Apophis's 2029 Earth Flyby
The upcoming encounter will bring the asteroid closer than many satellites, making it a rare opportunity for both planetary defense and orbital debris research. Researchers at Italy's National Research Council (CNR) ran simulations of asteroid 99942 Apophis's close pass by Earth, scheduled for April 13, 2029. Their models reveal a slight yet nonzero chance that Apophis could strike debris in high orbital bands. While such a hit would pose no danger to Earth, it might carve out an impact crater and kick up a dust cloud, potentially disrupting the RAMSES and OSIRIS-APEX spacecraft missions.
Measuring roughly 370 meters across, Apophis is due to swoop past Earth at a distance under 32,000 kilometers—well inside the orbits of many operational satellites. Despite that, astronomical calculations indicate the asteroid will not strike our planet. The research, published in The Planetary Science Journal, used computer simulations to assess whether Apophis might encounter fragments or tiny objects circling at geosynchronous and geostationary altitudes near 36,000 kilometers.
The Danger Posed by Orbital Debris
According to the team—among them physicist Giulia Schettino and astrodynamicist Alessandro Rossi—an impact would not shift Apophis's trajectory or put Earth in peril. But a relatively tiny piece of junk could still produce a crater and throw up enough dust to interfere with ESA's RAMSES and NASA's OSIRIS-APEX missions, they stressed.
There is no concern about Kessler syndrome here, the researchers note, since the density of space junk at roughly 36,000 kilometers is lower than in low Earth orbit. Even so, they call for a closer look at the population of tiny debris in high-altitude regions. Upcoming telescopes in the EU's space surveillance network are expected to provide a clearer picture of the near-Earth environment prior to Apophis's approach.
Studying close approaches like Apophis's flyby serves a dual purpose: safeguarding Earth and deepening our grasp of orbital dynamics. Heightened awareness of unlikely but plausible hazards can drive advances in tracking technology and debris management, helping protect future missions from potentially disastrous encounters.
As Apophis approaches its close encounter with Earth in 2029, it presents a unique opportunity to study its trajectory and the surrounding space environment. For those interested in the specifics of this upcoming pass, including its proximity to our planet, further details can be found in our article on the asteroid's distance from Earth.