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| the future of Earth? |
Blistering temperatures,asteroid impacts and a red giant for a Sun-and that's just a small taste of what's in store for our home planet
As the most tranquil planet our Solar System has ever known spins on its axis, seeming to lead us
through an infinite amount of days, it’s hard to imagine our Earth is going to feel the strain of a
variety of events that are set to truly put it through its paces. Yet, as it goes through the motions of
its future evolution, the planet we rely on for our survival has a trying time ahead of it. Will our
haven grow for the better, or will it become a shadow of its former self as it struggles to counteract
the chaos of the universe? You might take it for granted, but Earth is being
tested even at this very moment. Somewhere in the universe there could be a comet or asteroid
headed our way. We orbit in a corner of the cosmos containing numerous chunks of rock and ice
hurtling through the Solar System, so you’d think that, given the amount of times we’ve been buzzed
by an approaching asteroid that misses us by an astronomical hair’s breadth, our days would be
numbered. It only takes one behemoth piece of space debris to be at the same place and time as
us for disaster to strike, driving a mass extinction across the planet. After all, we know this has
happened in the past – just thinking about the fate of the dinosaurs is proof enough.
An asteroid similar to the massive chunk of rock that
wiped out the dinosaurs could one day wipe out humanity
if we don’t find ways to deflect them
Ed Lu, a former astronaut and co-founder of the B612
Foundation, is aiming for the construction of the Sentinel
Space Telescope that will alert Earth to potentially
dangerous asteroids
“ The only thing so far preventing a
catastrophe from a city-killer-sized
asteroid has been blind luck”
-Ed Lu, B612 Foundation
Around 65 million years ago an asteroid belted our world with such a force
that a good portion of life was thrown into disarray as the land shook and great tsunamis took a hold of the world. The 180 kilometre- (112 mile-) wide Chicxulub crater in the Gulf of
Mexico, along with bones and fossils of the final resting places of ancient life, marked the beginning
of the Earth’s Cenozoic Era, a period that continues to this day. Though we’ve been lucky since, we’re always in the potential firing line. “While most large asteroids with the potential
to destroy an entire country or continent have been detected, less than 10,000 of over a million
dangerous asteroids with the potential to destroy a major metropolitan area have been found by all
existing space or terrestrially operated observatories,” says Ed Lu, a former US Shuttle and Soyuz astronaut. Lu, as part of his organisation the B612 Foundation, aims to build the Sentinel Space Telescope, an Earthorbiting sentry that would keep a watchful telescopic
eye for any potential dangers. Sentinel would raise an early alarm for any dangerous asteroids heading our way. The idea is that finding these threats in advance of them arriving will gift us enough time to deflect anything looking to snuff us out with a single blow. “Because we don’t know where or when the next major impact will occur, the only thing so far preventing a catastrophe from a city-killer-sized asteroid has been blind luck,” adds Lu. It's estimated that some 1.4 million years from now we’re going to need to thwart comets raining on the inner Solar System from the Oort Cloud, a halo of icy bodies in orbit at the very edge of our celestial neighbourhood. The possible culprit responsible for the future battering Earth could receive is Gliese 710 – a main sequence orange dwarf that will approach the Sun as close as one light year before swinging away again, disrupting the Oort Cloud's structure along the way. Lu has highlighted an important point with his venture – whether it’s asteroids or the uncomfortable proximity of comets, we need to ensure that the likes of the current NEOWISE telescope, as well as the future Sentinel, assist us in keeping our world out of harm’s way. However, that’s only one hurdle that we have to overcome as thousands of years turn into millions. Provided we can deflect these murderous travellers, we will get a bit of a reprieve from Earth’s ultimate fate. From the surface of the Earth, thousands of years in the future, we will be able to see some significant changes in the night sky. The small red dwarf star astronomers have dubbed Ross 248, which rests in the constellation Andromeda some ten light years away, will move in closer to our Solar System to make it our nearest star ahead of Proxima Centauri, a current 4.24 light years away. It’s thought that the pint-sized Ross 248 is likely to reach a minimum distance of roughly three light years from us, in around 33,000 years from now. However, it won’t be this way forever. Once again the system Alpha Centauri and then Gliese 445 will be made the nearest stars around 8,000 years after Ross 248 has decided to loop away from our planetary system. In fact, the night sky will change over time with several stars taking it in turns to move closer to our Solar System. If this weren’t enough, we can also expect some major activity beneath our very feet. The continents that we live on will be unpicked and sandwich onto others, jostling in such a way that a new supercontinent will be formed 250 million years from now. Some experts call this future landmass Pangaea Proxima, while others have put forward other supercontinent contenders such as Amasia, which would see Asia and North America joining together. Another possibility, Novopangaea, has been predicted by the University of Cambridge’s Roy Livermore and would see the closure of the Pacific as Australia docks with eastern Asia and Antarctica moves further north. The general consensus is that Pangea Proxima, also referred to as Pangaea Ultima, could be the leading setup for the Earth’s future landmass. “It’s all pretty much fantasy to start with, but it’s a fun
exercise to think about what might happen,” says
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