Whenever humanity is looking back in time one leitmotif comes up as a reminder that can best be described as watch the sky!
Therefore, quite a lot has been speculated about cataclysmic events in the distant past and indeed, at the end of the last ice age about 12,800 years ago, also known as the Younger Dryas impact hypothesis, there could be numerous devastating events, like comets hitting earth burning the lands and burying ancient civilizations.
It is also said, that the expiring Maya Calendar acted as a device predicting such an ever-occurring cataclysm within a window of roughly 80 years, ending in 2040.
Besides the fact that humanity is currently driving itself obsolete in a way that even celebrated physicist Stephen Hawking asserted that we have to make an expedition to find a new earth, colonization of other planets might be one way to rescue ourselves from total annihilation.
You could also follow Matthew McConaughey pondering in Interstellar:
Mankind was born on Earth. It was never meant to die here … We've always defined ourselves by the ability to overcome the impossible. And we count these moments. These moments when we dare to aim higher, to break barriers, to reach for the stars, to make the unknown known. We count these moments as our proudest achievements. But we lost all that. Or perhaps we've just forgotten that we are still pioneers. And we've barely begun. And that our greatest accomplishments cannot be behind us, because our destiny lies above us.
In a way, that’s exactly what lies before us, but in order to break yet another barrier, we first need to find innovative solutions and ways to explore the stars.
In a paper published only weeks ago, astrophysicist René Heller from the Max Planck Institute for Solar System Research in Göttingen, Germany proposed just that: new means of interstellar travel by accelerating light-weight space ships via laser or solar radiation to a significant fraction of the speed of light in combination with gravitational assistance. In other words, Heller is looking for the quickest route instead of the shortest distance by using light from stars to power ships. The brighter a given star, the faster we could travel.
The team from Germany calls this concept: the photogravitational assist. As always, the scientist applied the right math and ended up with pretty interesting calculations on the amount of time needed to reach certain destinations in outer space. According to Heller, distant stars, that are far brighter can be reached faster, e.g.: Sirius is the one humanity might be able to reach before any other star, even the ones from the Alpha Centauri system. Sirius is about 18 times brighter and a ship using the photogravitational assist could be there by 2086. That’s a whole lifetime faster that reaching Proxima Centauri in the mid-22nd century.
On an interesting side note, even the ancient Egyptians believed that their most beloved Goddess - Isis - was the Soul of the Star Sirius. Maybe there is an unknown connection attracting us to this particular place.
Anyway, here may be other possibilities to get there with light sails, but they simply do not account for the gravitational effects associated with the work of Heller’s team. In a recent interview, Heller also proposed what’s needed to build a light sail by summarizing that
“We need a very light, solid, temperature-resistant, and highly reflective sail material that can span an area of several hundred meters squared [adding that] If this works out, then humanity can really go interstellar.”
Actually, our planet is already trying to expel us, literally telling us to leave and we better prepare for anything by remembering the past and quasi-working on our future and thanks to these scientists we are now more than just one small step closer to reaching the stars and surviving as a species.