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An Investigation of Turbulence and Intermittency in the High-Latitude Ionosphere: A Multi Case Study
(Master thesis; Mastergradsoppgave, 2024-06-03)High-latitude electron density irregularities can affect technology such as the Global Navigation Satellite Services (GNSS) by degrading radio signals. These irregularities are not fully understood. In this work we investigate turbulence and intermittency in varying regions of the high- latitude ionosphere using the structure function, empirical flatness and probability density function. Our ... -
Dual Radar Detections of Meteors Using Calibrated EISCAT UHF Data
(Mastergradsoppgave; Master thesis, 2024-06-03)The atmosphere of Earth experiences a continuous entry of particles of various sizes originating from several sources. Meteoroids, which are called meteors when entering the atmosphere, are particles that can be measured by radars through scattering off the meteor head plasma which forms around the meteor. These measurements can give information on the processes the meteor undergoes as it travels ... -
Investigation into the photon interaction of small mesospheric dust and its impact on the ionospheric charge balance
(Mastergradsoppgave; Master thesis, 2024-05-31)This thesis investigates the charging mechanisms of nano-sized meteoric smoke particles (MSP) in the mesosphere, with a particular focus on the photoionization and photodetachment processes on MSP assuming different materials. The study begins with three theoretical chapters that lay the ground- work for understanding relevant topics like the atmospheric region in question, MSP, the solar ... -
Pulsating Aurora: Optical observations and modelling of the time-variation of ionospheric response to precipitation of pitch-angle-scattered electrons from the magnetosphere
(Mastergradsoppgave; Master thesis, 2024-01-29)This thesis explores the mechanisms governing pulsating auroras by combining observational analysis with theoretical simulations using the AURORA model. The AURORA model simulates electron transport and ionospheric responses, playing a key role in replicating the abrupt onset precipitation of electrons from source altitudes at 3RE, 4.4RE, 6.1RE, and 7.6RE. Eight events of pulsating aurora were ... -
Kelvin-Helmholtz versus Gradient drift instability: which one "wins" in the high latitude ionosphere?
(Mastergradsoppgave; Master thesis, 2024-01-14)The high latitude ionosphere is highly irregular, which is caused by plasma patches, flow shears and electron precipitation. These causes are not well understood, but it is thought to be three sources to these irregularities: density gradients, arcs/flow channels and electron precipitation. It is speculated that there are two main mechanisms for the formation of these irregularities. These mechanisms ... -
Analysis of dust impacts observed with the Radio Plasma Wave instrument onboard ESA’s Solar Orbiter
(Master thesis; Mastergradsoppgave, 2023-12-15)Dust particles are one of the major constituents of the interplanetary medium in our solar system. They are presumably formed by fragmentation processes of meteoroids and for a certain range of sizes and parameters the dust particles move radially outwards from the Sun. The Radio plasma Wave (RPW) instrument on Solar Orbiter can measure dust particles that impact the spacecraft. By measuring the ... -
On the Distribution of Meteoric Smoke Particles above Andøya, Norway, and Estimated Collection During a Summer Rocket Campaign
(Master thesis; Mastergradsoppgave, 2023-12-21)As meteoroids enter the Earth’s atmosphere, the majority will fully evaporate in the altitude region 70–110 km, due to the frictional heating from atmospheric interactions. The evaporated material is thought to re-condense and coagulate into nanometer sized particles called meteoric smoke particles (MSP). These particles are thought to be a central component in the formation of noctilucent clouds ... -
The effect of a water-ice mantle on dust trajectories in the Kuiper belt
(Mastergradsoppgave; Master thesis, 2023-07-12)The New Horizons spacecraft has travelled through the Solar System and has reached a distance of 55 AU as of 2023. For one of the first times, the dust flux in the outer Solar System has been measured, using the instrument Student Dust Counter (SDC) onboard New Horizons. Between 30 and 50 AU is the Kuiper belt, which is a disk consisting of icy objects. These objects can undergo collisions, causing ... -
Natural occuring oil seepages as a consequence of bottom trawling?
