10:13 Police looking into a Head Hunters gang threat to Vincent Skeen who was found not guilty of 17yr old Luke Tipene's murder last week.

10:09 Winds up to 140km/h are expected to batter Wellington, Wairarapa and the Marlborough Sounds until this afternoon. Many warnings are in place.

08:53 Cake and crocodiles will be part of the celebrations at Australia Zoo today as Bindi Irwin celebrates her 18th birthday.

08:41 A new tertiary union survey reveals NZ university staff are feeling pressured to exaggerate student achievement, to meet government targets.

08:39 Ali Sonboly, the German-Iranian 18-yr old who killed nine in Munich, was a deranged lone gunman allegedly obsessed with mass killings.

Fri, 13 Apr 2012

VIDEO: Why don't those stars move?

Stars in the sky will typically appear to rise and set as the Earth turns. If you look closely at the above time-lapse movie, however, there are points of light that appear stationary. These objects are not stars but human-launched robotic spacecraft that remain fixed high above the Earth's equator. Called geostationary satellites, they don't fall down because they do orbit the Earth -- they just orbit at exactly the same speed that the Earth rotates. The orbital distance where this is possible is much farther than the International Space Station but much closer than the Moon. The video was taken from one of the highest revolving restaurants in the world located on the Mittelallalin in the Swiss Alps. An even closer inspection will show that the geostationary satellites flash with glints of reflected sunlight. The satellites also all appear on a single line - actually the projection of the Earth's equator onto the sky.

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