World's Largest Pyramid - Bosnian Pyramid of the Sun

The Bosnian Pyramid of the Sun (Visocica Hill), is the first European pyramid to be discovered and is located in the heart of Bosnia, in the town of Visoko. The pyramid has all the elements: four perfectly shaped slopes pointing toward the cardinal points, a flat top and an entrance complex. On top of the pyramid are also the ruins of a Medieval walled town, once the base of a Bosnian king Tvrtko of Kotromanic (1338-1391).

Numerous scientific analysis suggest artificiality of the monument: satellite imagery, thermal inertia analysis that shows quick heat loss due to inner chambers and hallways; penetrating radar suggests straight passageways with 90 degrees intersections; water drainage and inner angles of 45 degrees characteristic for artificial objects. Geo-archaeological research uncovered man-made stone blocks that the pyramid walls.

Between 27,000 and 12,000 years ago, the Balkans were locked in the last Glacial maximum, a period of very cold and dry climate with glaciers in some of the mountain ranges. The only occupants were Upper Paleolithic hunters and gatherers who left behind open-air camp sites and traces of occupation in caves. These remains consist of simple stone tools, hearths, and remains of animals and plants that were consumed for food. These people did not have the tools or skills to engage in the construction of monumental architecture.

Mars Pits Revealed

Released in December, the image is among a series of new views snapped by MRO's HiRISE camera that show intriguing geological features on Mars. Each image covers a strip of Martian ground 3.7 miles (6 kilometers) wide and can reveal a detail about as small as a desk—and so far no sign of Star Wars monsters.

A sharp close-up of the the larger Martian pit revealed sediment and boulders (seen in a picture taken in fall 2010 by the Mars Reconnaissance Orbiter's HiRISE camera), as well as hints of sand that was blown inside and trapped in the deepest and darkest parts of the hole, according to NASA.

Car-size boulders punctuate the bottom of the smaller Martian pit (pictured in a fall 2010 HiRISE image). A bright sand dune laced with windblown ripples covers the sloping western side of the hole.

The two pits are believed to be relatively young, according to NASA. As the pits age, the slopes become shallow and widen as they material at the edges collapses inward.

Among other recently released pictures from NASA's Mars Reconnaisance Orbiter are these images of apparent mud volcanoes on in Acidalia Planitia, a large basin in Mars's northern lowlands (seen in a fall 2010 HiRISE picture).

Mud volcanoes—which also exist on Earth—form when wet, pressurized sediment buried at depth erupts onto the surface. (Related photo: "'Medusa' Worms Found in Mud Volcano.")

A gigantic trough (center) slices through Mars's Tharsis volcanic region in a fall 2010 picture by HiRISE.

Called a graben, the 1.2-mile-wide (2-kilometer-wide) depression formed when a block of the planet's crust dropped down between two faults. In this case, the tectonic movement left nearly vertical walls—each about a kilometer (0.6 mile) deep—on either side.

"From the scarcity of craters inside the graben, it's estimated to be less than a billion years old," principal investigator McEwen said. "This one is nicely defined because it cuts a well-preserved lava flow."

Partial Solar Eclipse

An unidentified employee of the Stefanik Observatory in Prague uses a projection shield to show the partial solar eclipse visible in the Czech capital during the morning on Tuesday, Jan. 4, 2011. The partial Sun eclipse started over the Czech Republic at about 08:00 CET and it will last until 10:50. In the culminating phase, up to 80 percent of the solar disc was obscured by the silhouette of the Moon passing between it and the Earth.

(AP Photo/CTK, Michal Kamaryt)