Cluster II (spacecraft)
|Operator||European Space Agency in international collaboration with NASA|
|Major contractors||Dornier GmbH (now part of EADS)|
|Launch date||16-Jul-2000 12:39 UT and 09-Aug-2000 11:13 UT|
|Mission duration||12 years, 8 months, and 3 days|
|Mass||1200 kg per satellite|
|Inclination||90 deg (nominal)|
|Orbital period||57 h|
This article is about the current, replacement Cluster mission. For the original, failed mission, see Cluster.
Cluster II is a space mission of the European Space Agency, with NASA participation, to study the Earth's magnetosphere over the course of an entire solar cycle. The mission is composed of four identical spacecraft flying in a tetrahedral formation. A replacement for the original Cluster spacecraft which were lost in a launch failure in 1996, the four Cluster II spacecraft were successfully launched in pairs in July and August 2000 onboard two Soyuz-Fregat rockets from Baikonur. In February 2011, Cluster II celebrated 10 years of successful scientific operations in space. The mission has been extended until December 2012. China National Space Administration/ESA Double Star mission operated alongside Cluster II from 2003 to 2007.
 Mission overview
The four identical Cluster II satellites study the impact of the Sun's activity on the Earth's space environment by flying in formation around Earth. For the first time in space history, this mission is able to collect three-dimensional information on how the solar wind interacts with the magnetosphere and affects near-Earth space and its atmosphere, including aurorae.
The spacecraft are cylindrical (290 x 130 cm, see online 3D model) and are spinning at 15 rotations per minute. After launch, their solar cells provided 224 watts power for instruments and communications. The four spacecraft maneuver into various tetrahedral formations to study the magnetospheric structure and boundaries. The inter-spacecraft distances can be varied from around 17 to 10,000 kilometers (km). The propellant for the maneuvers makes up approximately half of the spacecraft's launch weight.
The highly elliptical orbits of the spacecraft reach a perigee of around 4 RE (Earth radii, where 1 RE = 6371 km) and an apogee of 19.6 RE. Each orbit takes approximately 57 hours to complete. The European Space Operations Centre (ESOC) acquires telemetry and distributes to the online data centers the science data from the spacecraft.
The Cluster mission was proposed to ESA in 1982 and approved in 1986, along with the Solar and Heliospheric Observatory (SOHO). Though the original Cluster spacecraft were completed in 1995, the explosion of the Ariane 5 rocket carrying the satellites in 1996 delayed the mission by four years while the instruments were rebuilt.
On July 16, 2000, a Soyuz-Fregat rocket from the Baikonur Cosmodrome launched two of the replacement Cluster II spacecraft, (Salsa and Samba) into a parking orbit from where they maneuvered under their own power into a 19,000 by 119,000 kilometer orbit with a period of 57 hours. Three weeks later on August 9, 2000 another Soyuz-Fregat rocket lifted the remaining two spacecraft (Rumba and Tango) into similar orbits. Spacecraft 1, Rumba, is also known as the Phoenix spacecraft, since it is largely built from spare parts left over after the failure of the original mission. After commissioning of the payload, the first scientific measurements were made on February 1, 2001.
The ESA ran a competition to name the satellites, which attracted participants from many countries. Ray Cotton from the United Kingdom won with the names Rumba, Tango, Salsa and Samba. Ray's town of residence, Bristol, was awarded with scale models of the satellites in recognition of the naming and connection with the satellites.
Originally planned to last until the end of 2003, the mission has been extended several times. The first extension took the mission from 2004 until 2005, and the second from 2005 to June 2009. The mission has now been extended until end 2014.
 Scientific objectives
Previous single and two-spacecraft missions were not capable of providing the data required to accurately study the boundaries of the magnetosphere. Because the plasma comprising the magnetosphere cannot presently be accessed using remote sensing techniques, satellites must be used to measure it in-situ. Four spacecraft allow scientists make the 3D, time-resolved measurements needed to create a realistic picture of the complex plasma interactions occurring between regions of the magnetosphere and between the magnetosphere and the solar wind.
