08:50 The family of promising league player Luke Tipene, slain by another teenager at a party, is devastated they'll have to face another trial.

08:48 Mixed US economic messages - the unemployment rate's fallen to 5.1% but the economy only pumped out a modest 173,000 new jobs last month.

08:42 There have been clashes in Budapest after far-right extremists threw two firecrackers towards migrants, sparking an angry response.

08:40 Hungary has now announced it will now help thousands of mostly Syrian refugees get to Austria by taking them to the border by bus.

07:05 A 65 year old man has undergone emergency surgery in Australia after a shark attack on the mid-north coast of New South Wales.

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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