One of the facts which I had observed over the decades, was that in my youth, the concept of manned space travel and exploration was followed at first with keen interest, but that interest had waned at some point in time, and that the idea had become unfashionable.
Unmanned space exploration, on the other hand, remains fashionable, partly because it generates more-obvious benefits in the short term, but also because it tends to be more affordable.
But I honestly think that what is happening right now, given that an Earth-Sized Exoplanet has been found orbiting Proxima Centauri – the closest star to our own solar system – is that some, slow revival of the idea of manned space exploration is in the works. I think that even though somebody has just spent decades, effectively shutting down this concept, it is going to be reawakened. Beyond Mars, eventually People are going to want to travel to The Outer Solar System, and eventually to other stars.
It is one of the ways in which Human Nature is predictable, however disappointing it has been in the past.
Proxima Centauri has a known planet.
Note: However far-flung the idea might seem according to Engineering Realities, it is actually plausible, that mankind might be able to reach Proxima one day. It will be more difficult than Mars, but still possible, especially since doing so does not actually require that anything travel faster than the speed of light.
But if this is to be taken seriously, it also provides fuel for the recent efforts, to develop something akin to ‘a tractor beam’. Travel at say, 1/2 the speed of light, risks becoming ‘a nuclear sandblasting exercise’, due to cosmic dust, unless something is done to sweep dust particles out of the path of a hypothetical spacecraft. And as it stands, we could design a spacecraft simply to possess a powerful laser pointing forward along its path. But what this would due to dust particles, at most, is to accelerate them down the path our craft would already be taking. So, an impact with a cosmic dust-particle might be delayed by one microsecond, before it emits gamma-rays, etc. Such an impact would have nuclear-range kinetic energies.
If any possibilities exist, to make that particle accelerate along a vector 90° away from the path of the spacecraft, it would be highly useful…
Further, the actual amount of time-dilation which would follow from traveling at 1/2 the speed of light, is 15.470054% (rounded up).