I learned about something called axial precession in astronomy class several years ago, which is the idea that as something rotates along its axis, it will slowly trace out a cone if the weight of the object isn't equally distributed. In the case of Earth, Earth isn't a perfect sphere as many of us may think it is -- it actually bulges out in the middle enough for it to allow this phenomenon to occur. At the time, all I really took from this concept was how fascinating it is for the north axial pole to move 1° every 72 years from where it is now, and complete one full cycle every 26 000 years. However, I never managed to understand how this concept could fit in to my understanding of why ice ages[1] occur, and why they too follow a specific ...

This is the Northrop Grumman B-2 Spirit (stealth bomber). This machine is capable of pin-point strikes on most any hardened target available such as underground bunkers. Needless to say, it is also capable of delivering nuclear weapons.

This stealthy aircraft was designed in a way that enemies could not anticipate its arrival, but its 22,600 Kg bomb load and a multitude of nuclear missiles would ensure they'd know when it had arrived. Named the B-2 Spirit, its advantage in battle is derived from its designation spirit; it operates like a ghost.

Engines: Four General Electric F118-GE-100 turbofans of 17,300 lbs. thrust each
Wingspan: 172 ft.
Length: 69 ft.
Height: 17 ft.
Speed: High subsonic
Takeoff weight: 336,500 lbs. ...

The bullet ant, or Paraponera clavata, lives throughout Central and South America. What makes this ant a formidable insect are its large mandibles and stinger. The bullet ant is one of the largest ants, growing to a length of just under 1 inch. Most notable about the ant is its ability to produce an excruciating sting.

Birthmarks are congenital marks on the skin that appear at birth and occasionally disappears spontaneously. The term nevus refers to a benign cutaneous tumor consisting of blood capillaries. Such tumors, which rarely spread from their original site and are not dangerous, vary in color according to whether the capillaries composing them carry arterial or venous blood. The popularly termed cherry marks and port-wine stains (shown below) are nevi on a level with the surface of the skin. Certain other vascular nevi, commonly known as strawberry or raspberry marks (scientifically known as hemangiomas), are slightly elevated above the surface. These can appear anywhere on the body's surface, including the airway within the nose. The former Soviet ...

The Loretto staircase – built within the Loretto Chapel in New Mexico, USA – is by far the most remarkable staircase ever built. It features a double-helical spiral structure that spans 20 feet in altitude, and remains intact without the use of a central pole. The staircase is built mostly out of wood and is held together by wooden pegs and glue rather than nails or other hardware.

The staircase is venerated by Catholics as being miraculous, not due to its marvel, but based on the events that have been passed down by the Sisters of chapel ever since it was built in the late 1800s. Before the construction of the Chapel could be completed, the architect responsible for the building's design had suddenly died, leaving the nuns without access to ...

The photo shown below was taken at a market in Shanghai, China.

Can you guess what they are?


Water caltrops (Trapa natans) are the seeds of a floating annual aquatic plant that's native to warm temperate parts of Eurasia and Africa. The plant grows in slow-moving water up to 5 m deep, and bear an ornately shaped fruit that resembles the head of a bull or the silhouette of a flying bat. Each fruit contains a single very large, starchy seed. T. natans and T. bicornis have been cultivated in China and the Indian subcontinent for at least 3,000 years for the edible seeds that are used in pastries, served steamed or boiled from street vendors, and even as a remedy for inebriation.

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Chironex fleckeri, commonly known as sea wasp, is a species of deadly venomous box jellyfish found in coastal waters from northern Australia to the Philippines. It has been described as the most lethal jellyfish in the world, with at least 63 known deaths in Australia from 1884 to 1996.

Notorious for its sting, C. fleckeri has tentacles up to 3 m (9.8 ft) long covered with millions of cnidocytes which, on contact, release microscopic darts delivering an extremely powerful venom. Being stung commonly results in excruciating pain, and if the sting area is significant, an untreated victim may die in two to five minutes! The amount of venom in one animal is said to be enough to kill 60 adult humans (although most stings are mild). ...

Rattlesnakes are a group of venomous snakes native to the Americas known for their loud rattling tail. The tip of their tail, known as the rattle (middle), vibrates to deter predators or serves as a warning to passers-by.

The rattle is composed of a series of hollow, interlocked segments made of keratin, which are created by modifying the scales that cover the tip of the tail. The contraction of special "shaker" muscles in the tail causes these segments to vibrate against one another, making the rattling noise (which is amplified because the segments are hollow) in a behavior known as tail vibration. The muscles that cause the rattle to shake are some of the fastest known, firing 50 times per second on average, sustained for up to three hour ...