The young whippersnappers among our readers may not recall the day, but on August 12, 1960 the U.S. launched into orbit a 400 lb. metalized balloon, 100 feet in diameter. As it circled the earth every 90 minutes scientists at the Jet Propulsion Laboratory in California bounced microwave signals off the balloon which were detected at Bell Labs in New Jersey; they heard the “echo.” This launch was big news because, at the time, any successful rocket launch was amazing. Even more amazingly, Echo could be seen from the ground! Now, 70+ years later, there are hundreds of visible satellites. Here's a quick introduction into satellite-watching, worthy of sharing with your neighbors, kids, and colleagues. They will be impressed with the satellites and you.
