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Space missions are fascinating and the arrival of reusable rockets could only mean more and more satellites getting launched into space. That might sound amazing, but we are actually creating a great threat of collision of satellites. While we are launching these impressive satellites, we are also creating a lot of junk in space and not clearing it up. This debris could damage the active satellites or worse, it could pose a serious threat to the astronauts in space. So how to track this tiny debris? How are we going to clear up the mess?
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| View of the Earth's upper atmosphere |
Space debris
Space debris or space junk is the result of launching satellites and rockets from our planet to outer space or to the outer atmosphere of the Earth. So Space junks could be small like the tiny instruments which got damaged in Space or it could even be the dead satellites (i.e) that have completed their mission and left in orbit or that have failed completely. Even the rocket launches are leaving an enormous amount of Space debris during their stage separations. Some debris could be formed even from the result of satellites collide against each other and even the anti-satellite missions which have been planned and launched have been a huge failure because blowing the satellites created even more debris in space.
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| Space Debris surrounding the Earth |
About 2000 active satellites are revolving around our planet and there are also 3000 dead satellites scattering the debris in space. Scientists and Astronomers have found a way to detect the space junks revolving around our planet and they have identified more than 35,000 pieces of space debris larger than 10 centimeters in diameter which could cause accidents on our active satellites. And worse, there are 128 million small pieces that are larger than 1 millimeter in the upper atmosphere which could also cause some serious problems on the satellites in space.
Even the smaller pieces could cause havoc in satellites because of the high speed with which the space junks are revolving around the Earth. This could also risk the lives of astronauts in the International Space Station (ISS). But luckily the astronauts could perform the debris avoidance maneuver in the ISS, which could help the ISS to move out of the orbit of the debris. But it can't be done in every satellite as a single avoidance maneuver could deplete the fuel in the satellites. Tracking and cleaning the space junks is a critical task to avoid the collision of satellites.
Why Space debris is a problem?
Space is a very vast area, so what is the problem with having this space debris? The problem is the space might be large, but the satellites and space junks are stuck in a very tiny part of our upper atmosphere. We got to have a clear catalog of space junks revolving around the Planet. Even the debris which is 1 millimeter in size could create serious damage to an active satellite or a spacecraft because the junks might be traveling at higher speeds of up to 28160 kmph (17,500mph). But we don't have to worry about all the space debris because most of them will be taken care of by the atmosphere.
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| Space Debris posing threat to Astronauts in the ISS |
Most of the space debris which comes closer to our outer atmosphere will be attracted by the gravitational pull of the Earth. When the smaller debris is attracted by the gravity of the Earth, it will be pulled lower into our atmosphere and it will be burnt due to the air friction and high atmospheric pressure. The heavier fragments will stay firm and fall into the ocean because the surface of the Earth is mostly water.
There wasn't any serious damage caused by the space junk so far. But as time goes on, we are going to launch more and more rockets and satellites into outer space, which could only produce more space junk. With private agencies like SpaceX planning to launch the StarLink project to provide low-cost internet access all across the world by deploying 42,000 satellites in our outer atmosphere the problem of space debris could get only worse.
Tracking Space Debris
Tracking space debris is definitely not an easy job to do because the space junks are tiny. Detecting the course of the debris is an important job because of the presence of active satellites in the upper atmosphere. These space junks could cause the devastation of the satellites, so tracking the space junks is taken care of by NASA's department of defense. They maintain the catalog of objects that are floating or revolving in our upper atmosphere by using a Radar system in the pacific.
The new and cheap method is proposed by the United Kingdom Space Agency (UKSA) is proven to be efficient in detecting the trajectory of space debris. The proposed system uses optical technology to detect the debris and predict the trajectory of the debris by applying Artificial Intelligence. The information obtained from the camera is updated in the space debris database. This method is proven to be cost-efficient and it might give us the data about the possible collisions by the space debris. By knowing this possible collision course, the satellites could perform an orbit-shifting maneuver.
How do you clean the debris in space?
There are many ways proposed by several private companies to clean up the mess in the space. The major ideas were to use the atmosphere to burn up the debris which would be collected by the nets or magnets. Another idea proposed by the Japanese scientists is to use laser beams to fire at debris which will reduce its speed and allow it to get into our atmosphere. But these are just mere ideas, the governments are not ready to make these ideas a reality because these missions could require enormous funding.
To avoid the creation of more space debris, the satellites are now being launched within the Earth's atmosphere so that the satellites get burned down after the completion of their mission. The UN has asked every space agency to pull its satellites out of their orbit and remove them from space within 25 years after completing their missions.
Conclusion:
Space debris is not a threat for us just now, but it is already posing a great danger to Astronauts on the ISS and other capsules in space. After the Starlink mission, the upper atmosphere is only going to get aggregated with junks. This might affect our space tourism as it might pose a threat to the passengers on board. Space debris might also just jeopardize our plan of great infrastructures like the space elevator or the skyhooks. Earth orbit is crucial in studying the Earth, so losing it would be a great loss. We might have to find a way to clear the junks on the orbit.
