Agent swarms: Cooperation and coordination under stringent communications constraint.

Here we consider the communications tactics appropriate for a group of agents that need to "swarm" together in a challenging communications environment. Swarms are increasingly important in a number of applications, including land, air, sea and space exploration, and their constituent agents could be satellites, drones, or other autonomous vehicles. A particularly difficult problem is to autonomously connect a swarm of agents together in a situation where stringent communication constraints are present, whether due to a need for stealth, restricted on-board power, external requirements to avoid certain broadcast directions, or equipment & hardware limitations.

Surface-to-space atmospheric waves from Hunga Tonga-Hunga Ha'apai eruption.

The January 2022 Hunga Tonga-Hunga Ha'apai eruption was one of the most explosive volcanic events of the modern era, producing a vertical plume that peaked more than 50 km above the Earth. The initial explosion and subsequent plume triggered atmospheric waves that propagated around the world multiple times. A global-scale wave response of this magnitude from a single source has not previously been observed.

Passive, continuous monitoring of carbon dioxide geostorage using muon tomography.

Carbon capture and storage is a transition technology from a past and present fuelled by coal, oil and gas and a planned future dominated by renewable energy sources. The technology involves the capture of carbon dioxide emissions from fossil fuel power stations and other point sources, compression of the CO into a fluid, transporting it and injecting it deep beneath the Earth's surface into depleted petroleum reservoirs and other porous formations. Once injected, the CO must be monitored to ensure that it is emplaced and assimilated as planned and that none leaks back to surface.

A multiresolution inversion for imaging the ionosphere.

Ionospheric tomography has been widely employed in imaging the large-scale ionospheric structures at both quiet and storm times. However, the tomographic algorithms to date have not been very effective in imaging of medium- and small-scale ionospheric structures due to limitations of uneven ground-based data distributions and the algorithm itself. Further, the effect of the density and quantity of Global Navigation Satellite Systems data that could help improve the tomographic results for the certain algorithm remains unclear in much of the literature.

Identification of scintillation signatures on GPS signals originating from plasma structures detected with EISCAT incoherent scatter radar along the same line of sight.

Ionospheric scintillation originates from the scattering of electromagnetic waves through spatial gradients in the plasma density distribution, drifting across a given propagation direction. Ionospheric scintillation represents a disruptive manifestation of adverse space weather conditions through degradation of the reliability and continuity of satellite telecommunication and navigation systems and services (e.g.

Imaging of near-Earth space plasma.

This paper describes the technique of imaging the ionosphere using tomographic principles. It reports on current developments and speculates on the future of this research area. Recent developments in computing and ionospheric measurement, together with the sharing of data via the internet, now allow us to envisage a time when high-resolution, real-time images and 'movies' of the ionosphere will be possible for radio communications planning.