In just weeks, a 50-meter-wide asteroid named 2011 ES4 will pass within 72,000 kilometers of Earth—about one-fifth the average Earth-Moon distance. Experts at NASA assure no impact risk, but its size and proximity earn it 'potentially hazardous' status for vigilant tracking.
Skywatchers are still thrilled by Comet NEOWISE, visible to the naked eye from sunset near the Big Dipper's legs—a rare sight, as it won't return near the Sun for 6,800 years.
NASA's spotlight now shifts to asteroid 2011 ES4, set for its closest approach on September 1 at under 72,000 kilometers. Though collision odds are negligible, its 'potentially hazardous' designation means scientists will observe it closely to gather valuable data on near-Earth objects (NEOs).
Before then, five other asteroids will safely zip by: 2002 BF25 on July 21, 2020 ND on July 24, 2020 MX3 on July 29, and 2018 PY7 and 2007 RF1 on July 31. August brings four more, all at safe distances, ahead of 2011 ES4.
Known asteroid orbits are well-mapped, but surprises occur—like last July's 100-meter rock detected just hours before grazing Earth at 70,000 km. Such events underscore the need for robust planetary defense.
NASA and ESA are leading with the DART (Double Asteroid Redirection Test) mission, targeting binary asteroid (65,803) Didymos for a trajectory deflection test in 2022. Soon, the Vera C. Rubin Observatory will scan the skies, uncovering tens of thousands of new asteroids to enhance our safeguards.
