Sporadic meteor

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In astronomy, sporadic meteors are those falling stars or fireballs that cannot be assigned to a meteor shower.

About 1 to 2 sporadic meteors can be observed per hour at a certain location, almost regardless of the season. They draw their traces of light on the starry sky in all directions and therefore almost follow a random distribution .

Origin and Fall Rates

The mostly about mm-large particles can be regarded as leftovers from the formation of the solar system. You either stayed

  • in the formation of planets or planetoids left
  • are fragments of collisions in the early days of the solar system
  • or decay products of comets .

Sporadic meteors were part of the interplanetary dust before they burned up and originate mainly from the asteroid belt between the orbits of Mars and Jupiter . There, myriads of small dust grains and rock particles from mm to cm in size move on various elliptical orbits around the sun. A few percent of these particles run on trajectories that cross the earth's orbit , so that they sometimes penetrate into the earth's atmosphere . They can also come from further outside if they are drifting towards the inner solar system due to orbital disturbances or tidal forces.

The vast majority of these particles already burn up at an altitude of around 100 km when they enter the high atmosphere . Only larger pieces can survive the tremendous frictional heat and fall onto the surface of the earth as meteorites .

Sporadic meteors can always appear, but their frequency varies over the course of the day . From midnight , especially in the morning sky is the case rate significantly higher because of the then location of the observer is on the front of the earth around the sun. As a result, the Earth-related speed of the meteors is higher, while they burn up the slowest in the evening.

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