Recent Breakthroughs in RF Photonics for Radar Systems

Radar systems require transmission of very high purity signals. Photonics is now mature enough to achieve analog transmission with very low noise, strong immunity, and wide-bandwidth even in harsh environments. We present our recent developments of optimized optical links dedicated to radar and multifunction systems     

A mission template for exploration and damage mitigation of potential hazard of Near Earth Asteroids

The Apophis Exploratory and Mitigation Platform (AEMP) concept was developed as a prototype mission to explore and potentially deflect the Near Earth Asteroid (NEA) 99942 Apophis. Deflection of the asteroid from the potential 2036 impact will be achieved using a gravity tractor technique, while a permanent deflection, eliminating future threats, will be imparted using a novel albedo manipulation technique. This mission will serve as an archetypal template for future missions to small NEAs and could be adapted to mitigate the threat of collision with other potential Earth-crossing objects.     

Comments on “Effect of wet snow an the null-reference ILSsystem”

The subject paper (July 1993) has raised some issues regarding the probability of the Instrument Landing System (ILS) radiating out-of-tolerance vertical guidance signals. An independent study has substantiated the findings of that paper and adds further concern regarding some FAA ILS snow procedures. The principal conclusions of this paper are: 1) an analysis, based on Walton's discovery of rare snow conditions that cause the null-reference ILS antenna image to disappear, indicates that these conditions can cause out-of-tolerance guidance signals, 2) operation without a monitor of the image radiation can result in signal-in-space guidance signal errors that are significantly beyond the intended limit values, and 3) the integrity of image glide path equipment in snow environments does not satisfy the ILS integrity requirements     

CWLFM Radar for Ship Detection and Identification

Continuous wave lineal frequency modulated (CWLFM) radar presents some interesting advantages for coast surveillance and control as well as low probability of interception (LPI). This paper presents real results obtained with a radar prototype and processed with ISAR techniques. Also, results of an automatic ship identification system applied to simulated ISAR images are exposed. Moreover, radar behavior with unfavorable meteorological conditions is discussed     

Space physics and the teaching of undergraduate electromagnetism

Space physics is not a subject typically found in the undergraduate curriculum, and it is rare even at the graduate level. On the other hand, the basis of space physics is electromagnetism and the motion of charged particles, which are common topics in both the introductory and advanced undergraduate physics curriculum, and examples from space physics can be used to enliven instruction. In this paper, I will discuss various topics commonly found in both introductory and upper-division electricity and magnetism classes where examples from space physics may facilitate student understanding or provide interesting, real-life examples of electromagnetism in action.     

Active learning for advanced students: The Center for Integrated Space Weather Modeling graduate summer school

In recent years there has been considerable research in undergraduate physics education regarding the application to classroom instruction of techniques that are generally referred to as active engagement techniques. However, in very few cases have such pedagogical strategies been applied to graduate-level instruction. In this paper we describe an innovative application of a variety of active engagement techniques at the graduate summer school conducted by the Center for Integrated Space Weather Modeling, a Science and Technology Center funded by the National Science Foundation. We believe that the model presented here can serve as a valuable guide to other group contemplating space physics education at all levels, as well as graduate education generally.     

The Morphologies and Kinematics of Supernova Remnants

We review the major advances in understanding the morphologies and kinematics of supernova remnants (SNRs). Simulations of SN explosions have improved dramatically over the last few years, and SNRs can be used to test models through comparison of predictions with SNRs’ observed large-scale compositional and morphological properties as well as the three-dimensional kinematics of ejecta material. In particular, Cassiopeia A—the youngest known core-collapse SNR in the Milky Way—offers an up-close view of the complexity of these explosive events that cannot be resolved in distant, extragalactic sources. We summarize the progress in tying SNRs to their progenitors’ explosions through imaging and spectroscopic observations, and we discuss exciting future prospects for SNR studies, such as X-ray microcalorimeters.     

GPS autoland considerations

It is pointed out that fully automatic hands-off landing (autoland) capability for commercial aircraft, using the Global Positioning System (GPS), has not been demonstrated, and that ground multipath errors limit vertical positioning accuracy. An evolving integrated-sensor-based architecture for approach and landing, called the tunnel concept, is examined. The precise velocity information available could substantially reduce the vertical accuracy requirement for autoland     

Comparison of global MHD simulation results with actual storm and substorm events

Global MHD models hold the promise of providing a physics-based understanding of magnetospheric structure and dynamics. As such models have become more sophisticated, and computing power has increased, it is now possible to model actual events using solar wind data as a boundary condition. In this paper we present some results MHD simulations of actual storm and substorm events. We will demonstrate that not only can the simulations reproduce details of events, they also are reproducing fundamental aspects of energy coupling between the solar wind and the magnetosphere in such a manner that we can distinguish storms and substorms.