On the magnetospheric ULF wave counterpart of substorm onset

One near‐ubiquitous signature of substorms observed on the ground is the azimuthal structuring of the onset auroral arc in the minutes prior to onset. Termed auroral beads, these optical signatures correspond to concurrent exponential increases in ground ultralow frequency (ULF) wave power and are likely the result of a plasma instability in the magnetosphere. Here, we present a case study showing the development of auroral beads from a Time History of Events and Macroscale Interactions during Substorms (THEMIS) all‐sky camera with near simultaneous exponential increases in auroral brightness, ionospheric and conjugate magnetotail ULF wave power, evidencing their intrinsic link. We further present a survey of magnetic field fluctuations in the magnetotail around substorm onset. We find remarkably similar superposed epoch analyses of ULF power around substorm onset from space and conjugate ionospheric observations. Examining periods of exponential wave growth, we find the ground‐ and space‐based observations to be consistent, with average growth rates of ∼0.01 s−1, lasting for ∼4 min. Cross‐correlation suggests that the space‐based observations lead those on the ground by approximately 1–1.5 min. Meanwhile, spacecraft located premidnight and ∼10 RE downtail are more likely to observe enhanced wave power. These combined observations lead us to conclude that there is a magnetospheric counterpart of auroral beads and exponentially increasing ground ULF wave power. This is likely the result of the linear phase of a magnetospheric instability, active in the magnetotail for several minutes prior to auroral breakup

Design and development of a miniaturised flow-through measuring device for the in vivo monitoring of glucose and lactate

The aim of this thesis was to develop a (portable) miniaturized device for long-term continuous real time in vivo monitoring of analytes, such as glucose and lactate. Both glucose and lactate are markers for energy metabolism, as glucose is the major energy substrate for the body and lactate is released during oxygen deficiency. Glucose and lactate can be monitored in a wide variety of settings, such as during athletic performance and pathological situations like brain trauma, diabetes and heart failure. Because an interruption in the energy supply to organs, such as the brain and the heart, can quickly lead to lifethreatening situations, the need and potential of these devices have been long recognized in clinical diagnostics. By means of real time continuous in vivo monitoring rapid clinical intervention can be established and, as a consequence, may prevent further damage. Additionally, for large patient groups, such as patients suffering from diabetes mellitus, the quality of life will be improved when frequent finger pricking to control their blood glucose level can be significantly reduced.

A Small Satellite Constellation for Monitoring of the Aurora

As part of the European Space Agency\u27s D3S (Distributed Space Weather Sensor System), a small satellite constellation is currently being designed by OHB Sweden which will observe space weather impacts in Earth\u27s vicinity by monitoring of the auroral oval. The primary objective of the Aurora mission is to observe the Aurora Borealis and Australis continuously and as complete as possible. The auroral emissions are the result of interactions of the Solar Wind and Coronal Mass Ejections with the Earth which drive the location and strength of electron precipitation on the ionosphere. Such observations will thereby allow the identification, characterization and nowcasting of geomagnetic storms and sub-storms. Observation of the auroral emissions is expected to enable improved and new services relevant for critical infrastructures such as communication, satellite navigation, satellite operation, aviation, transport, power network operation, and resource utilization. The core instruments of the Aurora mission are the optical and far UV wide-field imagers. Furthermore, a radiation monitor and a magnetometer are baselined as a secondary payload to monitor magnetic field dynamics and the radiation environment. The availability of additional resources for other payloads relevant for D3S is under investigation. To minimize the number of satellites, while ensuring continuous and guaranteed coverage of the auroral oval, a constellation of four satellites in MEO orbit is envisaged. Such orbit however poses significant challenges for small satellites in terms of accessibility, sustainability, and radiation dose. The heritage microsatellite platform from OHB Sweden, InnoSat (designed for LEO), will thus undergo several upgrades in terms of maneuverability, shielding, communication, and reliability. Of particular importance is the low latency requirement which may favor an Inter-Satellite Link. In a first step ESA is implementing a demonstrator mission that shall be launched in 2027 with the aim of optimizing the performance and preparing the operational satellite constellation considered for implementation in a second step. We will report about the status of the satellite design and the mission architecture

Hot Vents Beneath an Icy Ocean: The Aurora Vent Field, Gakkel Ridge, Revealed

Evidence of hydrothermal venting on the ultra-slow spreading Gakkel Ridge in the Central Arctic Ocean has been available since 2001, with first visual evidence of black smokers on the Aurora Vent Field obtained in 2014. But it was not until 2021 that the first ever remotely operated vehicle (ROV) dives to hydrothermal vents under permanent ice cover in the Arctic were conducted, enabling the collection of vent fluids, rocks, microbes, and fauna. In this paper, we present the methods employed for deep-sea ROV operations under drifting ice. We also provide the first description of the Aurora Vent Field, which includes three actively venting black smokers and diffuse flow on the Aurora mound at ~3,888 m depth on the southern part of the Gakkel Ridge (82.5°N). The biological communities are dominated by a new species of cocculinid limpet, two small gastropods, and a melitid amphipod. The ongoing analyses of Aurora Vent Field samples will contribute to positioning the Gakkel Ridge hydrothermal vents in the global biogeographic puzzle of hydrothermal vents

New Science in Plain Sight:Citizen Scientists Lead to Discovery of Optical Structure in the Upper Atmosphere

A glowing ribbon of purple light running east-west in the night sky has recently been observed by citizen scientists. This narrow, subauroral, visible structure, distinct from the traditional auroral oval, was largely undocumented in the scientific literature and little was known about its formation. Amateur photo sequences showed colors distinctly different from common types of aurora and occasionally indicated magnetic field–aligned substructures. Observations from the Swarm satellite as it crossed the arc have revealed an unusual level of electron temperature enhancement and density depletion, along with a strong westward ion flow, indicating that a pronounced subauroral ion drift (SAID) is associated with this structure. These early results suggest the arc is an optical manifestation of SAID, presenting new opportunities for investigation of the dynamic SAID signatures from the ground. On the basis of the measured ion properties and original citizen science name, we propose to identify this arc as a Strong Thermal Emission Velocity Enhancement (STEVE)

Magnetic shell enhancements during magnetic disturbances

Magnetic shell enhancements during magnetic field disturbances from Langmuir probe observations of electron density on Ariel I satellit