17:47 The Warriors have come through their week from hell with the perfect result as they beat the Dragons 26-10 in the NRL at Mount Smart Stadium.

17:46 The prime minister's talking up the possibility of a free trade deal with India as the Indian president visits New Zealand.

17:45 A large rally's underway in Whangarei to support the victim of a vicious abduction and sexual assault.

16:15 Police have launched an investigation into the 111 emergency phone service, after it failed overnight.

15:26 Civil Aviation Authority investigators are heading to the scene of a fatal helicopter crash in Central Otago.

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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