80 research outputs found
Radio Aurora Explorer: Mission science and radar system
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95507/1/rds5936.pd
Radar and rocket comparison of UHF radar scattering from auroral electrojet irregularities: Implications for a nanosatellite radar
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95174/1/jgra19910.pd
Space-Time Projection Optical Tomography: Search Space and Orbit Determination
In a companion article, we discussed the radiometric sensitivity and
resolution of a new passive optical sensing technique, Space-Time Projection
Optical Tomography (SPOT), to detect and track sub-cm and larger space debris
for Space Situational Awareness. SPOT is based on the principle that long
synthetic exposure can be achieved if the phase-space trajectory of a
hypothetical point-source is precisely predictable within a very wide telescope
field-of-view, which is the case for orbiting debris. This article discusses
the computational search space for debris mining as well as a recursive
measure-and-fit algorithm based on a generalized Hough transform for orbit
determination.Comment: Space Situational Awarenes
Investigating Coherence among Turkish Elementary Science Teachers’ Teaching Belief Systems, Pedagogical Content Knowledge and Practice
This study investigated comprehensive science teaching belief systems and their relation to science teachers’ pedagogical content knowledge and teaching practices. Rokeach’s (1968) belief system was used as a framework for representing the hierarchy among in-service teachers’ teaching beliefs. This study employed a multiple case study design with three in-service science teachers. Cases were selected based on participant’s personal epistemology. Data were collected through interviews and classroom observations. Content analyses showed that when science teachers presented characteristics of autonomous self-construal more than related self-construal, they had a more advanced personal epistemology. In addition, these beliefs shaped participants’ conceptions of teaching and learning science as well as self-efficacy beliefs, knowledge and practice. Given these results, it is important for social psychologists to collaborate with science teachers to support their self-construa
Magnetic Sensor Calibration and Residual Dipole Characterization for Application to Nanosatellites
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/83632/1/AIAA-2010-7518-617.pd
First measurements of radar coherent scatter by the Radio Aurora Explorer CubeSat
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95350/1/grl29342.pd
Radio Aurora Explorer: A Mission Overview
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140647/1/1.a32436.pd
Magnetosphere-Ionosphere Coupling Through E-region Turbulence: Anomalous Conductivities and Frictional Heating
Global magnetospheric MHD codes using ionospheric conductances based on
laminar models systematically overestimate the cross-polar cap potential during
storm time by up to a factor of two. At these times, strong DC electric fields
penetrate to the E region and drive plasma instabilities that create
turbulence. This plasma density turbulence induces non-linear currents, while
associated electrostatic field fluctuations result in strong anomalous electron
heating. These two effects will increase the global ionospheric conductance.
Based on the theory of non-linear currents developed in the companion paper,
this paper derives the correction factors describing turbulent conductivities
and calculates turbulent frictional heating rates. Estimates show that during
strong geomagnetic storms the inclusion of anomalous conductivity can double
the total Pedersen conductance. This may help explain the overestimation of the
cross-polar cap potentials by existing MHD codes. The turbulent conductivities
and frictional heating presented in this paper should be included in global
magnetospheric codes developed for predictive modeling of space weather.Comment: 13 pages, 5 figures, 2nd of two companion paper
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