ground using a store-and-then-dump schedule, some of the space weather data are broadcast continu- ously when the Probes are not sending down the science data (approximately 90% of the time). This space weather data set is captured by contributed ground stations around the world (pres- ently Korea Astronomy and Space Science Institute and the Institute of Atmospheric Physics, Czech Republic), automatically sent to the ground facility at the Johns Hopkins University Applied Phys- ics Laboratory, converted to scientific units, and published online in the form of digital data and plots—all within less than 15 minutes from the time that the data are accumulated onboard the Probes. The real-time Van Allen Probes space weather information is publicly accessible via the Van Allen Probes Gateway web interface. INTRODUCTION The overarching goal of the study of space weather ing radiation, were the impetus for implementing a space is to understand and address the issues caused by solar weather broadcast capability on NASA’s Van Allen disturbances and the effects of those issues on humans Probes’ twin pair of satellites, which were launched in and technological systems.
    [Show full text]
  • Astronomy & Astrophysics a Hipparcos Study of the Hyades
    A&A 367, 111–147 (2001) Astronomy DOI: 10.1051/0004-6361:20000410 & c ESO 2001 Astrophysics A Hipparcos study of the Hyades open cluster Improved colour-absolute magnitude and Hertzsprung{Russell diagrams J. H. J. de Bruijne, R. Hoogerwerf, and P. T. de Zeeuw Sterrewacht Leiden, Postbus 9513, 2300 RA Leiden, The Netherlands Received 13 June 2000 / Accepted 24 November 2000 Abstract. Hipparcos parallaxes fix distances to individual stars in the Hyades cluster with an accuracy of ∼6per- cent. We use the Hipparcos proper motions, which have a larger relative precision than the trigonometric paral- laxes, to derive ∼3 times more precise distance estimates, by assuming that all members share the same space motion. An investigation of the available kinematic data confirms that the Hyades velocity field does not contain significant structure in the form of rotation and/or shear, but is fully consistent with a common space motion plus a (one-dimensional) internal velocity dispersion of ∼0.30 km s−1. The improved parallaxes as a set are statistically consistent with the Hipparcos parallaxes. The maximum expected systematic error in the proper motion-based parallaxes for stars in the outer regions of the cluster (i.e., beyond ∼2 tidal radii ∼20 pc) is ∼<0.30 mas. The new parallaxes confirm that the Hipparcos measurements are correlated on small angular scales, consistent with the limits specified in the Hipparcos Catalogue, though with significantly smaller “amplitudes” than claimed by Narayanan & Gould. We use the Tycho–2 long time-baseline astrometric catalogue to derive a set of independent proper motion-based parallaxes for the Hipparcos members.
    [Show full text]
  • Transmittal of Geotail Prelaunch Mission Operation Report
    National Aeronautics and Space Administration Washington, D.C. 20546 ss Reply to Attn of: TO: DISTRIBUTION FROM: S/Associate Administrator for Space Science and Applications SUBJECT: Transmittal of Geotail Prelaunch Mission Operation Report I am pleased to forward with this memorandum the Prelaunch Mission Operation Report for Geotail, a joint project of the Institute of Space and Astronautical Science (ISAS) of Japan and NASA to investigate the geomagnetic tail region of the magnetosphere. The satellite was designed and developed by ISAS and will carry two ISAS, two NASA, and three joint ISAS/NASA instruments. The launch, on a Delta II expendable launch vehicle (ELV), will take place no earlier than July 14, 1992, from Cape Canaveral Air Force Station. This launch is the first under NASA’s Medium ELV launch service contract with the McDonnell Douglas Corporation. Geotail is an element in the International Solar Terrestrial Physics (ISTP) Program. The overall goal of the ISTP Program is to employ simultaneous and closely coordinated remote observations of the sun and in situ observations both in the undisturbed heliosphere near Earth and in Earth’s magnetosphere to measure, model, and quantitatively assess the processes in the sun/Earth interaction chain. In the early phase of the Program, simultaneous measurements in the key regions of geospace from Geotail and the two U.S. satellites of the Global Geospace Science (GGS) Program, Wind and Polar, along with equatorial measurements, will be used to characterize global energy transfer. The current schedule includes, in addition to the July launch of Geotail, launches of Wind in August 1993 and Polar in May 1994.
