How Dangerous Space Junk’s are

 “Space debris is a big problem for satellite operations: it poses serious risks to a wide array of satellites critical to society there is more concern and awareness of space-junk issues, and more recognition that atmospheric drag is the major uncertainty in tracking it.” Rockets used to launch spacecraft, and spacecraft that decay or collide while in orbit create space debris that is difficult to remove. Tiny fragments of these spacecraft can puncture satellites and other orbiting assets.

SPACE DEBRIS AHEAD

More than 500,000 pieces of debris, or “space junk,” are tracked as they orbit the Earth. They all travel at speeds up to 17,500 Humans produce an incredible amount of trash on Earth. In the United States alone, the average person throws away more than 4 pounds of trash every day. The country as a whole produces 251 million tons of garbage in one year [source: EPA].Because we have our own issues on the ground with littering and overflowing landfills, we might not think too much about space junk aside from a few space stations and a handful of satellites in orbit. But NASA claims there are potentially millions of objects, both small and large, orbiting Earth in a giant cloud of junk. Barring anti-satellite (ASAT) tests, leftover spacecraft that were never deorbited pose the biggest threat as they, and their orbits, decay over time. Russia has a high number of dead satellites still in orbit around the planet that could collide with other satellites, creating an innumerable spike in debris levels. Today, the majority of space debris in orbit was created from two events: the Iridium33 and Kosmos 2251 satellite collision in 2009 and a Chinese ASAT test in 2007. Based on current trends, the risk of future collisions still persists.

NASA and five other members of the Interagency Space Debris Coordination Committee (IADC) produced six different models of future space debris. Liou said the debris population at the 1-cm level is approximately 500,000 while, if you go down to the 1-mm level, the number is estimated to be a staggering 100 million. The models all predicted that, as is, the debris situation is set to get worse.

“The results from those six models, they are consistent with each other, meaning even with no future explosions and the global 90 percent compliance of the post-mission disposal measures — including the 25-year rule — the debris population in [Low Earth Orbit] (LEO) is expected to increase in the next 200 yearsThe Defense Advanced Research Projects Agency (DARPA) is testing a “cellular” satellite design where small “satlets” can form together to comprise a satellite. David Barnhart, program manager for DARPA Phoenix said the idea,
 The Dangers of Space Junk

Although it's hard to believe, many of these objects travel around the Earth at speeds more than 22,000 miles an hour. Anything traveling at a velocity this high would cause a considerable amount of damage to a spacecraft if a direct hit occurred. Even a tiny fleck of paint traveling at such a speed is capable of boring a quarter-inch hole into the window of a space station.

Because there are so many objects flying around up there, there's concern that collisions between debris will only produce more fragments. Even if we stopped launching spacecraft right now and didn't send a single object into orbit, the amount of debris in space would remain constant until 2055

The good news

most space junk is located between 550 and 625 miles above the Earth -- the International Space Station flies in orbit at 250 miles high, while space shuttles usually only reach 375 miles above Earth. Space programs are also working on rocket designs that limit the amount of debris created during a launch.

For those of us on Earth, is there a possibility space junk could fall back to the ground? Everything in orbit will eventually be pulled back down by Earth's gravity -- when that happens depends on how high the object is and how fast it's going. The higher the altitude, the longer the object will take to fall, and it'll take even longer the faster it's speeding around the Earth. These objects could stay in orbit for thousands of years. And the risks of getting hit on the head? Fortunately, most debris burns up during reentry, and no one has ever been killed by space debris.add your comments below,,,