Small asteroid to hit Earth's atmosphere today
A car-sized asteroid designated 2024 RW1 was detected only about eight hours before it entered Earth’s atmosphere over the Philippines, where it burned up harmlessly in a bright fireball. Commenters use the event to explore how often we spot incoming objects in advance, why small meteors are usually safe while 50–140 meter bodies would cause serious regional damage, and how current and upcoming survey systems (like Catalina, NEOWISE, NEO Surveyor, and Vera Rubin) will dramatically improve detection. They generally conclude that civilization-ending impacts from large asteroids are already very unlikely to be a surprise, while many more small, harmless fireballs will be routinely predicted in the near future.
Event details and immediate reactions
- A ~1 m “small car–sized” asteroid, 2024 RW1, was detected ~8 hours before atmospheric entry and burned up over the Philippines, producing a bright green fireball visible even through some cloud cover.
- This is noted as only the ninth time an asteroid was discovered before impact. Some commenters found the detection impressive; others were uneasy about the short warning.
- Video shows a larger fireball than some expected; several say they would have been alarmed without prior notice.
Detection capabilities and survey coverage
- Small objects are hard to find; detections are partly “luck,” but dedicated surveys like Catalina, Pan-STARRS, ATLAS, NEOWISE, and NASA’s Sentry system significantly improve odds.
- Discussion over whether we are limited by faintness (“photon constrained”) or by how much sky we scan; answer: both, but sky coverage for dangerous sizes is already “pretty good.”
- Future systems (Vera Rubin Observatory, NEO Surveyor) are expected to increase known asteroids roughly tenfold and greatly improve warning times.
Risk from larger asteroids
- Larger asteroids are rarer but reflect more light, so they’re typically discovered earlier and tracked years in advance.
- Several emphasize that civilization-ending impacts are extremely unlikely and that people can live without worrying about them.
- NASA guidance quoted: objects <25 m generally burn up; ~50–60 m can cause severe regional damage (e.g., Tunguska-scale); ~140 m is a common “hazardous” threshold.
Speed, visibility, and physics debates
- Faster impactors reduce warning time but are “just as visible” in principle; debate over whether survey cadence makes fast objects easier (longer image streaks) or harder to catch.
- Clarification that collision-course objects only “don’t move” in the sky very close to impact; earlier they show motion.
- Mass is the main risk driver because velocities for solar-system impactors cluster within a limited range; speed still matters but less than orders-of-magnitude mass differences.
- Quantum-mechanics jokes lead to clarification that large bodies follow classical trajectories; observation does not change impact odds in any practical sense.
Graphics, observation, and side topics
- ESA impact maps: green zones show expected breakup altitude (~100 km); red/yellow zones show hypothetical surface impact without atmosphere; the red line connects those.
- Some discuss hearing meteors (possible electromagnetic-induced sounds) and cloud cover limiting visibility.
- Side threads explore using asteroids as weapons, orbital deflection, and potential future interception capabilities.