    [Show full text]
  • Planned Yet Uncontrolled Re-Entries of the Cluster-Ii Spacecraft
    PLANNED YET UNCONTROLLED RE-ENTRIES OF THE CLUSTER-II SPACECRAFT Stijn Lemmens(1), Klaus Merz(1), Quirin Funke(1) , Benoit Bonvoisin(2), Stefan Löhle(3), Henrik Simon(1) (1) European Space Agency, Space Debris Office, Robert-Bosch-Straße 5, 64293 Darmstadt, Germany, Email:[email protected] (2) European Space Agency, Materials & Processes Section, Keplerlaan 1, 2201 AZ Noordwijk, Netherlands (3) Universität Stuttgart, Institut für Raumfahrtsysteme, Pfaffenwaldring 29, 70569 Stuttgart, Germany ABSTRACT investigate the physical connection between the Sun and Earth. Flying in a tetrahedral formation, the four After an in-depth mission analysis review the European spacecraft collect detailed data on small-scale changes Space Agency’s (ESA) four Cluster II spacecraft in near-Earth space and the interaction between the performed manoeuvres during 2015 aimed at ensuring a charged particles of the solar wind and Earth's re-entry for all of them between 2024 and 2027. This atmosphere. In order to explore the magnetosphere was done to contain any debris from the re-entry event Cluster II spacecraft occupy HEOs with initial near- to southern latitudes and hence minimise the risk for polar with orbital period of 57 hours at a perigee altitude people on ground, which was enabled by the relative of 19 000 km and apogee altitude of 119 000 km. The stability of the orbit under third body perturbations. four spacecraft have a cylindrical shape completed by Small differences in the highly eccentric orbits of the four long flagpole antennas. The diameter of the four spacecraft will lead to various different spacecraft is 2.9 m with a height of 1.3 m.
    [Show full text]
  • Rumba, Salsa, Smaba and Tango in the Magnetosphere
    ESCOUBET 24-08-2001 13:29 Page 2 r bulletin 107 — august 2001 42 ESCOUBET 24-08-2001 13:29 Page 3 the cluster quartet’s first year in space Rumba, Salsa, Samba and Tango in the Magnetosphere - The Cluster Quartet’s First Year in Space C.P. Escoubet & M. Fehringer Solar System Division, Space Science Department, ESA Directorate of Scientific Programmes, Noordwijk, The Netherlands P. Bond Cranleigh, Surrey, United Kingdom Introduction Launch and commissioning phase Cluster is one of the two missions – the other When the first Soyuz blasted off from the being the Solar and Heliospheric Observatory Baikonur Cosmodrome on 16 July 2000, we (SOHO) – constituting the Solar Terrestrial knew that Cluster was well on the way to Science Programme (STSP), the first recovery from the previous launch setback. ‘Cornerstone’ of ESA’s Horizon 2000 However, it was not until the second launch on Programme. The Cluster mission was first 9 August 2000 and the proper injection of the proposed in November 1982 in response to an second pair of spacecraft into orbit that we ESA Call for Proposals for the next series of knew that the Cluster mission was truly back scientific missions. on track (Fig. 1). In fact, the experimenters said that they knew they had an ideal mission only The four Cluster spacecraft were successfully launched in pairs by after switching on their last instruments on the two Russian Soyuz rockets on 16 July and 9 August 2000. On 14 fourth spacecraft. August, the second pair joined the first pair in highly eccentric polar orbits, with an apogee of 19.6 Earth radii and a perigee of 4 Earth radii.
    [Show full text]
  • Radiation Belt Storm Probes Launch
    National Aeronautics and Space Administration PRESS KIT | AUGUST 2012 Radiation Belt Storm Probes Launch www.nasa.gov Table of Contents Radiation Belt Storm Probes Launch ....................................................................................................................... 1 Media Contacts ........................................................................................................................................................ 4 Media Services Information ..................................................................................................................................... 5 NASA’s Radiation Belt Storm Probes ...................................................................................................................... 6 Mission Quick Facts ................................................................................................................................................. 7 Spacecraft Quick Facts ............................................................................................................................................ 8 Spacecraft Details ...................................................................................................................................................10 Mission Overview ...................................................................................................................................................11 RBSP General Science Objectives ........................................................................................................................12
    [Show full text]
  • Polar Observations of Electron Density Distribution in the Earth's
    c Annales Geophysicae (2002) 20: 1711–1724 European Geosciences Union 2002 Annales Geophysicae Polar observations of electron density distribution in the Earth’s magnetosphere. 1. Statistical results H. Laakso1, R. Pfaff2, and P. Janhunen3 1ESA Space Science Department, Noordwijk, Netherlands 2NASA Goddard Space Flight Center, Code 696, Greenbelt, MD, USA 3Finnish Meteorological Institute, Geophysics Research, Helsinki, Sweden Received: 3 September 2001 – Revised: 3 July 2002 – Accepted: 10 July 2002 Abstract. Forty-five months of continuous spacecraft poten- Key words. Magnetospheric physics (magnetospheric con- tial measurements from the Polar satellite are used to study figuration and dynamics; plasmasphere; polar cap phenom- the average electron density in the magnetosphere and its de- ena) pendence on geomagnetic activity and season. These mea- surements offer a straightforward, passive method for mon- itoring the total electron density in the magnetosphere, with high time resolution and a density range that covers many 1 Introduction orders of magnitude. Within its polar orbit with geocentric perigee and apogee of 1.8 and 9.0 RE, respectively, Polar en- The total electron number density is a key parameter needed counters a number of key plasma regions of the magneto- for both characterizing and understanding the structure and sphere, such as the polar cap, cusp, plasmapause, and auroral dynamics of the Earth’s magnetosphere. The spatial varia- zone that are clearly identified in the statistical averages pre- tion of the electron density and its temporal evolution dur- sented here. The polar cap density behaves quite systemati- ing different geomagnetic conditions and seasons reveal nu- cally with season. At low distance (∼2 RE), the density is an merous fundamental processes concerning the Earth’s space order of magnitude higher in summer than in winter; at high environment and how it responds to energy and momentum distance (>4 RE), the variation is somewhat smaller.