Each satellite carries a scientific payload of 11 instruments designed to study the small-scale plasma structures in space and time in the key plasma regions: solar wind, bow shock, magnetopause, polar cusps, magnetotail, plasmapause boundary layer and over the polar caps and the auroral zones.
- The bow shock is the region in space between the Earth and the sun where the solar wind decelerates from super- to sub-sonic before being deflected around the Earth. In traversing this region, the spacecraft make measurements which help characterize processes occurring at the bow shock, such as the origin of hot flow anomalies and the transmission of electromagnetic waves through the bow shock and the magnetosheath from the solar wind.
- Behind the bow shock is the thin plasma layer separating the Earth and solar wind magnetic fields known as the magnetopause. This boundary moves continuously due to the constant variation in solar wind pressure. Since the plasma and magnetic pressures within the solar wind and the magnetosphere, respectively, should be in equilibrium, the magnetosphere should be an impenetrable boundary. However, plasma has been observed crossing the magnetopause into the magnetosphere from the solar wind. Cluster's four-point measurements make it possible to track the motion of the magnetopause as well as elucidate the mechanism for plasma penetration from the solar wind.
- In two regions, one in the northern hemisphere and the other in the south, the magnetic field of the Earth is perpendicular rather than tangential to the magnetopause. These polar cusps allow solar wind particles, consisting of ions and electrons, to flow into the magnetosphere. Cluster records the particle distributions, which allow the turbulent regions at the exterior cusps to be characterized.
- The regions of the Earth's magnetic field that are stretched by the solar wind away from the sun are known collectively as the magnetotail. Two lobes that reach past the Moon in length form the outer magnetotail while the central plasma sheet forms the inner magnetotail, which is highly active. Cluster monitors particles from the ionosphere and the solar wind as they pass through the magnetotail lobes. In the central plasma sheet, Cluster determines the origins of ion beams and disruptions to the magnetic field-aligned currents caused by substorms.
- The precipitation of charged particles in the atmosphere creates a ring of light emission around the magnetic pole known as the auroral zone. Cluster measures the time variations of transient particle flows in the region.
 Instrumentation on each Cluster satellite
|1||ASPOC||Active Spacecraft Potential Control experiment||Regulation of spacecraft's electrostatic potential||Enables the measure by PEACE of cold electrons (a few eV temperature), otherwise hidden by spacecraft photoelectrons|
|2||CIS||Cluster Ion Spectroscopy experiment||Ion times-of-flight (TOFs) and energies from 0 to 40 keV||Composition and 3D distribution of ions in plasma|
|3||DWP||Digital Wave Processing instrument||Coordinates the operations of the EFW, STAFF, WBD and WHISPER instruments.||At the lowest level, DWP provides electrical signals to synchronise instrument sampling. At the highest level, DWP enables more complex operational modes by means of macros.|
|4||EDI||Electron Drift Instrument||Electric field E magnitude and direction||E vector, gradients in local magnetic field B|
|5||EFW||Electric Field and Wave experiment||Electric field E magnitude and direction||E vector, spacecraft potential, electron density and temperature|
|6||FGM||Fluxgate Magnetometer||Magnetic field B magnitude and direction||B vector and event trigger to all instruments except ASPOC|
|7||PEACE||Plasma Electron and Current Experiment||Electron energies from 0.0007 to 30 keV||3D distribution of electrons in plasma|
|8||RAPID||Research with Adaptive Particle Imaging Detectors||Electron energies from 30 to 1500 keV, ion energies from 20 to 450 keV||3D distributions of high-energy electrons and ions in plasma|
