Tens of thousands of reminiscing pieces of metal from previous collisions of dead satellites are now orbiting the earth, and this space debris layer has kept thickening since the dawn of the space age (in the 1950s). It keeps growing into an imminent threat for both crewed and uncrewed space missions. During the Sputnik-1 mission in 1957, the first piece of space debris was released by humans, which remained in orbit and combusted toward the earth atmosphere after a few days, and it was from this point the space debris layer kept on broadening.
Especially over the 37 past years, satellites were sent out for commercial, educational, security and environmental purposes. During this time, researchers have characterised that the population of space debris rises with time- in correspondence with the hazardous impacts of these conflicting layers. Space Debris is known in different names: ‘Space Waste’, ‘Space Junk’, ‘Space Garbage’, ‘Space Trash’ and more, all meaning- debris of damaged, worn out and old machinery that no longer serves a useful role or natural pieces of meteoroids, aimlessly floating around the earth’s orbit.
Especially over the 37 past years, satellites were sent out for commercial, educational, security and environmental purposes. During this time, researchers have characterised that the population of space debris rises with time- in correspondence with the hazardous impacts of these conflicting layers. Space Debris is known in different names: ‘Space Waste’, ‘Space Junk’, ‘Space Garbage’, ‘Space Trash’ and more, all meaning- debris of damaged, worn out and old machinery that no longer serves a useful role or natural pieces of meteoroids, aimlessly floating around the earth’s orbit.
Types of Space Debris
Space Debris is of two main types: Natural Space Debris and Artificial Space Debris. Natural Debris are meteoroids- the pieces of asteroidal and cometary materials- that are floating in space. When they penetrate the earth’s atmosphere, they are called ‘Meteors’. On the other hand, Artificial Space Debris is any piece of human-made object that is usually orbiting around the earth’s atmosphere that does not serve any functional purpose. In terms of size, NASA mentioned that are approximately 23,000 space debris pieces that are larger than a softball, half a million marble-sized pieces (4.0 inches or larger), 100 million pieces of 0.04-inch diameter and more pieces that are smaller than a micrometre (0.000039 of an inch in diameter).
The formation of Artificial Space Debris can be due to many reasons, like:
- Accidental or deliberate cast-aways like human waste or tools
- Dead Satellites (Satellites that have zero functional lifetime)
- Deterioration or degradation particles like peeled paint fragments
- Failed missions to space (dysfunctional or failed spacecraft or satellites)
- Fragments from accidental or deliberate explosions and collisions
- Launch Hardware like shrouds, nose cones, bolts, payload covers etc.
- Rocket stage disposals
- Solid propellant slags and more.
Is Space Debris A Problem?
It is a closely imminent danger that unmonitored space debris has a hugely detrimental impact because it can inflict collisions with functioning or active crewed or uncrewed spacecraft and satellites. They can also make the optical surface corrode by damaging telescope mirrors and reducing the productivity of solar cells. Particles of space debris can also create craters, pits, and related damages in windows and walls of spacecraft, which result in immediate and costly replacements of spacecraft parts. It was researched that a piece of space debris that is larger than a single centimetre can penetrate walls of existing space-accommodated equipment like crafts, satellites and rockets. As the collision velocities are so high in space, a simple paint flake can create a crater in the windscreen of a craft; therefore, the impact of space debris on future space travels must strictly not be neglected. It was also found that space debris interrupts astronomical imaging by creating light trails on images, limiting the aesthetic and scientific value of the images. This has also impacted the astronomers’ ability to see faint objects (like far-away galaxies).
What Can Be Done to Mitigate The Impacts of Orbital Debris?
Not many technology experts and space enthusiasts have developed the aptest solution to overcome this hazard, but a few technology practitioners show glimpses of hope for outstanding solutions in the near future. There are a few discoveries that are still in the developing phase aimed to tackle impacts related to space debris that is used by a few space players, like:
- Attaching Tethers that is artificially tailed onto larger debris objects to increase the drag
- Computer Programs like possible impactful collision predictors that indicate safer navigation routes where the spacecraft can flee from harm’s way using thruster rockets.
- Debris Shields that enabled additional protection for the spacecraft against space debris like the Whipple Shield (founded by Astronomer Fred Whipple)
- Ground-based lasers to push little particles of debris to lower orbits
- Space Tugs to catch large objects in the space debris layer
- Sponges are giant sponge-like objects that soak up small debris particles
- Tracking Networks like DoD’s Space Surveillance Network that track debris networks and indicate the locations of impactful debris particles (which are larger than 100 mm), this technology is not 100% reliable yet
Is There Hope for Space Debris Technology?
Certainly! Many technology experts are collaborating with Space Agencies to find reliable and innovative technology solutions to mitigate the impacts, risks and financial conundrums related to Space Debris. Such discoveries will ensure the earth’s orbit is clean and preserved so that the next generations too can enjoy its benefits.
