No, it will not be asteroid strikes, supernovae blasts, and other calamities — though that is likely too. But there is ONE cataclysmic event That is DESTINED to wipe out life from the surface of the Earth and scientists have figured out when.
New Delhi: We all know that this Universe comes with an Expiry Date … a Use-By period that scientists agree cannot be completely eliminated. Annalee Newitz, a science journalist who penned the book (“Scatter, Adapt, And Remember“) on how mankind will survive another mass extinction, says that the Earth is still teeming with life and life force despite 5 successive events of mass extinctions in its history of 3.5 billion years since life evolved on the planet – since multicellular evolved. Life is resilient. The first living things on Earth appeared as far back as 4 billion years ago, according to some scientists. And surprisingly, life persisted anyway despite the fact that at that period in time our planet was still being pummeled by huge space rocks. And throughout Earth’s history, it’s seen all manner of cataclysms followed by mass extinctions that have even eliminated most species on Earth. And life has shown resilience, re-emergence, and life’s cycle keeps repeating.
Will It Be Due To An Asteroid Impact Apocalypse? Hell, No!
When a city-sized asteroid struck the Gulf of Mexico 66 million years ago, it was game over for the dinosaurs. Earth gets hit by a large asteroid roughly every 100 million years, according to NASA. However, smaller asteroid impacts do happen all the time.
Could it be ‘Death by deoxygenation’? Nopes, again!
Nearly 2.5 billion years ago, a period called the Great Oxidation Event gave us the breathable atmosphere we all now depend on. But about 450 million years ago – in an event dubbed as the Late Ordovician mass extinction, the planet saw a sudden drop in oxygen levels that lasted for several million years. Similarly, climate change is already reducing oxygen levels in our oceans, potentially killing off marine species. But that also will not wipe out ALL life on Earth.
Could a gamma-ray burst (GRB) wipe out all life? Naaaa!
GRBs are mysterious events that seem to be the most violent and energetic explosions in the cosmos — but can one be so powerful to cause a mass extinction on Earth? A GRB pointed in our direction might last just 10 seconds or so, but it could still destroy at least half Earth’s ozone in that short period of time. That could create a smog blanket over the entire Earth and would block out sunshine and kickstart a global ice age. But even that is unlikely to wipe out the ENTIRE life on Earth.
Brace yourself: Here’s WHAT WILL KILL ALL LIFE on Earth!
Whether or not any of the above devastating astronomical events happen, in about a billion years, most life on Earth will eventually die anyway due to a lack of oxygen, says the research paper. This study published in March in the journal Nature Geoscience that we mentioned above.
The researchers suggest that our oxygen-rich atmosphere is not a permanent feature of the planet. Instead, in about a billion years, solar activity will cause atmospheric oxygen to plummet back down to the level it was at before the Great Oxidation Event. To determine this, the authors combined climate models and biogeochemistry models to simulate what will happen to the atmosphere as the Sun ages and puts out more energy.
They found that, eventually, Earth reaches a point where atmospheric carbon dioxide breaks down. At that point, oxygen-producing plants and organisms that rely on photosynthesis will die out. Our planet won’t have enough lifeforms to sustain the oxygen-rich atmosphere humans and other animals require.
The precise timing of when that starts and how long it takes — the deoxygenation process could take as few as 10,000 years — depends on a broad range of factors. But, in the end, the authors say this cataclysm is an unavoidable one for the planet.
But don’t start panicking just yet. The human race — too busy though it is killing fellow humans in war and abusing/exploiting other life forms on Earth – still has another billion years to figure out other plans.
