Streamers are the whispy electronic filaments that feel their way towards the ground in the fraction of a second before a lightning strike. They differ from the main strike in that they do not significantly increase the gas temperature.
They are also seen in nature as sprites, giant electronic discharges that sit 100 kilometres or so above active thunderstorms.
A number of groups have captured ordinary 2D images of streamers, which have a complex, fragmented shape. But nobody has determined their 3D structure.
Now Sanders Nijdam and pals at Eindhoven University of Technology in the Netherlands have captured the first 3D image of a streamer.
Their set up is pretty straigthforward. A stereo camera photographing a discharge in air. They then digitised the images to create a model of the streamer.
That’s handy because streamers may be useful in various applications such as ozone generation, bio fuel processing and plasma assisted combustion, say the group.
Ref: arxiv.org/abs/0802.3639: Stereo-photography of Point-Plane Streamers in Air