All‐sky imaging data of 630.0 nm airglow emissions are used to study the seasonal and solar activity dependence medium‐scale traveling ionospheric disturbances (MSTIDs) over Arecibo, Puerto Rico (18.3° N, 66.7° W, 28° N mag lat). MSTIDs typical F‐region signatures at midlatitudes, yet limited statistical results in American sector hindered progress our understanding these dynamical structures. This compiles from 2002 2007 shows for first time that optically‐determined Arecibo present a...

Abstract During the 17 March 2015 geomagnetic storm, citizen scientist observations from Dunedin (45.95°S, 170.32°E), New Zealand, revealed a bright wide red arc known as stable auroral (SAR) evolving into thin white‐mauve arc, Strong Thermal Emission Velocity Enhancement (STEVE). An all‐sky imager at Mount John Observatory (43.99°S, 170.46°E), 200 km north of Dunedin, detected an extremely in 630.0 nm, with peak ∼6 kR, colocated measured assumed height 425 km. Swarm satellite data plasma...

In 1973, the launch of Skylab created a ~50% depletion in daytime ionosphere over N. Atlantic Ocean that lasted for hours. This effect was discovered data being routinely gathered by radio receivers monitoring Total Electron Content (TEC) using Faraday rotation signal from ATS-3 geostationary satellite. “ionospheric hole” H2O and H2 rocket exhaust reacting with ambient O+ F region. reaction is ~2 orders magnitude faster than “normal” between O2....

Ionospheric physics deals with the basic structure and variability of plasma within upper atmospheres Earth planets. Comparative studies foster both exploration synthesis diverse settings. In this paper we examine observations ionospheric profiles on Mars obtained 9–27 March 1999 by radio science experiment onboard Global Surveyor satellite, compare their day‐to‐day same‐day Earth. Using photochemical‐equilibrium arguments applicable to peak electron density layer E‐layer Earth, find...

[1] All-sky imaging systems at Arecibo, Puerto Rico (18.3°N, 66.7°W, +28° mag. lat.), and Mercedes, Argentina (34.6°S, 59.4°W, −24.6° are used to study ionospheric conjugate processes lower midlatitudes. For the first time in American sector simultaneous occurrence both hemispheres of medium-scale traveling disturbances has been observed. The year observations yielded 43 nights (∼40%) with airglow bands. Supporting information from GPS receivers indicate presence vertical total electron...

Abstract An all‐sky imaging system at the McDonald Observatory (30.67°N, 104.02°W, 40° magnetic latitude) showed dramatic ionospheric effects during a moderate geomagnetic storm on 1 June 2013. The auroral zone expanded, leading to observation of stable red (SAR) arc. Airglow depletions associated with equatorial spread F (ESF) were also seen for first time such high latitude. Total electron content measurements from Global Positioning System (GPS) receiver exhibited irregularities typically...

Abstract Since 1987, an all‐sky airglow imaging system has operated from a site at the Millstone Hill/Haystack Observatory in Westford, MA. During ~2.5 solar cycles 1987 to 2014, many studies using images, conjunction with incoherent scatter radar and satellite data, described subauroral, ionospheric disturbances observed during individual geomagnetic storms. The most prominent storm time optical feature subauroral is stable auroral red (SAR) arc. standard use of SAR arc's position locate...

Abstract. In contrast to the polar aurora visible during geomagnetic storms, stable auroral red (SAR) arcs offer a sub-visual manifestation of direct magnetosphere-ionosphere (M-I) coupling at midlatitudes. The SAR arc emission 6300 Å is driven by field-aligned magnetospheric energy transport from ring current/plasmapause locations into ionosphere-thermosphere system. first was observed dawn space age (1956), and typical brightness levels occurrence patterns obtained subsequent decades...

Abstract All‐sky imagers located in Asiago, Italy (45.87 o N, 11.53 E; 40.7 magnetic latitude) and Sutherland, South Africa (32.37 S, 20.81 −40.7 are used to study magnetically conjugate medium scale traveling ionospheric disturbances (MSTIDs). We present initial results from the first year of joint Asiago‐Sutherland data sets July 2016 June 2017. The 630.0‐nm airglow perturbations showing different kinds waves were frequently observed. Some these wave events resemble MSTIDs propagating...

Abstract On September 28, 2017 citizen scientist observations at Alberta, Canada (51°N, 113° W) detected aurora and a thin east‐west purplish arc, known as strong thermal emission velocity enhancement (STEVE) that lasted less than 20 min. All‐sky imagers subauroral latitudes measured stable auroral red (SAR) arcs during the entire night. The imager Bridger, MT (45.3°N, 108.9°W) also STEVE. overlapping geometry allowed to determine height of STEVE was 225–275 km. is brighter in 630.0 nm...

