Great Wall of China
Building a tree house in your backyard can take a lot of time and work, but imagine buildi...
Every seventy-five years, a bright jet of light races across the Earth's atmosphere. This long trail of bright light is called Halley's Comet. This famous comet was given its name for the astronomer Edmond Halley who discovered it in 1758. Halley found that the comets that appeared in 1531, 1607, and 1682 were the same object returning every 75-76 years. The first appearance of Halley's Comet was recorded in 240 BCE by Chinese astronomers. The last sighting of Halley's Comet was in 1986. Astronomers predict that the comet will return once again in 2061. Halley's Comet is the first periodic comet ever known, and it is the only comet that humans can see. Just think, you will be as old as your grandparents when Halley's Comet returns. Remember to keep a look out for it in 2061!
Building a tree house in your backyard can take a lot of time and work, but imagine buildi...
Before the invention of mechanical refrigeration systems, the only practical method for pr...
Meredith grew up in a neighborhood with lots of trees. There were old oaks and maples. The...