History of Interstate Highway

The interstate system was certified by the Federal-Aid Highway Act of 1956, generally identified as the National Interstate and Defense Highways Act of 1956. It was lobbied for by most important U.S. automobile manufacturers and championed by President Dwight D. Eisenhower, and was influenced by both his experiences as a young soldier crossing the country in 1919 next the route of the Lincoln Highway, and by his gratitude of the German autobahn network.

Planning for a system of new superhighways started in the late 1930s, even previous to federal commitment to build the Interstate highway system came in the 1950s. The Construction on the world's first public limited-access highway, the Bronx River Parkway, had started in New York as early as 1907. By the 1920s, longer highways like the New York City parkway system had been built as part of local or state highway systems. As automotive traffic increased, planners saw require for such an interrelated national system to add-on the existing, mostly non-freeway, U.S. Highway system. The General location of national system of interstate highways, together with all additional routes at urban areas selected in September, 1955 maps what became the interstate system, and is unofficially known as the Yellow Book.

Although the construction on the Interstate Highway system continues, it was authoritatively regarded as complete in 1991 (though 5.6 miles of the unique planned route remain either unconstructed or not yet open). The initial cost guess for the system was $25 billion over twelve years; it ended up costing $114 billion, taking 35 years to complete. As of 2004, the system contains over 42,700 miles (68,500 km) of roads, all at smallest amount four lanes wide.

A general view on Sunglasses

The Sunglasses may be made with moreover prescription or non-prescription (i.e. plano) lenses that are darkened to give protection against bright visible light. Good sunglasses should as well care for against ultraviolet light. As a result of changes in the atmosphere, ultraviolet levels are greatly higher than in the past and ultraviolet protection for eyes and skin is even more essential. It is likely to have lenses that look very dark and however offer little ultraviolet protection. Sunglasses differ greatly and many offer more style than protection.

The Glasses with photo-sensitive lenses, called photo chromic lenses, become darker in the presence of UV light. Unluckily, many car windshields care for the passengers from UV light, while not protects from bright visible light, making photo chromic lenses ineffective where they are most needed. Still, they offer the ease of not having to bring both clear glasses and sunglasses to those who often go indoors and outdoors during the course of a day.

The Light polarization is an added characteristic that can be applied to sunglass lenses. Polarization filters take away horizontal rays of light, which can cause glare. The Popular among fishermen and hunters, polarized sunglasses let wearers to see into water when generally glare or reflected light would be seen. The Polarized sunglasses may present a few difficulties for pilots in that reflections from water and the other structures often used to gauge altitude may be removed, or the instrument readings on liquid crystal displays can be blocked.

The real facts about Uranus

Uranus is the seventh planet from the Sun and the third biggest (by diameter). Uranus is bigger in diameter but smaller in mass than Neptune. Uranus is composed mainly of rock and various ices, with only about 15% hydrogen and a little helium (in compare to Jupiter and Saturn which are mostly hydrogen). Uranus (and Neptune) is in numerous ways alike to the cores of Jupiter and Saturn minus the huge liquid metallic hydrogen envelope. It appears that Uranus does not have a stony core like Jupiter and Saturn but rather that its material is more or less consistently distributed.

Like the other gas planets, Uranus has bands of clouds that carry around rapidly. But they are very faint, visible only with radical image improvement of the Voyager 2 pictures (right). Recent observations with HST (left) show bigger and more pronounced streaks. Additional HST observations show even more activity. Uranus is no longer the ordinary boring planet that Voyager saw! It now seems understandable that the differences are due to seasonal effects since the Sun is now at lesser Uranian latitude which may because more pronounced day/night weather effects. By 2007 the Sun will be unswervingly over Uranus's equator.

Like the additional gas planets, Uranus has rings. Like Jupiter's, they are extremely dark but like Saturn's they are composed of quite large particles ranging up to 10 meters in diameter additionally to fine dust. There are 11 recognized rings, all very faint; the brightest is identified as the Epsilon ring. The Uranian rings were the first after Saturn's to be discovered. This was of great importance since we now know that rings are a common feature of planets, not a peculiarity of Saturn alone. Uranus' fascinating field is odd in that it is not centered on the center of the planet and is tilted almost 60 degrees with respect to the axis of rotary motion. It is almost certainly generated by motion at relatively shallow depths within Uranus.