    [Show full text]
  • Equivalence of Current–Carrying Coils and Magnets; Magnetic Dipoles; - Law of Attraction and Repulsion, Definition of the Ampere
    GEOPHYSICS (08/430/0012) THE EARTH'S MAGNETIC FIELD OUTLINE Magnetism Magnetic forces: - equivalence of current–carrying coils and magnets; magnetic dipoles; - law of attraction and repulsion, definition of the ampere. Magnetic fields: - magnetic fields from electrical currents and magnets; magnetic induction B and lines of magnetic induction. The geomagnetic field The magnetic elements: (N, E, V) vector components; declination (azimuth) and inclination (dip). The external field: diurnal variations, ionospheric currents, magnetic storms, sunspot activity. The internal field: the dipole and non–dipole fields, secular variations, the geocentric axial dipole hypothesis, geomagnetic reversals, seabed magnetic anomalies, The dynamo model Reasons against an origin in the crust or mantle and reasons suggesting an origin in the fluid outer core. Magnetohydrodynamic dynamo models: motion and eddy currents in the fluid core, mechanical analogues. Background reading: Fowler §3.1 & 7.9.2, Lowrie §5.2 & 5.4 GEOPHYSICS (08/430/0012) MAGNETIC FORCES Magnetic forces are forces associated with the motion of electric charges, either as electric currents in conductors or, in the case of magnetic materials, as the orbital and spin motions of electrons in atoms. Although the concept of a magnetic pole is sometimes useful, it is diácult to relate precisely to observation; for example, all attempts to find a magnetic monopole have failed, and the model of permanent magnets as magnetic dipoles with north and south poles is not particularly accurate. Consequently moving charges are normally regarded as fundamental in magnetism. Basic observations 1. Permanent magnets A magnet attracts iron and steel, the attraction being most marked close to its ends.
    [Show full text]
  • The Polar Bear Magnetic Field Experiment
    PETER F. BYTHROW, THOMAS A. POTEMRA, LAWRENCE 1. ZANETTI, FREDERICK F. MOBLEY, LEONARD SCHEER, and WADE E. RADFORD THE POLAR BEAR MAGNETIC FIELD EXPERIMENT A primary route for the transfer of solar wind energy to the earth's ionosphere is via large-scale cur­ rents that flow along geomagnetic field lines. The currents, called "Birkeland" or "field aligned," are associated with complex plasma processes that produce ionospheric scintillations, joule heating, and auroral emissions. The Polar BEAR magnetic field experiment, in conjunction with auroral imaging and radio beacon experiments, provides a way to evaluate the role of Birkeland currents in the generation of auroral phenomena. INTRODUCTION 12 Less than 10 years after the launch of the fIrst artifIcial earth satellites, magnetic field experiments on polar orbit­ ing spacecraft detected large-scale magnetic disturbances transverse to the geomagnetic field. I Transverse mag­ netic disturbances ranging from - 10 to 10 3 nT (l nanotesla = 10 - 5 gauss) have been associated with electric currents that flow along the geomagnetic field into and away from the earth's polar regions. 2 These currents were named after the Norwegian scientist Kris­ 18~--~--~-+~~-+-----+--~-r----~6 tian Birkeland who, in the first decade of the twentieth century, suggested their existence and their association with the aurora. Birkeland currents are now known to be a primary vehicle for coupling energy from the solar wind to the auroral ionosphere. Auroral ovals are annular regions of auroral emission that encircle the earth's polar regions. Roughly 3 to 7 0 latitude in width, they are offset - 50 toward midnight from the geomagnetic poles.
