Rare observations of sprites and gravity waves supporting D, E, F-regions ionospheric coupling

We report rare simultaneous observations of columniform sprites and associated gravity waves (GWs) using the Transient Luminous Events (TLEs) camera and All-sky imager at Prayagraj (25.5° N, 81.9° E, geomag. lat. ~ 16.5° N), India. On 30 May 2014, a Mesoscale Convective System generated a group of sprites over the north horizon that reached the upper mesosphere. Just before this event, GWs (period ~ 14 min) were seen in OH broadband airglow (emission peak ~ 87 km) imaging that propagated in the direction of the sprite occurrence and dissipated in the background atmosphere thereby generating turbulence. About 9–14 min after the sprite event, another set of GWs (period ~ 11 min) was observed in OH imaging that arrived from the direction of the TLEs. At this site, we also record Very Low Frequency navigational transmitter signal JJI (22.2 kHz) from Japan. The amplitude of the JJI signal showed the presence of GWs with ~ 12.2 min periodicities and ~ 18 min period. The GWs of similar features were observed in the ionospheric Total Electron Content variations recorded at a nearby GPS site. The results presented here are important to understand the physical coupling of the troposphere with the lower and upper ionosphere through GWs.

Design and construction of hardware and software for autonomous observations of Transient Luminous Events

Transient luminous events (TLE) are phenomena which are currently on the rise in terms of sightings. However, there is no widespread uniform method of their observation and subsequent image processing. Therefore, our project focuses on the design and construction of hardware that can record TLE. It consists of a low gain, colour, CMOS camera with a bright, wide lens connected to a small, power-efficient single board computer. The project also includes writing software to control the hardware. The software decides whether to capture or not and at what orientation there is the biggest chance to capture a TLE. The software can process and classify the created photos based on deep neural networks. As a final product, we have developed the whole apparatus from a hardware and software point of view and installed it at the Astronomical Observatory at Kolonica Saddle in Slovakia, Central Europe. The plan for the future is to make similar apparatuses to spread the observation network.

Resolving Elve, Halo and Sprite Halo Images at 10,000 Fps in the Taiwan 2020 Campaign

After almost thirty years’ efforts on studying transient luminous events (TLEs), ground-based observation has confirmed the TLE family, including elves, halos, sprites, and blue jets, etc. The typical elve has the shortest emission time (<1 ms) in comparison with other TLEs. The second shortest is the halo emission. Although elves and halos are supposed to be more frequent than sprites, ground campaigns still have less probability of recording their images due to their fleeting and short emission. Additionally, the submillisecond imaging of elves, halos, and sprite halos helps us resolve their electro-optic dynamics and morphological features, but few have been reported in the literature. Our study presents the 10,000 fps imaging frames on elves, halos and sprite halos, compares their similarity and disparity, and analyzes their parent lightning properties with associated VLF and ELF data.

Comprehensive Analysis of a Coast Thunderstorm That Produced a Sprite over the Bohai Sea

Sprites are transient luminous events (TLEs) that occur over thunderstorm clouds that represent the direct coupling relationship between the troposphere and the upper atmosphere. We report the evolution of a mesoscale convective system (MCS) that produced only one sprite event, and the characteristics of this thunderstorm and the related lightning activity are analyzed in detail. The results show that the parent flash of the sprite was positive cloud-to-ground lightning (+CG) with a single return stroke, which was located in the trailing stratiform region of the MCS with a radar reflectivity of 25 to 35 dBZ. The absolute value of the negative CG (−CG) peak current for half an hour before and after the occurrence of the sprite was less than 50 kA, which was not enough to produce the sprite. Sprites tend to be produced early in the maturity-to-dissipation stage of the MCS, with an increasing percentage of +CG to total CG (POP), indicating that the sprite production was the attenuation of the thunderstorm and the area of the stratiform region.

Transient Luminous Events, into the Stratosphere and the Mesosphere, observed during violent thunderstorms lightning, are explained thanks to laboratory jets of photons in air, occuring during emission of Gravitational Quanta

: A Gravitational field emitter, as we patented in 2006, is composed of an “active” material squeezed between two metallic electrodes. The active material is superconducting, with conductive or insulating grains added inside, to get local electric fields during brief electric discharges made into that emitter. Along such a discharge, the emitter propels itself, by anisotropic re-emission of interacting Gravitational Quanta. These emitted quanta accelerate distant matter particles placed along their trajectory. With early YBCO superconducting material emitters, cooled down by liquid nitrogen, we observed systematically a bright emission of light into the bath. This light emission is caused by nitrogen molecules’ ionization by gravitational quanta push. In 2012, the partial superconducting behavior of natural Graphite, at room temperature, was discovered, so we built new emitters from Graphite. These shown the same propelling effect as the early ones made of YBCO, with a lower performance. Here we record and discuss light emission in the form of jets of photons, in air, at room temperature, and pressure, during strong electric discharges into Graphite based emitters. These results enhance the confirmation of predictions from our theoretical Quantum model of Inertia and Gravitation. They explain also the enigmatic Transient Luminous Events observed in the atmosphere over thunderstorms clouds.

