kuna habari kuwa kuna satellite iliyozeeka ya Marekani ambayo inatarajiwa kuanguka kurudi huku duniani kwa mujibu wa NASA. wanasema saizi yake ni kama basi. ambapo inategemewa itaweza kuunguka wakati ikiingia kwenye anga la dunia na baadhi ya vipande vyake vitaanguka ingawa haitegemewi kudhuru watu. naomba kueleweshwa, ni kwa nini wao(NASA) wanategemea kuwa itaungua. swali lingine, kwa kuwa huko kwenye anga za juu huwa wanasema kuwa hakuna gravitational force, hivyo vitu huwa vinaelea tu kwenye anga bila kuanguka kuja huku chini, sasa kwa nini satellite hiyo isibaki huko huko juu? ni kitu gani kinaivuta kurudi huku duniani?
In the end, all human-made satellites will
fall back to Earth, since objects eventually
lose velocity and are overcome by the
Earths gravity. It may take a very long time
for this to happen, however, because
satellites are so high in space. Satellites near
the Earth in low- Earth orbit may take 10, 20,
or 100 years to fall back to Earth. Satellites
higher up in highly-elliptical or geostationary
orbits may take hundreds, thousands, or
even million of years to fall back to Earth.
Objects falling back to Earth will burn up in
the atmosphere due to the friction caused by
the Earths atmosphere.