21:19 Up to 30 people were in a hotel hit by an avalanche in Italy and many are believed dead.

20:39 Kiwi Antarctic researchers are set to raise a celebratory lamington or two tomorrow to toast 60 years since Scott Base opened.

15:55 Injury has ruled out Bangladesh captain Mushfiqur Rahim and opener Imrul Kayes for the second test against the Black Caps starting tomorrow.

15:44 The aftermath of the torrential rain has meant heavy surface flooding and slips are blanketing West Coast roads.

14:37 Crowd funding has raised more than $110,000 in less than a day to get a controversial Australia Day billboard image of two girls in hijabs back up.

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.

Share this video

Browse all videos

    Become a fan of RadioLIVE on Facebook and on Twitter.