(Mastergradsoppgave; Master thesis, 2023-05-31)Bottom trawling is used to capture fish species that live in the seabed. The damage on the seabed trawling causes has been discussed for many years. This thesis aims to investigate whether bottom trawling for sand eels can be a cause for some of the detected oil seepages in the North Sea. We investigated this using manual delineation of oil seepages in Synthetic Aperture Radar (SAR) satellite ... -
A new Method for Estimating 3-Dimensional Ionospheric Currents from Ground-Based Magnetometers
(Mastergradsoppgave; Master thesis, 2022-07-17)The ionosphere is a region of the upper atmosphere where a significant rate of photo-ionisation from solar ultraviolet radiation cause an increased plasma density. In this region a system of electrical currents flow, driven by electric fields generated by fluctuating dynamics within the Earths magnetosphere. These fluctuating dynamics are caused by interactions between the magnetosphere and the solar ... -
Interstellar Dust in the Inner Heliosphere and Impact Detection Capabilities with ESA's Solar Orbiter Spacecraft
(Master thesis; Mastergradsoppgave, 2022-05-31)ESA’s Solar Orbiter spacecraft provides a new opportunity to investigate the inner heliosphere close to sun, by taking measurements with state-of-the-art instruments it will help uncover the mysteries of the Sun. Solar Orbiter is planned for a 7 year mission, reaching as close as 0.28 AU to the sun. Using a process called impact ionization, dust fluxes can be measured during the mission. Some ... -
Polar Mesospheric Winter Echoes - an analysis of selected cases
(Mastergradsoppgave; Master thesis, 2022-05-31)Polar Mesospheric Winter Echoes (PMWE) are strong coherent radar echoes, from the upper mesosphere at 55-85 km that are observed typically from end of August until beginning of May. Some models to explain PMWE formation suggest that they form because of turbulence in the atmosphere. Other models suggest that the PMWEs form like summer polar mesospheric echoes (PMSE) where charged dust particles ... -
Frequency Dependence of Ionospheric Electron Heating Around the Third Double Resonance
(Mastergradsoppgave; Master thesis, 2022-05-31)The partly ionized ionosphere responds differently to high power, high frequency radio waves based on the wave frequency, the wave power, the wave polarization, and the propagation angle relative to the magnetic field. Ionospheric modification experiments are conducted to investigate the responses and their dependencies, setting experimental constraints on the contributions from non-resonant collisional ... -
Disambiguation of range-Doppler radar measurements
(Mastergradsoppgave; Master thesis, 2022-05-31)Observing the Moon by a monostatic synthetic-aperture radar system has the inherent problem that any given combination of range and Doppler shift in a measurement will map to two different regions on the lunar surface. This ambiguity has previously been avoided using an interferometric radar configuration or selective illumination. The objective of this thesis was to write and validate a method for ... -
Design and implementation of an oblique ionosonde receiver. For studies of spatial and temporal ionospheric structures
(Mastergradsoppgave; Master thesis, 2022-05-27)The study of the ionosphere has been of central interest since its discovery in the early 20th century. In later decades there has been an increasing appreciation and need for understanding the spatial and temporal structure of the ionosphere and how the structure is affected by various processes in the atmosphere. An important process in this context is that of atmospheric gravity waves ... -
The influence of mass loss on the dynamics of dust near the Sun
(Mastergradsoppgave; Master thesis, 2021-12-28)The Parker Solar Probe (PSP) mission by NASA and the Solar Orbiter (SolO) mission by ESA are two recently launched missions that measure dust in the inner solar system. The dust is produced by fragmentation of meteoroids, which are large fragments of the asteroids and comets. The dust particles are small enough that their motion is affected by the radiation pressure force from the Sun. Dust fragments ... -
Radar observations of space debris in polar orbits 2018–2021. A study on the evolution of the Microsat-R fragments
(Master thesis; Mastergradsoppgave, 2021-07-02)Orbits are an invaluable resource for the global community. However, space pollution is becoming more pronounced as the accumulation of debris continues. Deliberate collisions are a relevant source contributing to this development. When Microsat-R was destroyed with a missile in 2019, it ejected numerous fragments into orbit. Based on observations made with EISCAT UHF, this thesis will investigate ... -
On Trapped Particle Dynamics in Rotating Frames
(Mastergradsoppgave; Master thesis, 2021-07-01)The rapid rotation of Jupiter and Saturn, combined with internal source of plasma provided by their moons Io and Enceladus respectively, creates a magnetodisk structure of the planetary magnetic field. The magnetodisk looks like a stretched dipole magnetic field in the equatorial region, where centrifugal force is largest. The centrifugal force, originating in the rotating frame, is known to have ... -
A model for IS spectra for magnetized plasma with arbitrary isotropic velocity distributions
(Mastergradsoppgave; Master thesis, 2020-06-27)The plasma line in the incoherent scatter spectrum is known to provide information about the state of the ionosphere. However, it is weak in signal strength and therefore difficult to measure reliably and consistently. When high-energetic electrons (suprathermal electrons) are present in the ionosphere the plasma line echo power is enhanced and detectable by more radars. Recent measurements made by ... -
Design and Implementation of a Software Defined Ionosonde. A contribution to the development of distributed arrays of small instruments
(Master thesis; Mastergradsoppgave, 2020-06-29)In order to make advances in studies of mesoscale ionospheric phenomena, a new type of ionosonde is needed. This ionosonde should be relatively inexpensive and small form factor. It should also be well suited for operation in a network of transmit and receiver sites that are operated cooperatively in order to measure vertical and oblique paths between multiple transmitters and receivers in the ...
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