|9||STAFF||Spatio-Temporal Analysis of Field Fluctuation experiment||Magnetic field B magnitude and direction of EM fluctuations, cross-correlation of E and B||Properties of small-scale current structures, source of plasma waves and turbulence|
|10||WBD||Wide Band Data receiver||Electric field E waveforms and spectrograms of terrestrial plasma waves and radio emissions||Motion of terrestrial fluctuations, e.g. auroral kilometric radiation|
|11||WHISPER||Waves of High Frequency and Sounder for Probing of Density by Relaxation||Electric field E spectrograms of terrestrial plasma waves and radio emissions in the 2–80 kHz range; triggering of plasma resonances by an active sounder.||Source location of waves by triangulation; electron density within the range 0.2–80 cm−3|
 Double Star mission with China
In 2003 and 2004, the China National Space Administration launched the Double Star satellites, TC-1 and TC-2, that worked together with Cluster to make coordinated measurements mostly within the magnetosphere. TC-1 stopped operating on 14 October 2007. Here are three scientific highlights where TC-1 played a crucial role
1. Space is Fizzy
Ion density holes were discovered near the Earth's bow shock that can play a role in bow shock formation. The bow shock is a critical region of space where the constant stream of solar material, the solar wind, is decelerated from supersonic speed to subsonic speed due to the internal magnetic field of the Earth. Full story: http://sci.esa.int/jump.cfm?oid=39559 Echo of this story on CNN: http://www.cnn.com/2006/TECH/space/06/20/space.bubbles/index.html
2. Inner magnetosphere and energetic particles
Chorus Emissions Found Further Away From Earth During High Geomagnetic Activity. Chorus are waves naturally generated in space close to the magnetic equator, within the Earth's magnetic bubble called magnetosphere. These waves play an important role in the creation of relativistic electrons and their precipitation from the Earth's radiation belts. These so-called killer electrons can damage solar panels and electronic equipment of satellites and represent a hazard to astronauts. Therefore, information on their location with respect to the geomagnetic activity is of crucial importance to be able to forecast their impact. Chorus sound file: http://sci.esa.int/science-e/www/object/doc.cfm?fobjectid=38339
3. Magnetotail dynamics
Cluster and Double Star Reveal the Extent of Neutral Sheet Oscillations. For the first time, neutral sheet oscillations observed simultaneously at a distance of tens of thousands of kilometres are reported, thanks to observations by 5 satellites of the Cluster and the Double Star Program missions. This observational first provides further constraint to model this large-scale phenomenon in the magnetotail. Full story: http://sci.esa.int/jump.cfm?oid=38999
"The TC-1 satellite has demonstrated the mutual benefit of, and has fostered, scientific cooperation in space research between China and Europe. We expect even more results when the final archive of high resolution data will be made available to the worldwide scientific community", underlines Philippe Escoubet, Double Star and Cluster mission manager of the European Space Agency.
 Discoveries and mission milestones
- April 15 - From solar activity to stunning aurora (ESA Space Science's image of the week)
- April 10 - Cluster finds source of aurora energy boost
- January 11 - 2013 UK Royal Astronomical Society (RAS) Chapman medal awarded to the Ground-Based Principal Investigator of the Cluster mission
- January 11 - 2013 RAS service award received by the Cluster Joint Science Operations Centre project scientist
- December 18 - The solar wind is swirly
- October 24 - Cluster observes a 'porous' magnetopause
- October 10 - 2012 University of Iowa award for excellence received by the NASA funded PI of the WideBand instrument on the Cluster mission
- August 1 - Cluster looks into waves in the magnetosphere's thin boundaries