Abstract An all‐sky imager (ASI) records atmospheric emissions from zenith to low on the horizon at all azimuths, a region typically spanning millions of square kilometers. Each pixel (with its unique elevation, azimuth, and emission height) can be mapped along B‐field lines equatorial plane magnetosphere. Auroral subauroral structures boundaries seen in within ionosphere‐thermosphere (I‐T) system thus related source regions. For midlatitude site, this I‐T inner magnetosphere connection...

Abstract During the geomagnetic storm of 1 June 2013, all‐sky imagers located at geomagnetically conjugate locations Millstone Hill, USA (42.6°N, 71.4°W, 50.9° mag lat) and Rothera, Antarctica (67.5°S, 68.1°W, ‐53.2° lat), allowed us to measure a stable auroral red (SAR) arc simultaneously in both hemispheres for first time. The measured one hemisphere was observed very close its location opposite hemisphere. While spatial characteristics, such as equatorward motion latitudinal extent, were...

Abstract Stable auroral red (SAR) arcs offer subvisible evidence for storm time linkages between the inner magnetosphere and midlatitude ionosphere. A SAR arc's defining characteristics are horizon‐to‐horizon east‐west extent, a few degrees of latitude in meridional emission only at oxygen 6300 Å line, minimal brightness changes during night—effects readily provided by steady heat conduction from ring current‐plasmapause interaction region. Here we describe typical arc (brightness ~300...

We describe the introduction of first all‐sky imaging system for low‐light‐level optical observations disturbed ionosphere over mid‐latitude Europe. Using 6300 Å auroral emissions that come from 200–400 km altitude range, we demonstrate sub‐visual patterns spanning European continent can be obtained a single site in Italy. Pilot during 26–27 September 2011 geomagnetic storm show diffuse aurora's low latitude boundary used to find where poleward wall ionospheric trough is located. This...

Abstract Ionospheric storm effects at midlatitudes were analyzed using different ground‐based instruments distributed in Italy during the 13–15 November 2012 geomagnetic storm. These included an all‐sky imager (ASI) Asiago (45.8°N, 11.5°E), a network of dual‐frequeny Global Navigation Satellite Systems receivers (Rete Integrata Nazionale GPS network), and ionosondes Rome (41.8°N, 12.5°E) San Vito (40.6°N, 17.8°E). measurements showed unusual enhancement total electron content (TEC) southern...

Abstract. In March 2014 an all-sky imager (ASI) was installed at the Jicamarca Radio Observatory (11.95∘ S, 76.87∘ W; 0.3∘ S MLAT). We present results of equatorial spread F (ESF) characteristics observed and low latitudes. Optical 6300 7774 Å airglow observations from ASI are compared with other collocated instruments ASIs El Leoncito, Argentina (31.8∘ 69.3∘ 19.8∘ MLAT), Villa de Leyva, Colombia (5.6∘ N, 73.52∘ 16.4∘ N use radar data, in incoherent coherent modes, to obtain plasma...

Abstract Stable auroral red (SAR) arcs provide opportunities to study inner magnetosphere‐ionosphere coupling at midlatitudes. An imaging system a single‐site obtains evidence of seasonal variations in SAR arc brightness and occurrence rates using events widely separated time, as observed during different geomagnetic storms. The first two all‐sky imagers conjugate points described effects the same time for storm (Martinis, Mendillo, et al., 2019, https://doi.org/10.1029/2018JA026018 ). Here...

Abstract We explore the concept of using an all‐sky imager (ASI) in one hemisphere to provide nowcasting ionospheric perturbations opposite hemisphere. The specific example deals with low‐latitude plasma instabilities known as equatorial spread F (ESF) that largely depend on geomagnetic field controlled electrodynamics. ASI observations 630.0 nm airglow from ~300 km exhibit regions low emission (“airglow depletions”) correlate highly ESF patterns radio wave disruptions, for example, GPS...

Abstract The lunar surface is constantly bombarded by the solar wind, photons, and meteoroids, which can liberate Na atoms from regolith. These are subsequently accelerated photon pressure to form a long comet‐like tail opposite sun. Near new moon, these encounter Earth's gravity “focused” into beam of enhanced density. This appears as ∼3° diameter Sodium Moon Spot (SMS). Data all sky imager at El Leoncito Observatory have been analyzed for changes in SMS shape brightness. New geometry‐based...

630.0 nm all-sky imaging data are used to detect airglow depletions associated with equatorial spread F. Pairs of imagers located at geomagnetically conjugate locations in the American sector low and mid-latitudes provide information on occurrence rate zonal motion depletions. Airglow seen extending magnetic latitudes as high 25°. An asymmetric extension is observed structures northern hemisphere reaching higher latitudes. By tracking depletions, plasma drifts thermosphere can be inferred...

Using a new all-sky-imaging system, M Mendillo, C Barbieri, J Baumgardner, Wroten, G Cremonese and Umbriaco observed two distinctive types of aurora over London western Europe on the night 26–27 September 2011, including first ground-based image stable auroral red arc Europe.