A review of unusual VLF bursty-patches observed in Northern Finland for Earth, Planets and Space

A review of unusual VLF bursty-patches observed in Northern Finland for Earth, Planets and Space

https://earth-planets-space.springeropen.com/articles/10.1186/s40623-021-01516-y?fbclid=IwAR0p-aSifMwAANdD9GRMdyAhTS1KHpqB67it33udPzCnwl7QogzC6TvDhTA

”Thankfully, the data from the VLF receiver at Kannuslehto [KAN, MLAT = 64.4, L ~ 5.5] in Northern Finland, has been analyzed with a sferics filter allowing for clearer observations at frequencies above the local 0.5 fce eq at the L-shells of KAN (0.5 fce eq = 2.7 kHz). KAN not only observed emissions similar to the bursty-patches as described by Shiokawa et al. (2014), but also detected multiple other types at unusually higher frequencies, above the local equatorial gyrofrequency (fce eq. = 5.4 kHz). Manninen et al. (2016) made a first report of these type of unusually high frequency natural VLF emissions without focusing on their different characteristics but grouping them together as RREs (i.e., recently revealed emissions). They showed that these emissions are a dayside phenomenon, peaking close to local noon. They were detected on 78% of all campaign days between 2006 and 2016, and seem to be mostly hiss-like in nature. While the mechanisms behind their generation and propagation remain mostly unknown, they could be generated due to self-oscillations in the magnetospheric maser and should originate at L-shells lower than the position of KAN (Manninen et al. 2017).

Even though these unusual high frequency emissions tend to look like hiss bursts, on closer inspection they show a wide variety of spectral shapes. In some cases, they are shaped like bullets with sudden stops or show wing-like features, while in other cases, we note gradual frequency increase or showing multiple periodic features (Manninen et al. 2016, 2017). More recently, Manninen et al. (2021) described these type of emissions as high-frequency VLF patches or VLF ‘birds’ and focused on their relationship to temporal and spatial details of wave–particle interactions. They noticed that these waves were only observed at times of no or weak space weather conditions. They concluded that VLF-patches could indirectly indicate a local enhancement of electron fluxes and could be generated even if they were not being detected on the ground. While we understand a bit more on these waves, the reasons behind this variety of shapes or periodicity mechanisms are still unknown”

Sillä tavalla 😃

Hyvä me, hyvä Suomi 😃

Tiedä vaikka olisivat todistamassa meikäläisen näkemyksen oikeaksi siitä että osa avaruudessa laajenevasta Auringosta peräisin olevasta laajenevasta pimeästä työntävästä voimasta voi laajentua havaittavissa olevaksi energiaksi / työntäväksi voimaksi kun kohtaa vastapalloon laajenevan Maapallon keskustasta peräisin olevaa laajenevaa työntävää voimaa jne 😃

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When the Solar Wind Slams Into Earth’s Magnetosphere, a Surprising Stillness Ensues

”When the solar wind hits the magnetosphere, waves of energy are transferred along the boundary between the two. Scientists thought the waves should ripple in the direction of the solar wind, but the new study, published recently in Nature Communications, reveals some waves do just the opposite.”

Tää on erittäin mielenkiintoinen uutinen 😃

Näinköhän avaruudessa laajenevasta Auringosta peräisin olevat laajenevat energia-aallot saavat avaruudessa laajenevan Maapallon keskustasta peräisin olevat laajenevan pimeän työntävän voiman aallot laajenemaan havaittavissa oleviksi laajeneviksi energia-aalloiksi 🤔

Silloinhan tuossa olisi kyse kaikessa yksinkertaisuudessaan siitä että aallot jotka olivat jo liikkeessä pois päin Maapallosta, työntyvät vain esiin rekisteröitävissä oleviksi aalloiksi 😃

😃