La verdad es hija del tiempo

Las descargas eléctricas atmosféricas que se generan entre las nubes y la ionosfera son fenómenos electromagnéticos que se vienen estudiando sistemáticamente a nivel mundial hace muy poco tiempo, cerca de 30 años. Su interés radica en las radiaciones de muy alta frecuencia (rayos gamma) que son muy diferentes a los rayos que hasta ahora se han estudiado en el rango de las radiofrecuencias. En este artículo se presentan los fenómenos denominados destellos de rayos gamma terrestres (Terrestrial Gamma-ray Flash, TGF) y eventos luminosos terrestres (transient luminous events, TLE), y se analiza el papel de los estudios que lleva a cabo en Colombia el grupo PAAS-UN y los beneficios que esta rigurosa y sistemática investigación representan para el futuro del conocimiento científico de los rayos en el país.

Simulations of electric field at the initiation altitudes of sprites and halos generated by the thundercloud charge structure and lightning channels of causative return strokes

&lt;p&gt;&lt;span&gt;Sprites and halos are transient luminous events occurring above thunderclouds. They can be observed simultaneously or they can also appear individually. Circumstances leading to initiation of these events are still not completely understood. In order to clarify the role of lightning channels of causative lightning return strokes and the corresponding thundercloud charge structure, we have developed a new model of electric field amplitudes at halo/sprite altitudes. It consists of electrostatic and inductive components of the electromagnetic field generated by the lightning channel in free space at a height of 15 km. Above this altitude we solve Maxwell&amp;#8217;s equations self-consistently including the nonlinear effects of heating and ionization/attachment of the electrons. At the same time, we investigate the role of a development of the thundercloud charge structure and related induced charges above the thundercloud. We show how these charges lead to the different distributions of the electric field at the initiation heights of the halos and sprites. We adjust free parameters of the model using observations of halos and sprites at the Nydek TLE observatory and using measurements of luminosity curves of the corresponding return strokes measured by an array of fast photometers. The latter measurements are also used to set the boundary conditions of the model.&lt;/span&gt;&lt;/p&gt;

ASIM TGFs with accompanying elves

&lt;p&gt;&lt;span&gt;The Atmospheric Space Interactions Monitor (ASIM) was launched in 2018, and has since then observed Terrestrial Gamma-ray Flashes (TGFs) and Transient Luminous Events (TLEs). ASIM consists of the Modular X- and Gamma-ray Sensor (MXGS) and the Modular Multispectral Imaging Array (MMIA). Using data from both MXGS and MMIA, we investigate observations of TGFs (detected by MXGS) with accompanying elves (detected by MMIA). We study the optical signatures of the elves detected by a photometer of MMIA operating in the 180-230 nm band. Lightning sferics associated with these events have been detected by WWLLN and GLD360. Several TGFs have associated lightning sferics outside the field of view of MMIA, but due to the expanding rings of the elves we can still observe optical signatures from accompanying elves. Using GLD360 data we also study properties of the lightning strokes. &lt;/span&gt;&lt;/p&gt;

БЫСТРЫЕ И ОЧЕНЬ ЭНЕРГИЧНЫЕ. ТРАНЗИЕНТНЫЕ ЭНЕРГИЧНЫЕ ЯВЛЕНИЯ В АТМОСФЕРЕ И В БЛИЖНЕМ КОСМОСЕ, "Земля и Вселенная"

Транзиентными, то есть быстропреходящими, энергичными явлениями в контексте данной статьи называются земные гамма-всплески (Terrestrial Gamma Flashes – TGF), некоторые типы так называемых «транзиентных световых явлений» (Transient Luminous Events – TLE), «быстрые грозовые земные возрастания» (Fast Thunderstorm Ground Enhancements – FTGE). Они появляются как в нижних слоях атмосферы, так и верхней ее области, вплоть до мезосферных (около десятков км) высот в виде кратковременных потоков электронов, позитронов, гамма-квантов и нейтронов, а также всплесков оптического излучения от ультрафиолетового до инфракрасного. Одна из вероятных моделей их объяснения использует как ключевой элемент генерацию лавин субрелятивистских и релятивистских электронов, природа которой может быть связана с быстрыми изменениями атмосферных электрических полей во время проявлений грозовых эффектов (это так называемая модель «снизу-вверх»). Но можно предположить, что электроны меньших энергий могут высыпаться из радиационных поясов Земли в атмосферу (эта модель, соответственно, называется «сверху-вниз»). Именно лавины электронов, проникающие в атмосферу снизу, вкупе с пучками электронов сверху, могут быть ответственны за весь комплекс явлений со значительным выделением энергии и в нижней, и в верхней атмосфере. Не исключено, что все рассматриваемые транзиентные энергичные явления развиваются на примерно одинаковой временной шкале. Предполагается, что аналогичным механизмом можно объяснить и появление потоков транзиентных лавин гамма-квантов в области под грозовыми облаками (феномен FTGE). Ниже излагаем экспериментальные аргументы, подтверждающие предложенные модели, и обсуждаем ряд нерешенных проблем и направления дальнейших целевых экспериментальных исследований в этой области физики экстремальной атмосферы.