Seismic Waves and Earth's Interior

When you look at a seismogram the wiggles you see are an indication that the ground is being, or was, vibrated by seismic waves. Seismic waves are propagating vibrations that carry energy from the source of the shaking outward in all directions. You can picture this concept by recalling the circular waves that spread over the surface of a pond when a stone is thrown into the water. An earthquake is a more complicated process than a stone splashing into water, and the seismic waves that are set up during an earthquake are more varied than those on the pond.

A Mystery from Earth's Red-Hot Inner Core

Geologists have long known that Earth's core, some 2,900 kilometers beneath our feet, is a dense, chemically laden ball of iron roughly the size of Mars. Pressures there bear down with the weight of 3.5

Here Are 7 Unsolved Mysteries That Will Send Chills Down Your Spine. The Twins In #6... BIZARRE.

It's easy to become obsessed with the unsolved mysteries of this Earth. Most people like to think that anything can be figured out or solved... but that's just not true. Take these 7 mysteries, for example. They have been mysteries for decades (if not longer). No matter how many experts have examined the cases, they are still shrouded in mystery.


1.) The Aluminum Wedge of Aiud

The greatest mysteries of PLUTO

Images of the dwarf planet Pluto taken by NASA's Hubble Space Telescope. CREDIT: NASA, ESA, and M. Buie (Southwest Research Institute)



Each week Life's Little Mysteries presents The Greatest Mysteries of the Cosmos, starting with our solar system.

mystery behind Taj Mahal

The Taj Mahal is a mausoleum located in Agra, India, built by Mughal emperor Shah Jahan in memory of his favorite wife, Mumtaz Mahal. The Taj Mahal (also "the Taj") is considered the finest example of Mughal architecture, a style that combines elements from Islamic, Indian and Persian architectural styles. In 1983, the Taj Mahal became a UNESCO World Heritage Site and was cited as "the jewel of Muslim art in India and one of the universally admired masterpieces of the world's heritage." While the white domed marble mausoleum is its most familiar component, the Taj Mahal is actually an integrated complex of structures.
 Building began around 1632 and was completed around 1653, and employed thousands of artisans and craftsmen. The construction of the Taj Mahal was entrusted to a board of architects under imperial supervision including Abd ul-Karim Ma'mur Khan, Makramat Khan, and Ustad Ahmad Lahauri. Lahauri is generally considered to be the principal designer.