- July 2 - Hidden Portals in Earth's Magnetic Field (NASA science cast video)
- June 6 - Origin of particle acceleration in cusps of Earth's magnetosphere uncovered
- March 7 - Earth’s magnetic field provides vital protection
- February 27 - Northern lights mystery may be solved (Space.com)
- February 23 - Surprise Ions (Science News for kids)
- January 26 - Giant veil of cold plasma discovered high above Earth (National Geographic)
- January 24 - Elusive matter found to be abundant far above Earth (AGU press release)
- January 18 - 2012 Royal Astronomical Society Chapman medal awarded to the Principal Investigator of the Cluster PEACE experiment
- September 6 - Ultra fast substorm auroras explained
- August 31 - 40 year old Mariner 5 solar wind problem finds answer
- July 5–10 - Aurora explorer: the Cluster mission exhibit at the Royal Society summer science exhibition 2011
- July 4 - Cluster observes jet braking and plasma heating
- June 30 - 'Dirty hack' restores Cluster mission from near loss
- March 21 - How vital is a planet's magnetic field? New debate rises
- February 5 - Cluster encounters a natural particle accelerator
- January 7 - ESA spacecraft model magnetic boundaries
- November 22 - ESA extends the Cluster mission until December 2014
- October 4 - Cluster helps disentangle turbulence in the solar wind
- September 1 - 10 years of success for Cluster quartet
- July 26 - Cluster makes crucial step in understanding space weather
- July 16 - Cluster's decade of discovery
- July 8 - Announcement of opportunity for Cluster guest investigators
- June 3 - The Cluster archive: more than 1000 users
- April 24 - High-speed plasma jets: origin uncovered
- March 11 - Shocking recipe for 'killer electrons'
- January 20 - Multiple rifts in Earth's magnetic shield
- October 7 - ESA extends the Cluster mission until December 2012
- July 16 - Cluster shows how solar wind is heated at electron scales
- June 18 - Cluster and Double Star: 1000 publications
- April 29 - Monitoring the impact of extreme solar events
- March 25 - Cluster's insight into space turbulence
- February 9 - ESA extends the Cluster mission until the end of 2009
- January 14 - Cluster detects invisible escaping ions
- December 15 - The science of space weather
- December 5 - Looking at Jupiter to understand Earth
- October 17 - Highlights from Cluster-THEMIS workshop
- August 27 - Cluster examines Earth-escaping ions
- August 11 - Electron trapping within reconnection
- June 27 - Beamed radio emission from Earth
- June 9 - Reconnection - Triggered by Whistlers?
- March 7 - Solitons found in the magnetopause
- January 23 - Cluster result impacts future space missions
- December 6 - Cluster explains nightside ion beams
- November 21 - Cluster captures the impact of a Coronal Mass Ejection
- November 9 - Cluster probes generalized Ohm's law in space 
- October 22 - Cluster monitors convection cells over the polar caps
- September 11 - Cluster and Double Star pinpoint the source of bright aurorae
- July 26 - Cluster helps reveal how the Sun shakes the Earth's magnetic field
- June 29 - Cluster unveils a new 3D vision of magnetic reconnection
- June 21 - Formation flying at closest-ever separation
- May 11 - Cluster reveals the reformation of the Earth's bow shock
- April 12 - Cluster finds new clues on what triggers space tsunamis
- March 26 - First direct evidence in space of magnetic reconnection in turbulent plasma
- March 12 - A leap forward in probing magnetic reconnection in space
- February 9 - New insights in the auroral electrical circuit revealed by Cluster
- December 29 - 1000th Orbit for the Cluster Mission
- December 6 - Cluster finds magnetic reconnection within giant swirls of plasma
- November 13 - Cluster takes a new look at the plasmasphere
- October 5 - Double Star and Cluster witness pulsated reconnection for several hours
- August 24 - Cluster links magnetic substorms and Earthward directed high-speed flows
- July 18 - Magnetic heart of a 3D reconnection event revealed by Cluster
