Results 21 to 30 of about 2,184,733 (309)

An initial investigation of the long-term trends in the fluxgate magnetometer (FGM) calibration parameters on the four Cluster spacecraft [PDF]

Geoscientific Instrumentation, Methods and Data Systems, 2014
Over the course of more than 10 years in operation, the calibration parameters of the outboard fluxgate magnetometer (FGM) sensors on the four Cluster spacecraft are shown to be remarkably stable.
L. N. S. Alconcel, P. Fox, P. Brown, T. M. Oddy, E. L. Lucek, C. M. Carr   +5 more
doaj   +2 more sources

Solitary waves observed in the auroral zone: the Cluster multi-spacecraft perspective [PDF]

Nonlinear Processes in Geophysics, 2004
Abstract. We report on recent measurements of solitary waves made by the Wideband Plasma Wave Receiver located on each of the four Cluster spacecraft at 4.5-6.5RE (well above the auroral acceleration region) as they cross field lines that map to the auroral zones.
J. S. Pickett, S. W. Kahler, Li‐Jen Chen, R. L. Huff, O. Santolı́k, Y. V. Khotyaintsev, P. M. E. Décréau, D. Winningham, R. A. Frahm, M. L. Goldstein, G. S. Lakhina, B. T. Tsurutani, B. Lavraud, D. A. Gurnett, M. André, A. N. Fazakerley, A. Balogh, H. Rème   +17 more
openalex   +8 more sources

Intensities and spatiotemporal variability of equatorial noise emissions observed by the Cluster spacecraft [PDF]

Journal of Geophysical Research: Space Physics, 2015
AbstractEquatorial noise (EN) emissions are electromagnetic waves observed in the equatorial region of the inner magnetosphere at frequencies between the proton cyclotron frequency and the lower hybrid frequency. We present the analysis of 2229 EN events identified in the Spatio‐Temporal Analysis of Field Fluctuations (STAFF) experiment data of the ...
F. Němec, O. Santolík, Z. Hrbackova, N. Cornilleau-Wehrlin   +3 more
semanticscholar   +5 more sources

Quasiperiodic emissions observed by the Cluster spacecraft and their association with ULF magnetic pulsations [PDF]

Journal of Geophysical Research: Space Physics, 2013
Quasiperiodic (QP) emissions are electromagnetic waves at frequencies of about 0.5–4 kHz characterized by a periodic time modulation of the wave intensity, with a typical modulation period on the order of minutes. We present results of a survey of QP emissions observed by the Wide‐Band Data (WBD) instruments on board the Cluster spacecraft.
F. Němec, O. Santolík, J. Pickett, M. Parrot, N. Cornilleau-Wehrlin   +4 more
semanticscholar   +5 more sources

Kernel Embedding Approaches to Orbit Determination of Spacecraft Clusters [PDF]

arXiv, 2018
This paper presents a novel formulation and solution of orbit determination over finite time horizons as a learning problem. We present an approach to orbit determination under very broad conditions that are satisfied for n-body problems. These weak conditions allow us to perform orbit determination with noisy and highly non-linear observations such as
Sharma, Srinagesh, Cutler, James W.
arxiv   +3 more sources

Correlation functions of small-scale fluctuations of the interplanetary magnetic field [PDF]

, 2010
The Interplanetary Magnetic Field shows complex spatial and temporal variations. Single spacecraft measurements reveal only a one dimensional section of this rich four dimensional phenomenon. Multi-point measurements of the four Cluster spacecraft provide a unique tool to study the spatiotemporal structure of the field. Using Cluster data we determined
A. Balogh, A. Bigazzi, E. A. Lucek, G. Facskó, G.I. Taylor, H. Rème, J.D. Richardson, J.V. Shebalin, J.W. Bieber, K.T. Osman, K.T. Osman, K.T. Osman, S. Dasso, T.S. Horbury, W.H. Matthaeus, W.H. Matthaeus, Z. Németh, Z. Németh, Z. Németh   +18 more
arxiv   +3 more sources

Ionospheric plasma density structures associated with magnetopause motion: a case study using the Cluster spacecraft and the EISCAT Svalbard Radar [PDF]

, 2004
. On 5 January 2003, the footprint of the Cluster spacecraft, then orbiting in the dayside magnetosphere near the magnetopause, was in the close vicinity of the EISCAT Svalbard Radar (ESR) in the dayside afternoon sector. This configuration made possible
F. Pitout, C. P. Escoubet, E. Lucek
openalex   +2 more sources

Separation of Spacecraft Noise from Geomagnetic Field Observations through Density-Based Cluster Analysis and Compressive Sensing

Journal of Geophysical Research - Space Physics, 2022
The use of magnetometers for space exploration is inhibited by magnetic noise generated by spacecraft electrical systems. Mechanical booms are traditionally used to extend magnetometers away from noise sources.
Alex Paul Hoffmann, M. B. Moldwin
openalex   +2 more sources

ION INJECTION AT QUASI-PARALLEL SHOCKS SEEN BY THE CLUSTER SPACECRAFT

The Astrophysical Journal Letters, 2016
ABSTRACT Collisionless shocks in space plasma are known to be capable of accelerating ions to very high energies through diffusive shock acceleration (DSA). This process requires an injection of suprathermal ions, but the mechanisms producing such a suprathermal ion seed population are still not fully understood. We study acceleration of
A. Johlander, A. Vaivads, Y. Khotyaintsev, A. Retinò, I. Dandouras   +4 more
semanticscholar   +5 more sources

Study of hot flow anomalies using Cluster multi-spacecraft measurements [PDF]

Facsko, G., Trotignon, J. G., Dandouras, I., Lucek, E. A., Daly, P. W. 2010, Advances in Space Research, 45, 541, 2018
Hot flow anomalies (HFAs) were first discovered in the early 1980s at the bow shock of the Earth. In the 1990s these features were studied, observed and simulated very intensively and many new missions focused the attention to this phenomenon again.
Facskó, G., Trotignon, J. G., Dandouras, I., Lucek, E. A., Daly, P. W.   +4 more
arxiv   +6 more sources