[exq]

Mars colonization doesn't make much sense, but building O'Neill Cylinders when humanity runs out of space or energy on Earth might.

>interstellar travel makes no sense

For vacation or finding new spices to sell, no, but if you've exhausted all the matter in the solar system or humanity outlives useful solar output from the sun and fusion energy is still +20 years away, there isn't really a choice.

The time it takes for interstellar travel doesn't make sense on human time scales, but people still plant trees knowing they will not live to sit under their shade.

[HeyLaughingBoy]

> people still plant trees knowing they will not live to sit under their shade

Stuff like this really gives me faith in humanity amidst the insanity I see in the news.

I've been watching a "volunteer" oak sapling grow for the last few years and I'm trying to work around it so I don't have to cut it down. I may very well be dead before it provides appreciable shade, but it's nice knowing that it's there.

On the other hand, when my now 14-year-old was three, he stuck a cast-off bit of a branch (I think it's a basswood?) into the ground outside the house and declared it as his tree and watered it faithfully for a few days before losing interest. That "branch" now towers over the house and shades a room that used to get pretty hot in the afternoon. If I had any idea that it would actually take root and grow, I'd have moved it farther away from the house.

I like trees. I've planted a few using the County's native sapling program and it's been nice watching them grow over the last 15 years.

[littlestymaar]

> Mars colonization doesn't make much sense, but building O'Neill Cylinders when humanity runs out of space or energy on Earth might.

Space on earth isn't going to run out anytime soon (as I said colonizing Siberia and Antarctica is much more approachable, and there's the oceans too!) especially since the world population is plateauing!

> but if you've exhausted all the matter in the solar system or humanity outlives useful solar output from the sun and fusion energy is still +20 years away

That “if” really feels like “I'll need a second hat if I grow a second head in the night”.

> The time it takes for interstellar travel doesn't make sense on human time scales, but people still plant trees knowing they will not live to sit under their shade.

That's a good analogy, because individuals do, but for-profits mostly plant trees with short lifetime and quick return on investment. And you're not going to fund space travel with individuals' money…