Meteor Trail

meteor trail

[′mēd·ē·ər ‚trāl]
(geophysics)

Meteor Trail

 

the train remaining in the atmosphere after the passage of a meteor. There are two types of meteor trails: dust trails and gas, or ionized, trails. Dust trails are formed only by bright bolides at heights of 25–80 km as a result of the condensation of vapors of meteoric material in the head and train of the bolide and the solidification of droplets of molten material blown off the meteor’s surface. At twilight, the luminosity of dust trails is the result of the scattering of sunlight by minute particles, measuring less than 10 ~4 cm in diameter. Dust trails are visible for periods of up to several hours. The luminosity of ionized trails results from recombination processes; the spectra of these trails show lines of Mg, Na, Ca, Fe, and other elements. Ionized trails are formed by all meteors, but only those of bright meteors can be observed by the naked eye. They are visible for periods ranging from fractions of a second to several minutes. Because radio waves are reflected by ionized trails, such trails can be observed by radar.

Initially, the meteor trail is straight and thin; however, wind and diffusion soon cause it to curve and broaden. Optical and radar observations of meteor trails are one of the principal methods of studying the circulation and turbulence of the earth’s atmosphere at heights of 80–110 km.

V. N. LEBEDINETS

References in periodicals archive ?
FOCUS Your camera might be able to snap a meteor trail
There are six steps in the sweep, each illuminating a different portion of the meteor trail.
That bit of matter makes a meteor trail, glowing brightly for a moment, perhaps to the accompaniment of expressions of delight by onlookers below.
Vibrating at 1/20th of a second one camera produced like fluctuations in a meteor trail.
If we assume that the meteor first became visible at a height of 110km we find that the distance to the positions on the ground under the start and end points of the trajectory are 56 and 33km respectively, the length of the meteor trail is 51km and the end height is 70km.
became the first to send a spoken message via meteor trail.
Crossing the tail of Halley's Comet," he said "was a corkscrew meteor trail, about 1[degrees] long, with no fewer than two dozen twists in it
On December 7th people puzzled over what seemed to be a meteor trail striking a lamppost.
He realised that time spent recording the path of each meteor trail could be drastically reduced if, rather than drawing a line on a star chart, the observer committed to memory the designations of all of the brightest 3,000 naked-eye stars and recorded the path simply by naming naked-eye stars close to its start and end points in a notebook.
This large number of reception paths reduces meteor trail orientation and polarisation effects, and gives a higher count-rate than a single transmitter/ receiver path, as might be used in standard forward-scatter observations.
Many of its shooting stars coursed across the heavens, and at one magical moment two meteor trails actually crossed.
We did see some meteor trails but didn't catch them on camera.