Motion Gallery

Celestial mechanics, medieval artwork

Celestial mechanics. Coloured historical artwork depicting a medieval pilgrim looking out from the sky (blue) to see the mechanics of the heavens (upper left). Cogs (yellow) can be seen in the left corner, with tracks that the Sun, moon and stars move along. This is an example of the classical geocentric (Ptolemaic) worldview that dates back to Ancient Greek times. It was replaced by the heliocentric (Copernican) model, proposed by Nicolaus Copernicus in 1543. This woodcut is from The Atmosphere by Camille Flammarion, published in 1873

© DETLEV VAN RAVENSWAAY/SCIENCE PHOTO LIBRARY

Koala, southern form (Phascolarctos cinereus) Clinging to tree Enclosure

Koala, southern form (Phascolarctos cinereus) Clinging to tree Enclosure, April, Waratah Park Earth Sanctuary, Duffy's Forest, New South Wales, Australia Note: Claws, paws for climbing trees. Sanctuary surrounded by electric fence to protect native animals from feral animals, natives roam free within the 2km of fence

© Miller, Steven David / Animals Animals/Earth Scenes

Dream Falls - Tahquamenon Falls State Park

Upper Tahquamenon Falls in Fall Color. Tahquamenon Falls State Park encompasses close to 50, 000 acres stretching over 13 miles. Most of this is undeveloped woodland without roads, buildings or power lines. The centerpiece of the park, and the very reason for its existence, is the Tahquamenon River with its waterfalls. The Upper Falls is one the largest waterfalls east of the Mississippi. It has a drop of nearly 50 feet and is more than 200 feet across. A maximum flow of more than 50, 000 gallons of water per second has been recorded cascading over these falls. Four miles downstream is the Lower Falls, a series of five smaller falls cascading around an island

© Matt Anderson Photography