The asteroid will pass the Moon at 21,200 kilometers of empty space
Desde los confines del sistema solar, un asteroide descubierto a finales de 2024 despertó por un tiempo la atención de los sistemas de defensa planetaria de la humanidad. Durante meses, la pregunta de si 2024 YR4 podría impactar la Tierra —o incluso la Luna— mantuvo a astrónomos de todo el mundo con los telescopios apuntados al cielo. Hoy, gracias a las observaciones del Telescopio Espacial James Webb, esa pregunta tiene respuesta: el asteroide pasará a 21.200 kilómetros de la Luna en 2032, sin representar amenaza alguna. Es una historia que no termina en catástrofe, sino en conocimiento.
- El descubrimiento de 2024 YR4 activó los protocolos de defensa planetaria de la NASA, generando una alarma que se extendió por medios de todo el mundo con más dramatismo del que los datos justificaban.
- Durante meses, la incertidumbre sobre su trayectoria fue real: en febrero de 2026, la probabilidad de impacto lunar llegó a estimarse en un 4,3%, una cifra pequeña pero suficiente para mantener a los científicos en alerta.
- La geometría orbital del asteroide lo hacía difícil de observar desde telescopios terrestres, lo que amenazaba con dejar abierta una ventana de duda hasta 2028 o más tarde.
- El Telescopio James Webb intervino de forma decisiva en febrero de 2026, refinando los cálculos orbitales con una precisión sin precedentes y cerrando anticipadamente esa incertidumbre.
- El resultado es concluyente: ni impacto terrestre ni lunar en 2032; el asteroide pasará a 21.200 km de la superficie lunar, y la vigilancia continúa como protocolo activo.
A finales de 2024, la NASA detectó un asteroide con una trayectoria que merecía atención. El objeto, bautizado 2024 YR4, activó los protocolos estándar de defensa planetaria y puso en marcha una red global de observación. La pregunta central era concreta: ¿podría impactar la Tierra el 22 de diciembre de 2032?
Durante meses, esa pregunta no tuvo respuesta definitiva. Las primeras estimaciones apuntaban a una posibilidad real de impacto, y la noticia circuló ampliamente. Pero a medida que se acumulaban observaciones a lo largo de 2025 y principios de 2026, la órbita del asteroide se fue definiendo con mayor claridad. Lo que emergió fue tranquilizador: la Tierra nunca estuvo en peligro serio.
La atención se desplazó entonces hacia la Luna. ¿Podría el asteroide golpear a nuestro satélite natural? Por un tiempo, esa posibilidad fue lo suficientemente plausible como para que los científicos le asignaran una probabilidad del 4,3% en febrero de 2026. No era una cifra despreciable.
Fue el Telescopio Espacial James Webb quien disipó la duda de forma definitiva. Sus observaciones de febrero de 2026 refinaron los cálculos orbitales con una precisión sin precedentes, revelando que 2024 YR4 pasará a 21.200 kilómetros de la superficie lunar —una distancia mayor que la que separa la Tierra de la Luna—. El impacto quedó completamente descartado.
Este hallazgo tiene un valor que va más allá del alivio inmediato. La geometría orbital del asteroide lo hacía difícil de observar desde tierra, y la incertidumbre podría haberse prolongado hasta 2028. Webb cerró esa ventana años antes de lo esperado. La historia de 2024 YR4 ha pasado de ser una amenaza potencial a convertirse en un ejemplo de detección exitosa: un asteroide observado, medido y comprendido a tiempo.
Late last year, NASA spotted a rocky asteroid moving through space on a trajectory that warranted attention. The discovery of 2024 YR4 triggered the agency's planetary defense protocols—the standard playbook when a celestial object might pose a threat to Earth. Since then, telescopes around the world have been trained on this rock, tracking its path with the precision that modern astronomy allows. The initial concern was straightforward: could it hit us on December 22, 2032?
For months, that question hung in the air. Early estimates suggested a genuine possibility of impact, and the story circulated widely, sometimes with more alarm than the data actually warranted. But as observations accumulated through 2025 and into 2026, the picture shifted. The asteroid's orbit became clearer, more defined, less ambiguous. What emerged from months of careful measurement was reassuring: Earth was never in serious danger from 2024 YR4.
Then attention turned to the Moon. If the asteroid wasn't going to hit us, could it strike our nearest neighbor? For a time, that seemed plausible enough that scientists assigned it a probability—4.3 percent as of February 2026. It was small, but not negligible. The Moon, after all, sits much closer to Earth's orbital path than our planet itself does. But here too, the latest data brought clarity.
In February of this year, the James Webb Space Telescope—the most powerful eye humanity has pointed at the cosmos—observed 2024 YR4 and refined its orbital calculations with unprecedented precision. What Webb revealed was that the asteroid will pass the Moon at a distance of 21,200 kilometers. That's roughly 13,200 miles of empty space between the rock and the lunar surface. For context, that's farther than the distance from Earth to the Moon itself, which orbits at about 384,400 kilometers away. The asteroid will miss entirely.
This finding matters more than it might initially seem. For much of 2025, 2024 YR4 was difficult to observe from ground-based telescopes or even from space observatories positioned near Earth. The geometry of its orbit made it a moving target in the literal sense—hard to pin down, hard to measure. That uncertainty could have persisted for years. Scientists might not have had confident answers until 2028 or later, leaving a window of doubt open far longer than necessary. Webb's capabilities closed that window early, providing the orbital precision needed to rule out impact entirely.
NASA's monitoring continues. The protocols remain in place. But the story of 2024 YR4 has moved from one of potential threat to one of successful detection and measurement. An asteroid that once warranted planetary defense alerts will pass harmlessly by, observed and understood, a small victory for the systems humanity has built to watch the sky.
Notable Quotes
The asteroid will pass at a distance of 21,200 kilometers from the Moon— NASA, based on James Webb Space Telescope observations
The Hearth Conversation Another angle on the story
When NASA first spotted this asteroid, what made them think it could actually hit Earth?
The initial orbit calculations suggested a close approach in 2032. With enough uncertainty in those early measurements, impact couldn't be ruled out. That's how the system works—you flag anything that can't be immediately dismissed.
But they downgraded it pretty quickly, didn't they?
Not quickly, actually. It took months of observation. The real shift came when they started ruling out Earth impact and had to reconsider the Moon instead. That's when you know your data is getting better—the threat moves from vague to specific.
Why did the James Webb telescope matter so much here?
It could observe the asteroid during a window when ground telescopes couldn't see it clearly. Webb gave them the precision to define the orbit well enough to know exactly where it would be in 2032. That's the difference between uncertainty and certainty.
So they basically solved the problem years early?
Exactly. Without Webb, they might have been anxious about this until 2028. Instead, they know now. The asteroid will miss by thousands of kilometers.
Does this change how NASA watches for asteroids going forward?
It validates the system. Detection works. Monitoring works. And having the right tools—like Webb—makes all the difference when you need precision.