The planet itself would remain intact. Just empty of the kind of life that needs to breathe.
En los confines del tiempo geológico, científicos de la NASA y la Universidad de Toho han trazado el horizonte de la vida en la Tierra: aproximadamente mil millones de años antes de que el envejecimiento del Sol despoje a la atmósfera del oxígeno que sostiene la existencia compleja. Es una cifra que tranquiliza y perturba a la vez, pues recuerda que incluso los mundos habitables tienen fecha de caducidad, y que la pregunta sobre el destino de la humanidad ha dejado de ser solo filosófica para convertirse en un problema de ingeniería.
- Unas 400,000 simulaciones computacionales revelan que la Tierra tiene aproximadamente mil millones de años de habitabilidad restante antes de que el oxígeno desaparezca de su atmósfera.
- El verdadero sobresalto no es el fin lejano, sino el horizonte más cercano: en apenas 250 millones de años, el calor extremo y la actividad volcánica podrían hacer la superficie insoportable para los mamíferos.
- Asteroides, erupciones masivas y cambios geológicos impredecibles podrían acelerar cualquiera de estos plazos, convirtiendo el futuro en una ecuación con demasiadas variables.
- La respuesta institucional ya está en marcha: la NASA y otras agencias exploran Marte y exoplanetas como destinos alternativos, transformando la supervivencia a largo plazo en una meta de ingeniería espacial.
- Por ahora, la Tierra permanece segura durante lapsos que superan con creces toda la historia humana registrada, pero el reloj planetario, aunque lento, no se detiene.
Científicos de la NASA y la Universidad japonesa de Toho ejecutaron cerca de 400,000 simulaciones computacionales para responder una pregunta que parece absurda hasta que se comprende su urgencia: ¿cuánto tiempo más puede la Tierra sostener la vida? La respuesta es aproximadamente mil millones de años. A partir de ese punto, el envejecimiento del Sol desencadenará cambios atmosféricos que irán eliminando el oxígeno de forma gradual, en una escala de tiempo geológico que hace imposible la supervivencia de humanos, animales y plantas. Solo las bacterias anaerobias podrían persistir en un planeta que seguiría girando alrededor del Sol, pero vacío de todo lo que hoy respira.
Sin embargo, ese horizonte lejano no es necesariamente el más urgente. Investigadores de la Universidad de Bristol advierten que en apenas 250 millones de años —un plazo considerablemente más cercano— el calor extremo podría volver inhabitable gran parte de la superficie terrestre para los mamíferos. Erupciones volcánicas, impactos de asteroides y transformaciones geológicas podrían acortar aún más cualquier estimación. El futuro de la vida en la Tierra, en definitiva, depende de más factores que el simple envejecimiento de nuestra estrella.
Esta incertidumbre ha impulsado a agencias espaciales como la NASA a explorar Marte y buscar exoplanetas que pudieran albergar asentamientos humanos en el futuro. La conversación sobre la supervivencia a largo plazo de la especie ha migrado del terreno filosófico al de la ingeniería. Por ahora, la Tierra permanece segura durante cientos de millones de años, un lapso que eclipsa toda la historia registrada de la humanidad. El reloj del planeta avanza, pero lo hace con una lentitud que deja el destino de los próximos siglos completamente en manos humanas.
Scientists working with NASA and Japan's Toho University have run roughly 400,000 computer simulations to answer a question that sounds absurd until you realize it's not: how much longer can Earth support life? The answer, according to their models, is about a billion years. After that, the planet enters a slow, irreversible decline that would make survival impossible for nearly everything alive today.
The mechanism is straightforward, if distant. As the Sun ages, it will trigger changes in Earth's atmosphere that gradually strip away oxygen. Not all at once—this is a process measured in geological time, unfolding across hundreds of millions of years. But eventually, oxygen levels will fall below the threshold that complex life requires. Humans, animals, plants: all would vanish. Bacteria that thrive without oxygen might persist, but the world as we know it would be gone. The planet itself would remain intact, still orbiting the Sun, still solid beneath its feet. Just empty of the kind of life that needs to breathe.
This timeline sounds reassuring when you consider that human civilization has existed for only a few thousand years. A billion years is a span so vast it defeats intuition. Yet the research also carries a quiet caveat: oxygen depletion may not be the first threat. Other scientists, working at the University of Bristol, have modeled a different scenario. They suggest that within 250 million years—a much nearer horizon—Earth could become so hot that mammals would struggle to survive across much of the planet's surface. Volcanic eruptions, asteroid impacts, and shifts in the planet's geology could all accelerate the timeline further. The future, in other words, depends on more than just the Sun's slow aging.
This uncertainty has not stopped humanity from planning ahead. Space agencies including NASA are actively exploring Mars and searching for exoplanets that might one day harbor human settlement. The logic is simple: if Earth has an expiration date, even one a billion years away, the species that evolved here might need somewhere else to go. Technological advancement continues to reshape what seems possible, and the conversation about humanity's long-term survival has shifted from philosophy to engineering.
For now, the reassurance holds. Earth will remain habitable for hundreds of millions of years—a span that dwarfs every moment of recorded history, every empire, every war, every dream humans have yet dreamed. The planet's clock is running, but it is running slowly. What happens in the next thousand years, or the next million, remains entirely in human hands.
Citas Notables
Scientists believe this represents an inevitable evolution over an extremely long timescale, not an immediate threat to humanity— Research team (NASA and Toho University)
Multiple factors beyond oxygen loss—including extreme climate change, volcanic eruptions, and asteroid impacts—could threaten habitability much sooner— University of Bristol researchers
La Conversación del Hearth Otra perspectiva de la historia
Why run 400,000 simulations instead of just one or two? What does that volume of modeling actually tell you?
Each simulation is a slightly different version of the future—different starting conditions, different variables weighted differently. You need that many to see which outcomes are robust, which ones hold true across the range of uncertainty. It's not about getting the perfect answer. It's about understanding the boundaries of what's possible.
So when they say a billion years, that's not a hard deadline. It's a middle estimate.
Exactly. It's the point where the models converge on a problem becoming unavoidable. But the range around it is enormous. And that's before you factor in the other threats—the volcanic eruptions, the asteroid strikes, the climate shifts that could arrive much sooner.
The Bristol study mentions 250 million years for extreme heat. That's five times closer than the oxygen scenario. Why isn't that getting more attention?
Because it's harder to visualize. Oxygen depletion is a clean story—the Sun ages, the atmosphere changes, life ends. Heat is messier. It depends on feedback loops, on how the carbon cycle evolves, on things we're still learning. And honestly, 250 million years still feels like forever to most people.
Does knowing this change how we should act now?
It reframes the conversation. We're not racing against a billion-year clock. We're racing against much nearer deadlines we've created ourselves—climate change, biodiversity loss, resource depletion. The long-term science is almost a permission slip to focus on what's actually urgent.
And the Mars exploration, the search for exoplanets—is that serious preparation or just hedging?
Both. It's serious in the sense that it's real work by serious people. But it's also honest about uncertainty. We don't know if we'll ever need to leave. We just know that having options is better than having none.