Two facts you need to know:
First, orbital debris is traveling at speeds many times faster than a bullet.
Second, humans and satellites aren't bulletproof.
Source: NASA
Debris left in orbit is often an unavoidable result of human activities in space. An orbital object is known as debris once it is unable to perform its function and move out of the way of potential collisions with other objects in orbit.
While the odds of any one orbital object colliding with another are currently low, a collision at orbital speeds will generate more debris, meaning more collisions, and the problem will become exponentially worse, an exponential problem dubbed Kessler Syndrome. On average, there is a debris collision each year, in addition to other fragmentation events, and these occurrences are becoming more frequent. Besides collisions, regular activities in space generate debris, which when combined with the wreckage from collision events, results in an average of over 1,500 new trackable pieces of debris each year.
This concept of the quantity of orbital debris increasing to irreversible levels is known as Kessler Syndrome. In 1978, NASA predicted that it would be 30 to 40 years until cascading collisions withheld orbits from humans for centuries. The expected debris field would destroy all functional satellites in those orbital paths and prevent any additional launches from completing their mission. This entails loss of access to existing technologies, such as GPS, weather prediction, observation, telecommunications, and more. The process of cascading collisions has begun, and already the orbit of 560 to 620 miles (900 to 1,000 kilometers) is considered to be at critical mass for debris.
Current proposed approaches to the problem of orbital debris and collisions fall into three main categories: debris avoidance, reduction of future debris creation, and removal of debris already in orbit. Debris avoidance is limited by proper early detection, finite fuel supply, and limited maneuvering capabilities of the craft in harm's way.
Source: European Space Agency
While reducing future debris is good moving forward, it does not solve the problem which already exists or prevent accidents and collisions from creating more debris. The crucial step to prevent Kessler Syndrome is active debris removal (ADR) in orbit. Common proposed solutions involve removing debris from orbit by lowering both the debris and recovering satellites into the atmosphere. At KMI, we believe more efficient and scalable solutions are possible.