Fireball Camera Networks

 ¢   Methodology
 Ø  Employ low-cost, sensitive, weather-protected video cameras, generally configured  for all-sky
         monitoring using fisheye lens
 Ø  Digitize video to permit computerized processing
 Ø  Detect fireballs via frame-to-frame comparison
    Ø  Record pixel positions and intensity on a frame-by-frame basis (calibrate viewing geometry using stars and planets). Fireball brightness is measured by
         comparing to camera’s full moon response

¢   Local networks typically consist of 2-4 cameras
 Ø  At least two are required to define track geometry
 Ø  Timing accuracy of tens of milliseconds or better needed for precise track/travel velocity determination

Meteor Physics 

¢   Meteor phenomenon not completely understood – models are hydrodynamics based

¢   Many enigmas exist – a few are listed below   
 Ø  Meteor “electrophonic sound”
    Ø  High altitude luminosity
    Ø  Hypervelocity jets
    Ø  Gross fragmentation at low dynamic pressure
    Ø  “green fireballs”

¢   Better understanding would probably result if electrical actions were considered

Other Interesting Events in the Night Sky - Some Are Controversial

 ¢   Iridium Flares
      An "Iridium flare" is a bright light in the sky that appears for a few seconds (or more) and moves slowly for some distance. The brightest and most frequent
      Iridium flares are caused by intense reflections of the Sun from mirror-like "main mission antennas" on Iridium satellites. There are also predictable, though less
      reliable and not as bright, flares from the satellites' solar panels.   From http://web.austin.utexas.edu/edcannon/iridium.htm
      Additional commentary from the Astronomical Society of South Australia: http://www.assa.org.au/observing/iridium/

¢   “Point Meteors”
     Meteors are supposed to be long streaks of light, but occasionally one comes straight at you and it looks like a point. They are referred to as Point Meteors

¢   Lightning
     Lightning is caused by a discharge of electrical energy that has built up inside a thundercloud. During a thunderstorm, processes involving things such as
     vertical winds and different-sized water droplets cause electrical charges to build up in various parts of the cloud. When these charges become powerful
     enough, they discharge, causing a stroke of lightning. http://earth.rice.edu/MTPE/atmo/atmosphere/topics/lightning/lightning2.html

¢   Ball Lightning
     Ball lightning may be an atmospheric electrical phenomenon, the physical nature of which is still controversial. The term refers to reports of luminous, usually  
     spherical objects which vary from pea-sized to several meters in diameter. It is sometimes associated with thunderstorms, but unlike lightning flashes, which
     last only a fraction of a second, ball lightning reportedly lasts many seconds - http://en.wikipedia.org/wiki/Ball_lightning

¢   UFOs
     Vehicles flown by vertically challenged green people with big eyes and big heads

¢   Sky Flashes