    [Show full text]
  • Ariane 501 Incident at Three Levels of Description
    Launch Failures! December 1, 1994! Ariane 501 Incident " Ariane 4 ! 70th flight! at Three Levels of Description! February 19, 1996! Long March 3B ! 1st flight! 501 Report Dates! 501 Launch Events! June 4, 1996! 0 seconds! Ariane 501 ! June 4-6, 1996! H0 - main cryogenic ! 1st flight! Initial reports of the ! engine ignition! incident! 7 seconds! August 12, 1998! Liftoff! Titan 4A ! 36.7 seconds! Backup inertial reference ! 20th flight! June 6 - July 19, 1996! system inoperative due to ! Intermediate reports! numerical overflow in ! August 26, 1998! horizontal velocity! Delta 3 ! 37.2 seconds! Primary inertial reference ! 1st flight ! July 19, 1996! system inoperative due to ! Inquiry Board Report! numerical overflow in ! horizontal velocity! Time! (months)! 37-38 seconds! July 20-26, 1996! Booster and main engine ! Reports based on ! nozzles swivel, rocket veers ! off course and breaks up ! inquiry findings! from aerodynamic loads ! July 27 - September, 1996! 39 seconds! Automatic self-destruct ! Comprehensive reports ! 45 seconds! Time! Time! Range safety officer destruct ! (days)! (secs.)! “High Profit” Documents! Ariane 5 Flight 501 Failure: Report by the Inquiry Board (July 19, 1996)! Inertial Reference Software Error Blamed for Ariane 5 Failure; Defense !Daily (July 24, 1996) ! !!! Software Design Flaw Destroyed Ariane 5; next flight in 1997; ! !Aerospace Daily (July 24, 1996) ! !! Ariane 5 Rocket Faces More Delay; The Financial Times Limited ! !(July 24, 1996) ! Flying Blind: Inadequate Testing led to the Software Breakdown that !Doomed Ariane
    [Show full text]
  • European Space Agency Announces Contest to Name the Cluster Quartet
    European Space Agency Announces Contest to Name the Cluster Quartet. 1. Contest rules The European Space Agency (ESA) is launching a public competition to find the most suitable names for its four Cluster II space weather satellites. The quartet, which are currently known as flight models 5, 6, 7 and 8, are scheduled for launch from Baikonur Space Centre in Kazakhstan in June and July 2000. Professor Roger Bonnet, ESA Director of Science Programme, announced the competition for the first time to the European Delegations on the occasion of the Science Programme Committee (SPC) meeting held in Paris on 21-22 February 2000. The competition is open to people of all the ESA member states. Each entry should include a set of FOUR names (places, people, or things from his- tory, mythology, or fiction, but NOT living persons). Contestants should also describe in a few sentences why their chosen names would be appropriate for the four Cluster II satellites. The winners will be those which are considered most suitable and relevant for the Cluster II mission. The names must not have been used before on space missions by ESA, other space organizations or individual countries. One winning entry per country will be selected to go to the Finals of the competition. The prize for each national winner will be an invitation to attend the first Cluster II launch event in mid-June 2000 with their family (4 persons) in a 3-day trip (including excursions to tourist sites) to one of these ESA establishments: ESRIN (near Rome, Italy): winners from France, Ireland, United King- dom, Belgium.
    [Show full text]
  • Exploring the Solar Poles and the Heliosphere from High Helio-Latitude
    A white paper submitted to ESA for the Voyage 2050 long- term plan ? A journey to the polar regions of a star: Exploring the solar poles and the heliosphere from high helio-latitude Louise Harra ([email protected]) and the solar polar team PMOC/WRC, Dorfstrasse 33, CH-7260 Davos Dorf & ETH-Zürich, Switzerland [Image: Polar regions of major Solar System bodies. Top left, clockwise - Near-surface zonal flows around the solar north pole Bogart et al. (2015); Earth’s changing magnetic field from ESA’s Swarm constellation; Southern polar cap of Mars from ESA’s ExoMars; Jupiter’s poles from the NASA Juno mission; Saturn’s poles from the NASA Cassini mission.] Overview We aim to embark on one of humankind’s great journeys – to travel over the poles of our star, with a spacecraft unprecedented in its technology and instrumentation – to explore the polar regions of the Sun and their effect on the inner heliosphere in which we live. The polar vantage point provides a unique opportunity for major scientific advances in the field of heliophysics, and thus also provides the scientific underpinning for space weather applications. It has long been a scientific goal to study the poles of the Sun, illustrated by the NASA/ESA International Solar Polar Mission that was proposed over four decades ago, which led to the flight of ESA’s Ulysses spacecraft (1990 to 2009). Indeed, with regard to the Earth, we took the first tentative steps to explore the Earth’s polar regions only in the 1800s. Today, with the aid of space missions, key measurements relating to the nature and evolution of Earth’s polar regions are being made, providing vital input to climate-change models.
    [Show full text]