Being an amateur astronomer enthusiast all my life, having read numerous science books about Universe origin and destiny, cosmology, physics, astronomy, not to forget a huge number of SF novels, watching SF movies all depicting glorious future of the mankind in space exploration, I am bound to admit myself a sobering truth that this is one of the grandest illusions of all. For a simple reason: the humans are not built/born for space travel, life in space or to live on another planet.
Konstantin Tsiolkovsky, the pioneer of the space flight and one of the founders of astronautics wrote about 100 years ago a famous quote, that the "Earth is the cradle of humanity, but mankind cannot stay forever in the cradle".
I would agree with the first part of the quotation but disagree with the second part. Yes, the Earth is the mankind cradle, but it will be also the mankind grave, its eternal destination, I would add.
It has been a proven fact that prolonged stay (weeks, months) in the weightlessness ambient, like on International Space Station, has serious negative impact on human health. To mention some: muscle atrophy, deteriorating bone density, vision change, overall body weakness plus mental challenges like isolation, lack of energy, and depression in a first place.
It turns out that the human beings are finely tuned for life on the Earth under its gravity force. Being exposed to a less gravity, like on the Moon or on the Mars or being on the spaceship in space has detrimental health effects. The fully fit, physically and mentally, crew on a spaceship enroute to Mars, let's say, would likely arrive as an ill and unfit/incapable for any exploration work.
The challenges of spacefaring alone are enormous, both technologically and financially, to develop a reliable space technology such as an artificial gravity and spaceship drive sustainable for life.
It would take humanity in whole, working together to deliver this. Unfortunately, history of humanity is history of confrontations not collaboration, history of wars, miseries as philosophers and historians had duly noted in the past. Further to this, the human mind (like the human body) is not ready for stars. It is pre-occupied with current affairs, irresponsible procreation thus overcrowding the planet, insatiable consumerism satisfying its endless needs, unrestricted exploitation/destruction of planet resources and creating massive pollution in turn. The mankind focus is mostly on today not on tomorrow or what will be the day after tomorrow.
In other words, humanity is digging a grave in its own cradle.

BoNe
Ottawa, May 2025.