- June 20 - Space is fizzy
- May 19 - New Microscopic Properties of Magnetic Reconnection Derived by Cluster
- March 30 - Cluster and Double Star reveal the extent of neutral sheet oscillations
- February 24 - Cluster reveals fundamental 3-D properties of magnetic turbulence
- February 1 - The Cluster Active Archive goes live
- January 11 - Cover of Nature Magazine: Feel the Force
- December 22 - Cluster helps to protect astronauts and satellites against killer electrons
- September 21 - Double Star and Cluster observe first evidence of crustal cracking
- August 10 - From ‘macro’ to ‘micro’ – turbulence seen by Cluster
- July 28 - First direct measurements of the ring current
- July 14 - Five years of formation flying with Cluster
- April 28 - Calming effect of a solar storm
- February 18 - Cluster will become the first multi-scale mission
- February 4 - Direct observation of 3D magnetic reconnection
- December 12 - Cluster determines the spatial scale of high speed flows in the magnetotail
- November 24 Four-point observations of solar wind discontinuities
- September 17 - Cluster locates the source of non-thermal terrestrial continuum radiation by triangulation
- August 12 - Cluster finds giant gas vortices at the edge of Earth's magnetic bubble
- June 23 - Cluster discovers internal origin of the plasma sheet oscillations
- May 13 - Cluster captures a triple cusp
- April 5 - First attempt to estimate Earth's bow shock thickness
- 2003.12.03 - Cracks in Earth's magnetic shield (NASA website)
- 2003.06.29 - Multi-point observations of magnetic reconnection
- 2003.05.20 - ESA's Cluster solves auroral puzzle
- 2003.01.29 - Bifurcation of the tail current
- 2003.01.28 - Electric current measured in space for the first time
- 2002.12.29 - Thickness of the tail current sheet estimated in space for the first time
- 2002.10.01 - Telescopic/Microscopic view of a substorm
- 2001.12.11 - Cluster quartet probes the secrets of the black aurora
- 2001.10.31 - First measurements of density gradients in space
- 2001.10.09 - Double cusp observed by Cluster
- 2001.02.01 - Official start of scientific operations
- Escoubet, C.P., R. Schmidt and M.L. Goldstein (1997). "Cluster - Science and Mission Overview". Space Sci. Rev. 79: 11–32. Bibcode:1997SSRv...79...11E. doi:10.1023/A:1004923124586.
- Escoubet, C.P., M. Fehringer and M. Goldstein (2001). "The Cluster mission". Ann. Geophys. 19 (10/12): 1197–1200. Bibcode:2001AnGeo..19.1197E. doi:10.5194/angeo-19-1197-2001.
- Paschmann, G., S.J. Schwartz, C.P. Escoubet, S. Haaland, ed. (2005). Outer Magnetospheric Boundaries: Cluster Results. reprinted from Space Sci. Rev., 118, 1-4, Springer, Berlin. pp. 1–434.
- Taylor, M., C.P. Escoubet, H. Laakso, A. Masson, M. Goldstein (2010). "The Cluster Mission: Space Plasma in Three Dimensions". In H. Laakso et al. (eds.). The Cluster Active Archive. Astrophys. & Space Sci. Proc., Springer. pp. 309–330.
 Selected publications
All 2199 publications related to the Cluster and the Double Star missions (count as of 28 February 2013) can be found on the publication section of the ESA Cluster mission website
- "Cluster II operations". European Space Agency. Retrieved 29 November 2011.
- Cao, J., Y. Ma, G. Parks, H. Rème, I. Dandouras, and T. Zhang (2013). "Kinetic analysis of the energy transport of bursty bulk flows in the plasma sheet". J. Geophys. Res. Space Physics 118 (1): 313–320. Bibcode:2013JGRA..118..313C. doi:10.1029/2012JA018351.
- Perri, S., M.L. Goldstein, J.C. Dorelli and F. Sahraoui (2012). "Detection of small scale structures in the dissipation regime of solar wind turbulence". Phys. Rev. Lett. 109 (19). Bibcode:2012PhRvL.109s1101P. doi:10.1103/PhysRevLett.109.191101.
- Hwang, K.-J. et al. (2012). "The first in situ observation of Kelvin-Helmholtz waves at high-latitude magnetopause during strongly dawnward interplanetary magnetic field conditions". J. Geophys. Res. 117: A08233. Bibcode:2012JGRA..11708233H. doi:10.1029/2011JA017256.
