On October 4, 1957, the world witnessed a groundbreaking event: the launch of Sputnik I, the first artificial satellite. Although it burned up in the atmosphere just three months later, this marked the beginning of space exploration. However, it also started a new problem: space debris. Today, thousands of satellites and pieces of junk orbit the Earth, posing risks to operational satellites, GPS systems, and even astronauts.
Most space junk is found within 2,000 kilometers of Earth’s surface. Currently, there are over 22,000 objects larger than a softball and more than half a million pieces larger than a marble. These objects travel at speeds of 7 to 8 kilometers per second, and collisions can occur at an average speed of about 10 kilometers per second. The impact of such a collision is like a midsize car traveling nearly 200 kilometers per hour, which can destroy any satellite in orbit.
Swiss astronaut Claude Nicollier, who has been on four space flights, knows these dangers well. He points out that only large debris is tracked, and sometimes spacecraft orbits need adjustments to avoid collisions. Although there have been no serious incidents with manned spacecraft, a notable collision in 2009 between two satellites created 2,000 new pieces of debris.
Switzerland has recognized the growing threat of space debris and launched a program called Clean Space One. This mission aims to demonstrate the ability to remove space junk. The focus is on retrieving one of two Swiss satellites, including a small satellite named Swiss Cube. The Swiss are determined to keep their national identity clean by ensuring no junk is left floating in space.
The main goal of Clean Space One is to prove that a “janitor satellite” can be sent into space to capture a piece of debris, specifically Swiss Cube, and bring it back into the atmosphere to burn up. This ambitious project requires advanced technology and innovative engineering.
To achieve its mission, Clean Space One uses an efficient propulsion system developed by Professor Herbert Shea, an expert in micro mechanics. The system uses electro propulsion, which emits single electrically charged atoms and accelerates them with an electric field. This method allows the satellite to gradually build up speed, reaching significant velocities over time due to the negligible friction in space.
Once in orbit, the next challenge is to capture the tumbling space junk without creating more debris. The team plans to use a system similar to an octopus arm, designed to wrap around and securely hold the debris. This innovative grabber will be soft and flexible, allowing it to adapt to various shapes and sizes of space junk.
While the mission may sound ambitious, the Swiss team understands the vastness of the space junk problem. Their immediate goal is to start systematically removing large debris, targeting five or more pieces per year starting in 2020. This effort aims to reduce the increasing density of debris in low Earth orbit, ensuring that space remains accessible for future exploration and use.
The Clean Space One initiative is a significant step toward addressing the growing issue of space debris. By developing innovative technologies and strategies for debris removal, Switzerland is not only protecting its own satellites but also contributing to the sustainability of space for future generations. As the world continues to explore the cosmos, initiatives like Clean Space One will be crucial in maintaining a safe and navigable environment beyond our planet.
Imagine you are part of a team tasked with cleaning up space junk. Create a simple simulation using everyday materials like marbles, balls, and a large sheet to represent space. Place the marbles and balls on the sheet and gently shake it to simulate the movement of space debris. Your task is to devise a method to remove the “junk” without disturbing the other objects. Discuss your strategy with your classmates and explain how it relates to the Clean Space One mission.
Using the information that space debris travels at speeds of 7 to 8 kilometers per second, calculate the kinetic energy of a piece of debris with a mass of 1 kg. Use the formula for kinetic energy: $$ KE = frac{1}{2}mv^2 $$ where $m$ is mass and $v$ is velocity. Discuss how this energy compares to everyday objects and why it poses a threat to satellites.
In groups, brainstorm and sketch a design for a device that could capture space debris. Consider the challenges of capturing objects moving at high speeds and in different orientations. Present your design to the class, explaining how it would work and what materials you would use. Compare your ideas with the octopus arm concept used in Clean Space One.
Engage in a classroom debate about the responsibility of countries to clean up their own space debris. Consider the costs, benefits, and potential international cooperation required. Discuss whether initiatives like Clean Space One should be mandatory for all countries launching satellites.
Research another initiative or technology aimed at addressing the space debris problem. Prepare a short report or presentation on your findings, highlighting the similarities and differences with the Swiss Clean Space One project. Share your insights with the class and discuss the potential impact of these technologies on future space exploration.
Space – The vast, seemingly infinite expanse that exists beyond Earth’s atmosphere, where celestial bodies like stars, planets, and galaxies are found. – Astronomers use telescopes to study the mysteries of space and learn more about the universe.
Junk – Unwanted or discarded material, often referring to debris in space that can pose a threat to satellites and other spacecraft. – Scientists are concerned about the increasing amount of space junk orbiting the Earth, which could damage operational satellites.
Debris – Scattered fragments, typically of something wrecked or destroyed, which in space can include defunct satellites and spent rocket stages. – The collision between two satellites created a cloud of debris that now poses a risk to other spacecraft.
Satellite – An artificial object placed into orbit around a celestial body, such as Earth, to collect information or for communication purposes. – The weather satellite provides crucial data that helps meteorologists predict storms and other weather patterns.
Orbit – The curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution. – The International Space Station maintains a low Earth orbit, allowing it to circle the planet approximately every 90 minutes.
Technology – The application of scientific knowledge for practical purposes, especially in industry, including the development of tools and machines. – Advances in technology have enabled scientists to explore distant planets and gather data from the far reaches of the solar system.
Propulsion – The action of driving or pushing forward, often referring to the mechanisms that move spacecraft through space. – Rocket engines provide the necessary propulsion to launch satellites into orbit around the Earth.
Capture – The act of taking or seizing something, often used in the context of collecting space debris or other objects in space. – Engineers are designing new methods to capture space debris and reduce the risk of collisions with active satellites.
Clean – Free from unwanted matter or pollution, often referring to efforts to remove debris from the environment, including space. – Initiatives to clean space aim to remove defunct satellites and other debris to ensure safer conditions for future missions.
Environment – The natural world or ecosystem, including all living and non-living things, which can be affected by human activities. – Protecting the environment is crucial for maintaining biodiversity and ensuring the health of our planet for future generations.
