How Much Space Junk Are There? Will the Cosmic Debris Affect Us on Earth?

Throughout human history, there have only been around 6,300 successful rocket launches, which have resulted in millions of fragments and debris that no longer serve a useful function. With tens of thousands more launches planned over the coming years, a massive increase in space junk raises severe concerns over space sustainability.

How Much Space Junk Orbits the Earth?

Since 1957, successful rocket launches have delivered 14,450 satellites into Earth's orbit, according to the European Space Agency. Over that same period, more than 630 collisions, explosions, or other unplanned events caused objects to break apart.

The Combined Force Space Component Command (CFSCC) has tracked and cataloged about 32,750 objects floating in Earth's orbit. These objects are observed by monitoring reflections from the Sun and fed into an algorithm. This system determines the size of an object and its distance from our planet. The CFSCC team was able to pick up a thing that was only 19.7 inches (50 centimeters) in size and traveled at 1.86 miles per second (3 kilometers per second) 22,236.4 miles (35,786 kilometers) away in geostationary orbit.

These figures may already be overwhelming, but the real problem lies in the space junk we cannot see. Based on statistical models released by ESA's space debris office, there are about 36,500 objects larger than 3.9 inches (10 centimeters), 1 million things between 0.39-3.9 inches (1-10 centimeters), and 130 million objects between 0.04-0.39 inch (1 millimeter to 1 centimeter).

This debris can be anything from paint flecks from space rockets or small fragments made during in-orbit impacts. Although minimal, they travel faster than a bullet, which can cause incredible damage to those in orbit.

How Big a Problem is Space Debris?

ESA reports that there have been over 560 fragmentation incidents since 1961, mostly caused by fuel explosions in rocket stages. In direct collisions, there have only been seven cases, the most serious being the destruction of an inactive Russian satellite, Kosmos 2251, and the operational satellite Iridium 33.

Technically speaking, it is the small fragments that pose the greatest danger. Micrometeorites, such as paint flakes and solidified droplets of antifreeze, can damage solar panels used by active satellites. There are also other dangerous debris, like vestiges of solid fuel, which float about in space and are highly flammable. This debris can cause damage and spread pollutants into the atmosphere if they explode.

There are also Russian satellites that contain nuclear batteries with radioactive materials. They have the potential to cause dangerous contamination if they return to Earth. The re-entry heat destroys most of this space debris before it reaches the Earth, but larger fragments can reach the surface and bring considerable damage.

Space junk can cause environmental dangers here on Earth by releasing compositional chemicals into the atmosphere during reentry. Since they weaken the ozone layer, they threaten space exploration and future human generations.

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