- Norgren, C. et al. (2012). "Lower hybrid drift waves: space observations". Physical Review Letters 109 (5): 55001. Bibcode:2012PhRvL.109e5001N. doi:10.1103/PhysRevLett.109.055001.
- Nykyri, K., et al. (2012). "On the origin of high-energy particles in the cusp diamagnetic cavity". Journal of Atmospheric and Solar-Terrestrial Physics (Special Issue on Physical Process in the Cusp: Plasma Transport and Energization). doi:10.1016/j.jastp.2011.08.012.
- Wei, Y., et al. (2012). "Enhanced atmospheric oxygen outflow on Earth and Mars driven by a corotating interaction region". J. Geophys. Res. 117 (A16): 3208. Bibcode:2012JGRA..11703208W. doi:10.1029/2011JA017340. Unknown parameter
- Egedal, J., et al. (2012). "Large-scale electron acceleration by parallel electric fields during magnetic reconnection". Nature Phys. Bibcode:2012NatPh...8..321E. doi:10.1038/nphys2249.
- André, M. and C.M. Cully (2 2012). "Low-energy ions: A previously hidden solar system particle population, in press,". Geophys. Res. Lett. 39 (3). Bibcode:2012GeoRL..3903101A. doi:10.1029/2011GL050242.
- Shay, M.A., et al. (2011). "Super-Alfvénic Propagation of Substorm Reconnection Signature and Poynting Flux". Physical Review Letters 107 (6): 065001. arXiv:1104.0922. Bibcode:2011PhRvL.107f5001S. doi:10.1103/PhysRevLett.107.065001.
- Turner, A.J. et al. (2011). "Nonaxisymmetric Anisotropy of Solar Wind Turbulence". Physical Review Letters 107 (9): 095002. arXiv:1106.2023. Bibcode:2011PhRvL.107i5002T. doi:10.1103/PhysRevLett.107.095002.
- Khotyaintsev, Y. et al. (2-11). "Plasma Jet Braking: Energy Dissipation and Nonadiabatic Electrons". Physical Review Letters 106 (16): 165001. Bibcode:2011PhRvL.106p5001K. doi:10.1103/PhysRevLett.106.165001.
- Marklund, G.T. et al. (2011). "Altitude distribution of the auroral acceleration potential determined from Cluster satellite data at different heights". Physical Review Letters 106 (5): 055002. Bibcode:2011PhRvL.106e5002M. doi:10.1103/PhysRevLett.106.055002.
- Echim, M. et al. (2011). "Comparative investigation of the terrestrial and Venusian magnetopause: Kinetic modeling and experimental observations by Cluster and Venus Express". Planet. Space Sci., in press. Bibcode:2011P&SS...59.1028E. doi:10.1016/j.pss.2010.04.019.
- Sahraoui, F. et al. (2010). "Three dimensional anisotropic k spectra of turbulence at subproton scales in the solar wind". Physical Review Letters 105 (13): 131101. Bibcode:2010PhRvL.105m1101S. doi:10.1103/PhysRevLett.105.131101.
- Masson, A., et al. (2011), "A decade revealing the Sun-Earth connection in three dimensions", EOS Trans. 92 (1): 4, Bibcode:2011EOSTr..92Q...4M, doi:10.1029/2011EO010007
- Kistler, L.M. et al. (2010). "Cusp as a source for oxygen in the plasma sheet during geomagnetic storms". J. Geophys. Res. 115: A03209. Bibcode:2010JGRA..11503209K. doi:10.1029/2009JA014838.
- Yuan, Z. et al. (2010). "Link between EMIC waves in a plasmaspheric plume and a detached sub-auroral proton arc with observations of Cluster and IMAGE satellites". Geophys. Res. Lett. 37 (7): L07108. Bibcode:2010GeoRL..3707108Y. doi:10.1029/2010GL042711.
