Small debris orbiting Earth pose threats to space assets

Small debris orbiting Earth pose threats to space assets

Subject : Science and Technology

Section: Space technology

Context: On March 7, 2023, the Indian Space Research Organisation (ISRO) successfully carried out a controlled re-entry for the decommissionedMeghaTropiques1(MT1). The satellite, launched more than a decade ago, was designed to study clouds in the tropical regions of the world. It was expected to make final impact in the Pacific Ocean. ISRO said the satellite was brought down as a part of its commitment to reduce space debris, especially in the much crowded Low Earth Orbit (LEO).

Space debris

• Space junk is any piece of machinery or debris left by humans in space—principally in Earth orbit.
• These include dead satellites, fragments of rocket bodies and spacecraft etc.
• Currently, an estimated 20,000 objects—including satellites and space debris—are crowding low-Earth orbit.

What causes space junk?

• Unoperational / Expired / Exploded satellites, rocket parts or spacecrafts
• Anti-satellite tests that incapacitates or destroys satellites for strategic or tactical purposes (like Mission Shakti conducted by DRDO, China’s 2007 ASAT test,etc.)
• Rare collision between two spacecrafts
• Mega-constellations of satellites planned by companies such as SpaceX ‘s Starlinkprpject

Kessler syndrome

• This is an idea proposed by NASA scientist Donald Kessler in 1978.
• The Kessler syndrome is a scenario in which the density of objects in Low Earth Orbit (LEO) is high enough that collisions between objects could cause a cascade that increases the likelihood of further collisions.

ISRO’s Efforts

• ‘Project NETRA’ – It is an early warning system in space to detect debris and other hazards to Indian satellites.
• Only the US, Russia and Europe have similar facilities in place to track space objects and share collision warnings.