Meteorites are rocks that are from outer space that hits the surface of the earth. It is seen as a bright glowing body as it enters the earth's protective atmosphere; these are all originated outside the earth. Where exactly is up for many interesting scientific discussions.
Whenever it hits the earth it a lot of material is spewed out and this is called ejecta. A lot of dust and fragment is ejected into the air. This can release a cloud of debris and cause obstruction of vision and interfere with breathing.
An impact crater is a circular hole formed when a meteorite hits the surface of the earth. Typically when an object moving at a very high speed.
