Publications by authors named "Herbert Gunell"
Plasma flows with enhanced dynamic pressure, known as magnetosheath jets, are often found downstream of collisionless shocks. As they propagate through the magnetosheath, they interact with the surrounding plasma, shaping its properties, and potentially becoming geoeffective upon reaching the magnetopause. In recent years (since 2016), new research has produced vital results that have significantly enhanced our understanding on many aspects of jets.
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- The Comet Interceptor mission aims to explore a long-period comet or an interstellar object entering our Solar System, with a focus on its surface composition, shape, and the composition of its gas and dust.
- Proposed to the European Space Agency in 2018 and approved in June 2022, it is set to launch in 2029 alongside the Ariel mission, utilizing a low-cost approach that allows it to wait for a suitable target comet.
- The mission will feature a main probe and two sub-probes (B1 from JAXA and B2), providing simultaneous, detailed 3D information about the comet and its interaction with the solar wind, making it unique compared to previous missions.
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- Magnetosheath jets are plasma entities found around Earth that exert higher dynamic pressure than their surroundings and contribute to energy transfer in the magnetosheath.
- These jets create waves that affect the magnetopause, leading to noticeable phenomena like throat auroras and detectable magnetic signatures on the ground.
- Research from the MAVEN spacecraft has shown that similar jets also exist in Mars' magnetosheath, indicating their presence can influence both Earth and Mars, despite the differences in their respective environments.
The environment of a comet is a fascinating and unique laboratory to study plasma processes and the formation of structures such as shocks and discontinuities from electron scales to ion scales and above. The European Space Agency's Rosetta mission collected data for more than two years, from the rendezvous with comet 67P/Churyumov-Gerasimenko in August 2014 until the final touch-down of the spacecraft end of September 2016. This escort phase spanned a large arc of the comet's orbit around the Sun, including its perihelion and corresponding to heliocentric distances between 3.
View Article and Find Full Text PDFThe Rosetta mission shall accompany comet 67P/Churyumov-Gerasimenko from a heliocentric distance of >3.6 astronomical units through perihelion passage at 1.25 astronomical units, spanning low and maximum activity levels.
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