Your Eyesight Will Improve Significantly

Cuzco lies in a bowl surrounded by mountains so steep that trains cannot climb the side; instead they online without prescription must zig-zag back and forth over a number of parallel tracks, each higher than the previous one, until arriving at the top.

Fun Sun Facts

hildren often draw the sun as a bright yellow circle that dominates everything else in the picture. Although the sun as seen in outer space is more white than yellow, the kids have got it right: the sun is by far the largest object in the solar system, containing 99.8%
of the system’s mass.

The sun’s white hue is symbolically apt. By human standards, it is ancient – about 4.5 billion years old. By its own standards, though, it is only middle-aged and will continue to radiate for perhaps another 5 billion years. During that time, its brightness will double. (And you thought you had it bad? Just think about the air-conditioning bills, not to mention that future generations will probably have to mow their lawns in a space suit.)

The surface of the sun, called the photosphere, has a temperature of about 5,800 Kelvin.

That’s 9,980 degrees Fahrenheit to you and me. And it gets even hotter: the temperature at the sun’s core hovers around 15.6 million Kelvin. (The sun’s heat is produced by thermonuclear reactions that convert hydrogen to helium.) The light from the sun can cause bleaching of the retina’s photosensitive pigments, causing temporary partial blindness – which is why we are taught not to look directly at the sun.

The Sun Gets in Your Eyes – Be Careful

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