Sökning: "near-Earth objects"

Hittade 2 avhandlingar innehållade orden near-Earth objects.

1. 1. From meteors to space safety : dynamical models and radar measurements of space objects

   Författare :Daniel Kastinen; Johan Kero; Asta Pellinen-Wannberg; Mats Holmström; Detlef Koschny; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Meteors; meteor shower; atmosphere; meteoroids; meteoroid stream; small-body dynamics; solar system; comets; asteroids; near-Earth objects; space safety; space debris; radar; MU; EISCAT;

   Sammanfattning : Every day the Earth's atmosphere is bombarded by 10-200 metric tons of dust-sized particles and larger pieces of material from space called meteoroids. Dust and meteoroids come from parent bodies such as comets and asteroids, which are remnants from the formation of the solar system. LÄS MER

3. 2. Secondary Electromagnetic Radiation Generated by HF Pumping of the Ionosphere

   Författare :Lars Norin; Bo Thidé; Savely M. Grach; Bengt Gustafsson; James W. LaBelle; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; space physics; ionospheric modification experiments; plasma turbulence; stimulated electromagnetic emission; ionospheric irregularities; radio waves; parametric processes; thermal parametric instability; transient dynamics; wave-wave interactions; Physics; Fysik;

   Sammanfattning : Electromagnetic waves can be used to transmit information over long distances and are therefore often employed for communication purposes. The electromagnetic waves are reflected off material objects on their paths and interact with the medium through which they propagate. LÄS MER