![]() About half of these are active payloads, but there are also around 34,000 pieces of " space junk" ranging in size from as large as 30 feet, down to about the size of a softball, and literally millions of smaller pieces that could nonetheless prove disastrous if they hit another orbiting object. Since then, there are now roughly 6,000 satellites now in orbit around Earth. The very first satellite was Sputnik, launched in October 1957. This should not be too surprising when you consider just how many objects are now circling the Earth. ![]() or from two hours to 30 minutes before sunrise, you will sight as many 15 to 30 satellites, ranging in brightness from as bright as the brightest stars (zero or first magnitude) down to moderately faint objects of around fourth magnitude. Right now, there is a fair chance that if you go out and carefully study the sky between 30 minutes and two hours after sunset. Most meteors first appear at an altitude of 80 miles (130 kilometers) and disappear about a second later at perhaps 40 miles (65 km). Such objects are usually particles no larger than a pebble or sand grain, that crash into our upper atmosphere at high speeds of up to 45 miles per second (that's about 162,000 mph or 260,000 kph) their kinetic energy is converted almost instantly to light creating the effect of a shooting star. We call these meteors today, although the term "falling star" and "shooting star" are still widely used. Ancient stargazers believed that such a sight was a star falling from its fixed position in the sky. Perhaps you'll catch a glimpse of an extraterrestrial intruder a sudden streak of light, lasting no more than a second or two at most and possibly leaving a brief incandescent trail in its wake. But you also may also see some other interesting sights, some natural like tiny falling rocks and others less so, like China's Tianhe space station just a week after it launched into space. ![]() Once your eyes have fully adapted to the dark, you might be able to count several hundred stars of varying degrees of brightness. ![]()
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