If by “we” you mean humans, we only “have” one planet. And it’s habitable for now.
Aside from Earth, we have found some that might have liquid water, an oxygen-rich atmosphere, a relatively-close-to-Earth gravitational acceleration on its surface. But there’s no real likelihood that we’ll ever be able to get to any of those… like… ever. And I’d think probably even those would require some teraforming to be habitable.
I wish people would realize that terraforming is the only way we’re going to colonize other planets.
Sci-fi showed us landing on Earth-like planets and making a new home. Reality will show us dying in a completely alien biosphere as bacteria and viruses we have zero resistance against ravages our bodies the moment we’re exposed to it. And we’d expose the new biosphere to pathogens it has zero resistance to.
We might be able to adapt by living in a protected environment (i.e. our biosphere) and slowly exposing generations of our descendants to the new biosphere. But many, many of us would die in the process. Not to mention genetic mutations.
“Have?”
If by “we” you mean humans, we only “have” one planet. And it’s habitable for now.
Aside from Earth, we have found some that might have liquid water, an oxygen-rich atmosphere, a relatively-close-to-Earth gravitational acceleration on its surface. But there’s no real likelihood that we’ll ever be able to get to any of those… like… ever. And I’d think probably even those would require some teraforming to be habitable.
I wish people would realize that terraforming is the only way we’re going to colonize other planets.
Sci-fi showed us landing on Earth-like planets and making a new home. Reality will show us dying in a completely alien biosphere as bacteria and viruses we have zero resistance against ravages our bodies the moment we’re exposed to it. And we’d expose the new biosphere to pathogens it has zero resistance to.
We might be able to adapt by living in a protected environment (i.e. our biosphere) and slowly exposing generations of our descendants to the new biosphere. But many, many of us would die in the process. Not to mention genetic mutations.