- Laakso, H. et al., ed. (2010). The Cluster Active Archive - Studying the Earth's Space Plasma Environment. Astrophys. & Space Sci. Proc. series, Springer. pp. 1–489. doi:10.1007/978-90-481-3499-1.
- Hietala, H. et al. (2009). "Supermagnetosonic jets behind a collisionless quasiparallel shock". Physical Review Letters 103 (24): 245001. arXiv:0911.1687. Bibcode:2009PhRvL.103x5001H. doi:10.1103/PhysRevLett.103.245001.
- Zong, Q.-G. et al. (2009). "Energetic electron response to ULF waves induced by interplanetary shocks in the outer radiation belt". Journal of Geophysical Research 114: A10204. Bibcode:2009JGRA..11410204Z. doi:10.1029/2009JA014393.
- Dunlop, M. et al. (2009). "Reconnection at High Latitudes: Antiparallel Merging". Physical Review Letters 102 (7): 075005. Bibcode:2009PhRvL.102g5005D. doi:10.1103/PhysRevLett.102.075005.
- Sahraoui, F. et al. (2009). "Evidence of a cascade and dissipation of solar-wind turbulence at the electron gyroscale". Physical Review Letters 102 (23): 231102. Bibcode:2009PhRvL.102w1102S. doi:10.1103/PhysRevLett.102.231102.
- Dandouras, I. et al. (2009). "Magnetosphere response to the 2005 and 2006 extreme solar events as observed by the Cluster and Double Star spacecraft". Adv. Space Res. 43 (23): 618–623. Bibcode:2009AdSpR..43..618D. doi:10.1016/j.asr.2008.10.015.
- Yordanova, E. et al. (2008). "Magnetosheath plasma turbulence and its spatiotemporal evolution as observed by the Cluster spacecraft". Physical Review Letters 100 (20): 205003. Bibcode:2008PhRvL.100t5003Y. doi:10.1103/PhysRevLett.100.205003.
- Engwall, E. et al. (2009). "Magnetosheath plasma turbulence and its spatiotemporal evolution as observed by the Cluster spacecraft". Nature Geosci. 2 (1): 24–27. Bibcode:2009NatGe...2...24E. doi:10.1038/ngeo387.
- Eastwood, J. et al. (2008). "The science of space weather". Phil. Trans. R. Soc. A 366 (1884): 4489–4500. Bibcode:2008RSPTA.366.4489E. doi:10.1098/rsta.2008.0161. PMID 18812302.
- Kronberg, E. et al. (2008). "Comparison of periodic substorms at Jupiter and Earth". J. Geophys. Res. 113: A04212. Bibcode:2008JGRA..11304212K. doi:10.1029/2007JA012880.
- Nilsson, H. et al. (2008). "An assessment of the role of the centrifugal acceleration mechanism in high altitude polar cap oxygen ion outflow". Ann. Geophs. 26: 145–157. Bibcode:2008AnGeo..26..145N. doi:10.5194/angeo-26-145-2008.
- He, J.-S. et al. (2008). "Electron trapping around a magnetic null". Geophys. Res. Lett. 35 (14): L14104. Bibcode:2008GeoRL..3514104H. doi:10.1029/2008GL034085.
- He, J.-S. et al. (2008). "A magnetic null geometry reconstructed from Cluster spacecraft observations". J. Geophys. Res. 113: A05205. Bibcode:2008JGRA..11305205H. doi:10.1029/2007JA012609.
- Mutel, R.L. et al. (2008). "Cluster multispacecraft determination of AKR angular beaming". Geophys. Res. Lett. 35 (7): L07104. arXiv:0803.0078. Bibcode:2008GeoRL..3507104M. doi:10.1029/2008GL033377.
- Wei, X.H. et al. (2007). "Cluster observations of waves in the whistler frequency range associated with magnetic reconnection in the Earth’s magnetotail". J. Geophys. Res. 112: A10225. Bibcode:2007JGRA..11210225W. doi:10.1029/2006JA011771.
