Yes, in the same way that affordable flying cars are science fiction. The technology is known in theory; we just have (possibly insurmountable) political, financial, and legal hurdles to overcome before it will become possible.

Not really comparable. Flying cars are not technological fiction, they're just called helicopters, it's just that from a economic/ecology POV they make no sense.

Space travel between worlds is SF.

It miht be science fiction but before the space race traveling to the moon was science fiction too. Yet we did not only travel to the moon but actually walk on it.

I don't have any doubts that at some point humanity will find a way to do interstellar travel. Though I doubt it will happen in our lifetime

But we have sent probes to other worlds? What is science fiction about this?

A manned mission to Mars is entirely feasible with current technology. In fact I'd argue it'd have been feasible with 1980s technology, it was simply costly. If we (we as in humankind) wanted, we could have a base on Mars for some time now.

Who is to say what our capabilities will be in 50 years? In 100 years?

A manned mission to another solar system is going to be very-very difficult, we'd need generational space ship/habitats. Note that difficult is not the same as impossible. Such a ship could be feasibly constructed with modern day technology, but it would be enormously costly so there was no motivation to do it.

I'd agree with your point that a mission to another galaxy is basically unimaginable with technology we can realistically theorize about today. We'd need extremely exotic physics which are unlikely to be doable ever.

> But we have sent probes to other worlds? What is science fiction about this?

Probes aren't space travel for humans.

> A manned mission to Mars is entirely feasible with current technology.

As no manned missions to Mars have ever proven this conjecture, it is still entirely speculation on your part.

> A manned mission to another solar system is going to be very-very difficult, we'd need generational space ship/habitats. Note that difficult is not the same as impossible.

No, it is impossible. Humans cannot survive in space that long. Never have, currently can't, and there's no precedent to assume it ever becomes possible. Pure speculation on your part.

>As no manned missions to Mars have ever proven this conjecture, it is still entirely speculation on your part.

But we do have manned missions to other celestial bodies, and we have sent and landed probes on Mars. I'm confused as to how a manned mission to Mars is "entirely speculation".

>no precedent to assume it ever becomes possible

This isn't a qualifier for what is possible. We knew it was possible to go to the moon before there was precedent. If anything, you calling it impossible is pure speculation. OP is right, difficult is not the same as impossible.

Manned, i.e. containing people (men).

um, yes?

Agree that interstellar travel is impossible with current tech.

But based on what I know, I don't see any reason to believe a manned mission to Mars is impossible with current technology.

Do you have specific reasons we can't, or examples of technological gaps?

- One year in weightlessness will almost disable someone and give him blindness, rapid bone loss, cachexia, cardiovascular problems, and sometimes immune diseases.

- One year enduring radiation sickness.

- artificial gravity through rotation

- various strategies to block incoming cosmic rays: https://en.m.wikipedia.org/wiki/Effects_of_ionizing_radiatio.... In particular, hydrogen-rich plastics.

Sometimes Science Fiction is confused with Fantasy, but as far as it means "fiction about things that are scientifically possible but don't exist" I'd say traveling to other planets is SF. Traveling to other worlds (ie. interstellar) is fantasy. And living on other planets (terraforming) or outer space is somewhere in the middle: technically not impossible but very undesirable without major future tech.

Fans of space colonization are encouraged to read: a City on Mars by Weinersmiths, https://www.acityonmars.com/

There are people living in space stations right now? Are you saying rockets are fake or do you mean that we don't have any permanent habitats on other planets?

E.g. https://whoisinspace.com/

They are not living in space, they are temporary visitors on an unstable structure that requires constant resupply from Earth, absent of which they will all die and the structure falls back to Earth and is destroyed. Even with indefinite resupply, astronauts have to return to Earth for health reasons, because our bodies did not evolve / were not designed for space. Astronauts get irradiated and lose reproductive fertility.

I can't really find where your line for "space travel" is. Humans on earth need resupply from other parts of earth, the bases on Antarctica are about equally as unhospitable towards humans, not to mention cruise ships where some people live aboard for years at a time.

Heck, my own house is an unsustainable habitat that requires constant resupply.

We are lose reproductive fertility on earth too.

Space travel is not science fiction. Living somewhere other than Earth permanently is science fiction.

Science fiction often becomes reality. There are companies, governments, and NGOs working on extraterrestrial habitation as we discuss this. While it will be expensive and make many rather unhappy, it will likely happen… assuming that humankind doesn’t annihilate itself first.