NASA scientists have explained why aliens still haven't come to visit us yet.
You'd think that with all their UFOs and time-travelling capabilities that, at least, one alien would pay us a short visit.
A quick cup of tea and a few biscuits - then off you go.
Anyway, it seems that a group of NASA scientists have theorised that aliens haven't come to visit us yet, because they already wiped themselves out, which isn't ideal.
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Their reasoning is that intelligent societies tend to wipe themselves out, one at a time, and the human race could be next.
The report - Avoiding The Great Filter: Extra-terrestrial Life And Humanity's Future In The Universe - was authored by Jonathan Jiang, Philip Rosen, Kelly Lu, Kristen Fahy, and Piotr Obacz.
"We postulate that an existential disaster may lay in wait as our society advances exponentially towards space exploration…" the report said.
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"The Great Filter has the potential to eradicate life as we know it, especially as our rate of progress correlates directly to the severity of our fall.
"This indicates a necessary period of introspection, followed by appropriate refinements to properly approach our predicament, and addressing the challenges and methods in which we may be able to mitigate risk to mankind and the nearly nine million other species on Earth."
With regards to alien life, the report concludes: "In the perspective of global behaviour, the discovery of a planet-rich Universe has rendered less a question of whether aliens exist, but rather in the occurrence that they (statistically, at least) likely do, and are we in a sufficiently stable position to receive such news.
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"But when it comes to foundational questions, the former does present interesting inquiry.
"If extraterrestrial intelligence does exist, humanity must self-improve on nearly all accounts to meet and even surpass such others.
"On the flip side, if intelligent life does not appear and perhaps never was, we have some other more philosophical difficulties to juggle – but no less daunting.
"Our lives are not expendable. We have been treating casualties as casual, nukes as necessary, and large-scale death as inevitable events.
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"Life - human life, the lives of our delicate biomes and the millions of species which inhabit it - is unique and so incalculably precious.
"Carelessness leading to failure is not an option.
"We are the only ones who can help ourselves; there should be no expectation of mentors or saviours to step down from the sky on our behalf."