To boldly go where no man has gone before

Many associate survival of our species with humanity becoming a interplanetary civilization. It’s important to prepare ourselves for an event that might one day force us to leave our home planet. In more distant future we might have to leave our solar system. Will we ever become an intergalactic civilization like we already are in science-fiction? What’s the hardest obstacle to overcome?

Fraser Cain (publisher at, co-host of Astronomy Cast)


The hardest obstacle to overcome is the weightless environment of space itself. Humans evolved in Earth’s gravity, and without it, our bones soften, our muscles atrophy, and our bodies suffer. Until we can develop some kind of artificial gravity environment, like a rotating space station, space travel will be lethal for any length of time. We need to first learn to just live and survive in space before we have any hope of reaching out to another star system.

Andrew Rader (SpaceX engineer, MIT PhD, author)


If we survive for the next 100 years, I think we will become an interstellar civilization (although maybe not for several hundred years – the first step is to expand into our solar system first). The greatest challenges are in rough order of difficulty starting with the most challenging: I) Surviving long enough to reach the stars (avoiding disaster on our planet, whether created by humans or something external); II) The will to expand beyond Earth (will we even choose to do so, or will we for example, transcend into AI); III) The vast distances involved and the technological challenges involved. These include the velocity you need to travel and/or time it would take to get to another star, and the energy you would need to be able to produce for an exceedingly long time at a great distance from any light or heat from the Sun (even our best nuclear technology can’t currently do this). It’s a problem of distance, time, and energy. Here’s a links to my videos about it.


Human colonization:

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)


Emigrating beyond Earth is not a difficult task from a technological perspective. The current challenges are more centered on budgets rather than technology or human will. The most difficult challenge of interplanetary travel, in my opinion, is the challenge of humanity. Humans, today, are in the brink of destroying ourselves and our planet as well. The human population is increasing at an exponential pace while Earthly resources are diminishing at equal speed. Humans, eventually, will nonetheless have to travel beyond earth to survive as a species. We must, however, overcome the most difficult obstacle we conveniently ignore: the will to get along with other humans.

Pamela Gay (assistant research professor at Southern Illinois University, writer, co-host of Astronomy Cast)


Our science fiction stories show humanity escaping out to the stars, but our more terrestrial reality seems determined to keep us grounded. Two major problems currently face us. The first, quite simply, is resources. Human space exploration is a rich nation’s possibility, and as our global economy flattens, it is becoming harder to imagine any government-driven effort to colonize other worlds and other solar systems. At the same time, it’s impossible to predict what commercial space will make possible, and the extreme wealth of an elite few may be able to fill in gaps left by governments. While money is a current problem that has the potential to go away, the second problem is more likely to stay. That problem is human frailty. We are a race that can die from environmental extremes and disease. We periodically wage war, and we release toxins into our environment through our accidents and ignorance. The real question is, will we stay alive long enough to overcome money?

Ciro Villa (technologist, application developer, STEM communicator)


Be it for natural or man-made causes, there are a variety of possible future scenarios that we earthlings could face that could bring about the end of humanity or even life in its entirety here on Earth. This is why it is important to give serious consideration to plans for us to become a space faring civilization. Although we have a long way to go to arrive at the necessary level of technology and for us to be able to overcome a number of practical obstacles to make this feasible, it is important to start working toward this goal, this way at least our future generations can hope for the continuation of our species by embarking on “space lifeboats” toward new galactic shores. This is not going to be easy and it is going to take time and effort. We are now just making our first “baby steps” toward understanding how the human body reacts to hostile space environments and the lack of gravity and questions about our ability to withstand space environments are just now attempted to be answered with the hard work of our astronauts on the International Space Station. Probably one of the hardest obstacle to overcome is going to be having the ability to take down the barrier of skepticism of large portions of the public as a whole and raise realistic and not alarmist awareness that we live on a very fragile planet and that it is important to build contingency plans to leave it if we want the continuation of our species. Of course we hope that we will be able to achieve this goal before it will be too late.

Paul Carr (Space Systems engineer at NASA, podcaster, blogger, investigator)


I tend to be skeptical of top-down views of the human future, and the more our species is spread out into the solar system, the more it will diverge, with separate populations each pursuing their own interests. From, this is an optimistic view. The kings and battles view of history has always been something of a delusion, and I think in the future it will become clear, with hopefully no kings and many fewer battles. So, I think the simple-minded notion of a colossal public works project sending great arks full of people in uniform to seed humanity among other worlds is not only unlikely, it is undesirable and likely to fail. Someone with the power to make that happen has too much power. However, I do believe that as mastery of space travel, energy and information compounds, our wealth will grow to the point that the project of embarking with one’s friends and families to the stars is a choice many will have. How this will be accomplished I don’t know, and neither does anyone else, just as the hunter gatherers just before the neolithic revolution could not possibly see what their world was about to become. It is only an approximate result, but Daniel Cartin estimated that the range needed from a starship in order to establish a network of colonies in the local solar neighborhood was about 10 light years. That’s a long distance from the human perspective, but is a cosmic stone’s throw, and when humans can live for hundreds of years and casually command petawatts of power, it will not be a daunting sea to cross. By then, we may not even need to send biological bodies – just beam our minds ahead at the speed of light after the ship arrives at a suitable destination. It would of course, take millions of years to colonize even part of the galaxy, and such a diaspora could easily lose steam after a while. Still there is the chance it will continue until we either collide the current residents or fill up the available resources. Of course, by “we” I mean descendants of humans, but they will be fragmented into at least as many many societies as solar systems they occupy. There will be no emperor. How we go from there to an intergalactic society I have no idea. Crossing ten, or even a hundred light years is nothing compared to crossing millions of light years. Each of is free to imagine their own scenario, but I have no idea how it could happen.