Answer: With the increasing number of satellites and other objects in orbit, orbital crowding and space debris are becoming major issues that threaten the sustainability of outer space. There are currently more than 26,000 objects larger than 10 cm in orbit, and over 500,000 pieces of debris smaller than 1 cm, which pose significant risks to space assets.

• Space sustainability refers to the responsible and long-term use of outer space resources, while ensuring the preservation of the space environment and its ability to support present and future generations.
• It encompasses a wide range of practices, including the safe and sustainable operation of spacecraft and space infrastructure, the responsible management of space debris and other forms of space pollution, and the promotion of international cooperation and collaboration in space activities.

• Increase space debris: Orbital crowding can lead to an increase in the amount of space debris, which can damage or interfere with satellites or another spacecraft in the same orbit.
• Congestion: Orbital crowding can also lead to congestion, which can make it difficult for spacecraft to manoeuvre and prevent them from accessing their orbital pathway.
• Risk to astronauts: The amount of radiation exposure can be increased, which can lead to damage to both humans in space and spacecraft.
• Kessler syndrome: Physical crowding of orbits can lead to a chain reaction called Kessler syndrome, where debris collisions create more debris and make space activities more hazardous.

• Establish an international agreement on the use of space resources: This would help to ensure that all countries are on the same platform when it comes to the use of space resources, and it could provide a framework for sustainable development.
• Minimize space debris: Countries should work together to develop effective debris removal systems, such as the Space Debris Removal System (SDRS).
• Promote responsible resource use: Countries should work together to develop more efficient and eco-friendly technologies, and they should also ensure that resources are used in a safe and sustainable manner.
• Make use of reusable technology: Reusable technology can reduce the number of materials and resources needed for space exploration, and it can also help to reduce waste. Examples of reusable technology include reusable rockets, reusable satellites, and reusable rovers.

Space sustainability is crucial for the continued peaceful and socioeconomic benefits of outer space. Measures like guidelines, ratings, and initiatives towards space situational awareness and debris monitoring can promote space sustainability and mitigate the threats posed by orbital crowding and space debris.