![]() These waves play a key role in middle-atmosphere dynamics, but also modulate the luminosity of elves and possible sprites. Special DSLR cameras with their IR cut filters removed also can capture sprites, and in addition, convectively-generated gravity waves in the airglow layer near the mesopause. These were captured by multiple low-light Watec 902H U cameras, as well as detailed color images using a Nikon D4S. This same night, a modest MCS in northeastern NM also produced a number of highly photogenic sprites. This provides one of the most complete descriptions of sprite phenomenology to date. A detailed analysis of the entire discharge process employs the images, NMQ gridded radar reflectivity data, the LMA VHF sources, NLDN and CMCN data, and VLF/ ELF retrievals of time dependent charge moment changes. Concurrently, the sprite parent +CG (SP+CG) was also imaged at 10000 ips by a Phantom deployed in a mobile van as part of the NSF-funded UPLIGHTS effort. A classic “jellyfish” sprite was captured by an intensified high-speed (10000 ips) Phantom camera in Ft. Around 0800 Z on 19 July 2014 a relatively small MCS moved through the Rapid City, SD area and its 3-D Lightning Mapping Array (LMA). We focus on several dates during June - August 2014, in which excellent illustrations of the capabilities of these technologies were obtained. During the 2014 summer campaign for the DARPA Physical Origins of Coupling to the Upper Atmosphere from Lightning (PhOCAL) project, various sensor systems were deployed. Rapid advances in sensor and camera technology during the past decade have created many opportunities to extend our understanding of TLEs and their parent lightning. Sprites are induced by exceptionally powerful CG lightning discharges, which themselves have been investigated for over a century using both still and video imagery. Since then a wide variety of cameras and optical sensors have played key roles in understanding the morphology of TLEs and providing objective measurements to validate theories as to their formation. Winckler serendipitously captured by the first image of a sprite, the most common class of lightning-related transient luminous events, above a Minnesota thunderstorm. Elves were discovered in 1992 by a low-light video camera on the Space Shuttle.A low-light camera system being ground tested for a rocket experiment in July, 1989 by Prof. Scientists believe elves result when an energetic electromagnetic pulse extends up into the ionosphere. They last less than a thousandth of a second, and occur above areas of active cloud to ground lightning. Blue jets last a fraction of a second and have been witnessed by pilots.Įlves are rapidly expanding disk-shaped regions of glowing that can be up to 300 miles across. They extend up in narrow cones fanning out and disappearing at heights of 25-35 miles. They are rarely seen with the human eye, so they are most often imaged with highly sensitive cameras.īlue jets emerge from the top of the thundercloud, but are not directly associated with cloud-to-ground lighting. Because sprites are not very bright, they can only be seen at night. Sprites are mostly red and usually last no more than a few seconds, and their shapes are described as resembling jellyfish, carrots, or columns. They can extend up to 60 miles from the cloud top. They usually happen at the same time as powerful positive CG lightning strokes. Red Sprites can appear directly above an active thunderstorm as a large but weak flash. The most common TLE's include red sprites, blue jets, and elves. Large thunderstorms are capable of producing other kinds of electrical phenomena called transient luminous events (TLE's).
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