How are we protecting astronauts from deadly space debris?, Pg9

Key Highlights:

• Micrometeoroids and Orbital Debris (MMOD) pose a constant threat to spacecraft and space stations.
• A piece of debris recently struck the Chinese crewed vehicle Shenzhou-20, causing a minor crack.
• Orbital debris consists of human-made objects in Earth’s orbit that no longer serve any useful purpose.
• The Inter-Agency Space Debris Coordination Committee (IADC) generates foundational standards for space debris mitigation.
• Whipple shields are used to protect spacecraft from MMOD impacts.
• ISRO uses Whipple shields for Gaganyaan crew protection, validated by facilities like the gas gun at TBRL, Chandigarh.

Detailed Insights:

• Micrometeoroids originate from collisions between asteroids and comets, traveling at extremely high velocities (11 to 72 km/s).
• Orbital debris primarily comes from exploded rocket stages, satellites, accidental collisions, and anti-satellite weapon tests, with an average speed of 10 km/s.
• The Kessler Syndrome is a theoretical scenario where collisions between space debris create a cascade of further collisions, making space travel impossible.
• IADC's technical standards form the basis for space debris mitigation guidelines adopted by the UN Committee on the Peaceful Uses of Outer Space (UNCOPUOS).
• Orbital debris is concentrated in Low Earth Orbit (LEO), ranging from 200 km to 2,000 km altitude, with millions of pieces of debris, including over 128 million pieces greater than 1 mm.
• Space agencies use engineering models and software tools to determine the MMOD flux and calculate the probability of loss or failure of critical components.
• Whipple shields protect space vehicles by using a bumper to shatter incoming debris into a cloud of fragments, distributing momentum to the rear wall.
• Space agencies track objects larger than 10 cm and perform debris avoidance maneuvers to avoid potential collisions.
• Gaganyaan's MMOD protection scheme employs passive defenses like Whipple shields, validated by facilities like the gas gun at TBRL.

Key Concepts Involved:

• Micrometeoroids: Extremely small particles originating from asteroid collisions and comets, posing a threat to spacecraft.
• Orbital Debris: Human-made objects in Earth's orbit that no longer serve a purpose, also known as space junk.
• Kessler Syndrome: A theoretical scenario of cascading collisions among space debris, making space travel impossible.
• Whipple Shield: A protective shield used on spacecraft to dissipate the energy of high-velocity impacts from space debris.