NASA Details ISS Emergency Amid Russian Satellite Debris Threat

 “We’re running against the clock here,” Tiago Soares, the lead engineer of the Clean Space office at ESA, warned, as yet another incident of space junk led the International Space Station to operate in emergency mode. Recently, NASA reported that the demise of a defunct Russian satellite, Cosmos 2221, produced enough space debris that shelter-in-place measures were required.

This incident happened as the station was transitioning over the Southern Hemisphere. Mission control, together with the U.S. Space Command’s 18th Space Defense Squadron, was able to identify more than 100 pieces of trackable space junk from the sudden break-up of Cosmos 2221. Due to the close proximity of this space junk’s path to that of the ISS, the ISS astronauts quickly entered their emergency ‘lifeboats,’ SpaceX’s ‘Crew Dragon’ and the Soyuz, as a precautionary measure.

Fragmentation events like that of Cosmos 2221 serve as perfect models of fragmentation events that involve high energies. Fragmentations may be caused by fuel explosion, structural failures, or hypervelocity collisions with other pieces of space junk. Fragmentation pieces will all move apart, thus heightening the threat levels of nearby satellites. According to the Space Force, fragmentation events can be distinguished from anomalous low-speed fragmentations in that they generate clouds of debris extending hundreds of kilometers in altitude. Across its orbit, the 18th Space Defense Squadron relies upon the U.S. Space Surveillance Network for tracking its debris, which includes phased-array radar systems such as AN/FPS-85, optical sensors such as GEODSS, and the Space Fence radar facility situated in Marshall Islands. These sensors give position information on more than 45,000 cataloged pieces, although pieces as low as millions may pose hazards despite being untrackable.

ISS has witnessed such dangers in the past. In June, astronauts had to take shelter in different capsules, such as Boeing’s Starliner, due to the breakup of a satellite. Such precautions cause disturbances, as scientific work is halted, regular activities are postponed, along with increasing stress for the astronauts with every such incident. Such events of taking shelter are increasing as low-Earth orbit witnesses more congestion.

That congestion is approaching thresholds described by the Kessler Syndrome a cascading chain reaction in which collisions generate debris that in turn causes more collisions. Experts such as NASA’s Mark Matney view incidents like the 2009 Iridium–Cosmos collision, which produced over 2,000 large debris pieces, as early moves in this long-term process. At present, low-Earth orbit hosts over 14,000 satellites and an estimated 120 million debris fragments, with mega-constellations like Starlink projected to expand to tens of thousands of spacecraft.

Orbital modeling with Orbital Capacity Assessment Tool from MIT, along with the use of the Debris Environment Long Term Analysis computer program developed by ESA, clearly illustrates that orbital debris may increase exponentially within some ranges of orbit. At ISS’s ~400 km orbit, atmospheric drag facilitates removal of such space junk within a few years, but beyond altitudes of 800 km, the pieces may remain intact for centuries. Such pieces, as in the case of Cosmos 2221, pose dangers within higher orbits.

modeling studies on the dynamics of space debris, such as the differentiated equation models, highlight the importance of effective active removal. These studies show that if much is not done to remove space debris, space congestion, being the occurrence of at least one collision per year between a working space mission and space debris, will be realized as early as the year 2200. Doubling the efficiency rate of removal will provide much the same stabilization as reducing the deployment rate of new missions by a factor of four.

Compared with defunct satellites that pose dangers, active removal technologies, such as ESA’s space program called ClearSpace-1, target the removal of high-risk satellites through grapple, with the objective of deorbiting them before they break apart. Although some satellites will be designed with the capability for removal, adding such technology to older satellites that pose risks, such as Envisat, poses technological difficulties. An additional example that illustrates the importance of cohesive international regulations on space debris mitigation is the Cosmos 2221 incident.

Existing rules mandated by the Interagency Space Debris Coordination Committee address deorbiting satellites within 25 years of the completion of their desired mission, on-orbit explosions, as well as the responsible disposal of operational space debris. However, the compliance rates remain under 50 percent, with neither punishment nor penalty. Experts urge the use of “gatekeeper” launch nations. Currently, the safe use of orbit relies on careful monitoring, quick crew response measures, as well as gradual improvements in the mitigation of space junk.

Obviously, the ISS crew’s quick response in taking shelter measures such as donning suits, starting capsule systems, and waiting for authorization shows that emergency preparedness is well established. However, as Soares states, Without removal capabilities, every subsequent breakup reduces the operational window for spaceflight.