- Trines, R. et al. (2007). "Spontaneous Generation of Self-Organized Solitary Wave Structures at Earth's Magnetopause". Physical Review Letters 99 (20): 205006. Bibcode:2007PhRvL..99t5006T. doi:10.1103/PhysRevLett.99.205006.
- Phan, T. et al. (2007). "Evidence for an Elongated (>60 Ion Skin Depths) Electron Diffusion Region during Fast Magnetic Reconnection". Physical Review Letters 99 (25): 255002. Bibcode:2007PhRvL..99y5002P. doi:10.1103/PhysRevLett.99.255002.
- Grigorenko, E.E. et al. (2007). "Spatial-Temporal characteristics of ion beamlets in the plasma sheet boundary layer of magnetotail". J. Geophys. Res. 112 (A5): A05218. Bibcode:2007JGRA..11205218G. doi:10.1029/2006JA011986.
- Lavraud, B. et al. (2007). "Strong bulk plasma acceleration in Earth's magnetosheath: A magnetic slingshot effect?". Geophys. Res. Lett. 34 (14): L14102. Bibcode:2007GeoRL..3414102L. doi:10.1029/2007GL030024.
- Rosenqvist, L.et al. (2007). "An unusual giant spiral arc in the polar cap region during the northward phase of a Coronal Mass Ejection". Ann. Geophys. 25 (2): 507–517. Bibcode:2007AnGeo..25..507R. doi:10.5194/angeo-25-507-2007.
- Lui, A.T.Y. et al. (2007). "Breakdown of the frozen-in condition in the Earth's magnetotail". J. Geophys. Res. 112 (A4): A04215. Bibcode:2007JGRA..11204215L. doi:10.1029/2006JA012000.
- Haaland, S.E. et al. (2007). "High-latitude plasma convection from Cluster EDI measurements: method and IMF-dependence". Ann. Geophys. 25 (1): 239–253. Bibcode:2007AnGeo..25..239H. doi:10.5194/angeo-25-239-2007.
- Förster, M. et al. (2007). "High-latitude plasma convection from Cluster EDI: variances and solar wind correlations". Ann. Geophys. 25 (7): 1691–1707. Bibcode:2007AnGeo..25.1691F. doi:10.5194/angeo-25-1691-2007.
- Sergeev, V. et al. (2007). "Strong bulk plasma acceleration in Earth's magnetosheath: A magnetic slingshot effect?". Geophys. Res. Lett. 34: L02103. Bibcode:2007GeoRL..3402103S. doi:10.1029/2006GL028452.
- Rae, J. et al. (2005). "Evolution and characteristics of global Pc5 ULF waves during a high solar wind speed interval". J. Geophys. Res. 110: A12211. Bibcode:2005JGRA..11012211R. doi:10.1029/2005JA011007.
- Zong, Q.-G. et al. (2007). "Ultralow frequency modulation of energetic particles in the dayside magnetosphere". Geophys. Res. Lett. 34 (12): L12105. Bibcode:2007GeoRL..3412105Z. doi:10.1029/2007GL029915.
- Xiao,C.J. et al. (2007). "Satellite observations of separator-line geometry of three-dimensional magnetic reconnection". Nature Phys. 3 (9): 603–607. arXiv:0705.1021. Bibcode:2007NatPh...3..609X. doi:10.1038/nphys650.
- Lobzin, V.V. et al. (2007). "Ultralow frequency modulation of energetic particles in the dayside magnetosphere". Geophys. Res. Lett. 34 (5): L05107. Bibcode:2007GeoRL..3405107L. doi:10.1029/2006GL029095.
- Lui, A.T.Y.et al. (2006). "Cluster observation of plasma flow reversal in the magnetotail during a substorm". Ann. Geophys. 24 (7): 2005–2013. Bibcode:2006AnGeo..24.2005L. doi:10.5194/angeo-24-2005-2006.
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