In 2009, US - Iridium 33 satellite collided with Russia's Kosmos 2251. This resulted in thousands of new space debris ! With an estimated 7,50,000 bits of old satellites and rockets circling around the Earth at about 18,000 miles per hour , any collision could instantly shatter the multi million dollar satellite industry !!

        Space debris is an artificial material that is orbiting Earth but is no longer functional. This material can be as large as a discarded rocket stage or as small as a microscopic chip. It is also called space garbage or space junk.  

Space junk's rise eyesore for many     

         According to the ESA, there are currently 36,500 space debris objects being tracked that are greater than 10cm in diameter, and a further 1 million objects being tracked that are between 1 cm and 10cm in diameter. Space debris is having a significant impact on space safety and sustainability.

                The space industry is growing rapidly, most notably within LEO where, in recent years, there has been a big increase in commercial satellite constellations. As the Earth's orbit becomes more congested, the need to tackle the problem of space debris has increased.

      According to the ESA, space a debris include:

•Pyload: these are mainly  satellites. This includes  fragments produced by wear and tear and collisions.

• Rockets: remains of stages used to propel missions in orbit.

• Mission-related objects: for example, dropped tools, screws, cables, cameras, etc.

It' s time to rethink problems with space junks

        Space scientists have been uttering the word " Kessler Syndrome" for a while now. This word tells us the pulse of space technology. Look deeper and witness a fear of this syndrome.The overpopulation of space with objects and debris is referred to as Kessler Syndrome!

       Space debris gives rise to several problems . First of all it is a great  threat to Marine Life. Space junks when they fall into the oceans, they can be a great  threat to marine life. Even space garbage causes pollution.

          Further  the floating space debris is a potential hazard for operational satellites. When space junk  collides  with satellites, it may make  the satellites nonfunctional.

         Above all, the concentration  of space debris in specific orbital zones can limit the availability of desirable orbital slots for future missions.

          Eventually  satellite operators and space agencies find it difficult to accurately track and predict the orbits of objects in space.

Methods of removal of space debris

                     Dead satellites are expensive to remove. So retired satellites are often left in a low-Earth orbit. According to NASA  their presence poses a growing threat to both future satellite launches and crewed space missions. 

        The international space station (ISS) has to regularly adjust its position to avoid space debris. One way to get rid of this orbital refuse is to send space vehicles to capture and ‘deorbit’ the junk, using tools such as a net, harpoon or robotic arm.

        Today China and Japan are two countries pioneered in removal of space debris.           

          ELSA-d is the world’s first commercial mission from Japan  to prove the core technologies necessary for removing space junk  in LEO. The mission, which consists of two satellites — a servicer designed to safely remove debris from orbit and a client that serves as a piece of replica debris.

          Astroscale’s End-of-Life Services by Astroscale-Multi (ELSA-M) servicer is specifically designed for the servicing of constellation satellites that are fitted with a compatible docking plate, including OneWeb's JoeySat.

             Astroscale’s ELSA-d demonstration mission is currently in low Earth orbit, preparing for a series of complex rendezvous and close proximity debris capture and release manoeuvres this summer. Much of the innovative autonomous technology undergoing testing during ELSA-d this year will continue to evolve, at pace. 

Can the world solve the space debris puzzle ?

              When satellite technology was just born, space debris did not seem a serious technical hazard. But now the scenario is different. Taking disapproving note that space debris is growing at a faster pace, today every country is serious about it.

In fact, Russia is one of the top countries in the creation of space debris ! In November 2021, Russia conducted a widely criticised anti-satellite test on Cosmos 1408 that left behind an estimated 1,500 pieces of space junk!

        For the sake of debris-avoidance activity , NASA on October 24, 2021, increased the station’s altitude by two-tenths of a mile at apogee (the farthest point in an orbit around Earth) and eight-tenths of a mile at perigee (the closest point in an

orbit around Earth).

             The Russian space agency Is going ahead with a plan to spend $2 billion to clean up space debris. In a post on its Facebook page, the agency disclosed that Russia intends to develop a special orbital pod that would sweep away satellite debris that's now circling the Earth.

             Not much more is known about how the craft would accomplish its mission but the cleaning satellite is supposed to work on nuclear power. It also would be capable of working up to 15 years, according to Energia, the Russian company building the cleaning satellite. The current plan is to have the craft operational within the end of 2023.

India's step towards space debris dispute

          In 2022, ISRO set up the System for Safe and Sustainable Operations Management (IS 4 OM) to continually monitor objects causing collision threats, predict the evolution of space debris, and mitigate the risk posed by space debris.

          Project "NETRA" developed by ISRO  is also an early warning system in space to detect debris and other hazards to Indian satellites.

             ISRO has also carried out 21 collision avoidance efforts  on Indian operational space assets in 2022 to avoid collisions with other space objects.

Conclusion

         The transformation in awareness of space sustainability over the past decade has been truly remarkable. Space debris, once considered a fringe topic, has now become a key priority for government leadership worldwide.

 

References:

1)Blogs on space debris by astrascale.com

2)" Russia Plans To Clean Space Junk From Earth Orbit " by cbsnews.com

3) Article on space debris by drishtiias.com/..