Search Publications
Curlometer Technique and Applications
Eastwood, J. P.; Dunlop, M. W.; Shen, C. +9 more
We review the range of applications and use of the curlometer, initially developed to analyze Cluster multi-spacecraft magnetic field data; but more recently adapted to other arrays of spacecraft flying in formation, such as MMS small-scale, 4-spacecraft configurations; THEMIS close constellations of 3-5 spacecraft, and Swarm 2-3 spacecraft config…
The Polar Cusp Seen by Cluster
Pitout, F.; Bogdanova, Y. V.
The investigation of the magnetospheric polar cusps was one of the main objectives of the Cluster mission. The four satellites have crossed those regions numerous times over the years and, with their suitable instrumentation, favorable orbits, and unique multipoint measurements, many aspects of the cusp have been unveiled. The first of those is it…
Electrostatic Solitary Waves in the Earth's Bow Shock: Nature, Properties, Lifetimes, and Origin
Russell, C. T.; Bale, S. D.; Khotyaintsev, Y. +10 more
We present a statistical analysis of >2,100 bipolar electrostatic solitary waves (ESWs) collected from 10 quasi-perpendicular Earth's bow shock crossings by Magnetospheric Multiscale spacecraft. We developed and implemented a correction procedure for reconstruction of actual electric fields, velocities, and other properties of ESW, whose spatia…
Classifying the Magnetosheath Behind the Quasi-Parallel and Quasi-Perpendicular Bow Shock by Local Measurements
Nilsson, H.; Karlsson, T.; Raptis, S. +1 more
We investigate and evaluate the possibility of using local magnetosheath measurements to classify the plasma according to upstream conditions. In order to do this, we use simultaneous measurements from the Cluster spacecraft from time intervals when one of them is located in the solar wind, and the other in the magnetosheath. In particular, we stu…
An Unexpected Whistler Wave Generation Around Dipolarization Front
Wang, Z.; Chen, L.; Zhang, Y. +8 more
Dipolarization front (DF)—a sharp boundary separating hot tenuous plasmas from cold dense plasmas—is followed by a strong Bz region, which is termed flux pileup region (FPR) or dipolarizing flux bundle (DFB). Using 9 year (2001-2009) Cluster data, we show that the FPR hosts whistler waves because of the pancake distribution of electrons…
Quantifying the Lobe Reconnection Rate During Dominant IMF By Periods and Different Dipole Tilt Orientations
Østgaard, N.; Reistad, J. P.; Laundal, K. M. +5 more
Lobe reconnection is usually thought to play an important role in geospace dynamics only when the Interplanetary Magnetic Field (IMF) is mainly northward. This is because the most common and unambiguous signature of lobe reconnection is the strong sunward convection in the polar cap ionosphere observed during these conditions. During more typical …
Ion Outflow and Escape in the Terrestrial Magnetosphere: Cluster Advances
Dandouras, Iannis
Cluster was the first mission in the terrestrial magnetosphere to involve four spacecraft in a tetrahedral configuration, providing three-dimensional measurements of the space plasma parameters. Cluster was also equipped with a very comprehensive instrumentation, allowing the measurement of the ion populations outflowing from the ionosphere, their…
Cluster After 20 Years of Operations: Science Highlights and Technical Challenges
Escoubet, C. P.; Bogdanova, Y. V.; Goldstein, M. L. +7 more
The Cluster mission was the first constellation using four identical spacecraft to study Sun-Earth connection plasma processes. Using four spacecraft in a tetrahedron shape, it could measure, for the first time, 3D quantities such as electrical currents, plasma gradients or divergence of the electron pressure tensor and 3D structures such as bound…
Propagation of Ultralow Frequency Waves from the Ion Foreshock into the Magnetosphere During the Passage of a Magnetic Cloud
Pfau-Kempf, Yann; Ganse, Urs; Battarbee, Markus +12 more
We have examined the properties of ultralow frequency (ULF) waves in space (the ion foreshock, magnetosheath, and magnetosphere) and at dayside magnetometer stations (L = 1.6-6.5) during Earth's encounter with a magnetic cloud in the solar wind, which is characterized by magnetic fields with large magnitudes (∼14 nT) and small cone angles (∼30°). …
Reconstructing Substorms via Historical Data Mining: Is It Really Feasible?
Sitnov, M. I.; Tsyganenko, N. A.; Stephens, G. K. +4 more
The evolution of the low-latitude magnetosphere over the substorm cycle is reconstructed based on a new high-resolution 3D representation of the magnetic field and nearest-neighbor data mining. The study covers radial distances 2.5-25 RE and employs a record-large pool of spacecraft data taken during 1995-2019. The magnetospheric state …