Lovecraft was right
Could humans live on alien worlds the way they have on Earth from the beginnings of the hominid lineage?
Well, within the Solar System, so far there is just one world capable of supporting our kind of life -- Earth itself. But we could plant bases and even underground colonies on the Moon and Mars, even now -- it's only a matter of going through with what we've already got started on -- and eventually we could terraform Mars. We might also, someday, be able to drag Venus back from the fire, let her cool down, and terraform her. We could do the same to various moons of Jupiter and Saturn (though perhaps we might want to leave a couple of those alone, as they are large icy bodies that probably have deep oceans underneath their icy surfaces, oceans that could harbor bacterial life of their own). (Mercury is a different story. As close to the Sun as he is, he'd make a dandy scientific observation platform for studying solar phenomena as well as various populations of near-Earth asteroids (NEOs) and any bodies orbiting between Mercury and the Sun. Establishing scientific bases there (probably in the shadows within deep craters at Mercury's poles, to avoid certain air-conditioning issues; the heat differential between the craters' rims and their interiors could provide power for the bases, and internally refrigerated rovers could be used to explore Mercury's surface) could give us invaluable knowledge about the Sun, Mercury, and the region of the Solar System between the two. We might even want to mine Mercury for various mineals, but that could be done with automated mining equipment; bases for them could be established in, lava tubes or other underground redoubts shielded from the fierce energy of the Sun and the occasional solar tantrums, especially huge coronal mass ejections, and maintenance operations could be carried out in those underground redoubts. But only extreme desperation would drive anybody to plant a full-fledged colony on Mercury and try to terraform the place, and the odds of that succeeding -- well, the old cliche about snowballs in certain places applies well here.)
How about worlds of other stars?
There are bound to be numerous worlds out there resembling Earth as our world was during the Archaean or Proterozoic Eons, or even the early periods of the Paleozoic Era of the Phanerozoic Eon of her evolution. There are also bound to be many in stages of evolution beyondthe Holocene Epoch of the Cenozoic Era of the Phanerozoic Eon -- our time -- but those are very likely to be rather inhospitable for life as we know it.
Even so, considering that there are hundreds of billions of stars in the Milky Way, and that in just the last 18 years, our ongoing searches for exoplanets in regions of the galaxy relatively close to the Solar System has already come up with 402 of them (and counting!), there are bound to be at least a few millions of worlds in the Goldilocks Zones of their stars, have liquid water on their surfaces (or under thick layers of ice), enough carbon dioxide in their atmospheres to keep them from freezing, but not so much that they roast, and the right balance of minerals in their crusts to provide the nutrients needed by organic, water-based life. The life on most of those worlds is likely to be microbial, with, at the very most, a very light salting of tiny complex life forms. But out of those that do harbor life, at any time a few could well be suitable for colonization by today's terrestrial life-forms.
Of course, of those few worlds, some would have biospheres and life-forms so bizarre that we couldn't easily live on the surface even if we wanted to -- the biochemistry of that life would be too different from ours, generating deadly toxins and Visit W3Schools!, along with a plethora of killer allergens, that neither we nor our terrestrial stock animals, cultivars, and pets could handle, even using genetic engineering to modify us biochemically and physiologically. Behaviorally and ecologically speaking, many of the creatures on such rare Earths would be parasites magnificently equipped to parasitize us and the Earthly creatures we took there with us, while we would have few or no defenses against them; microbial life there would already have the drop on us, because we would likely only discover the dangerous ones when they Did Things to us, giving them a dreadful edge over Earth life; and many or most of the larger life-forms would come at us out of left field, before we knew they were there and what they could do to us. And then there's the possibility -- no, strong likelihood -- that in many cases those worlds would have a higher proportion of heavy metals in their soils, to which their life forms had adapted, making them intensely poisonous to eat, and some of them so venomous that a drop of their venom would kill a big man stone-dead in a minute or two. We'd have to go about trying to colonize such worlds very carefully, and even then, they could do a real number on us before we knew what was happening.
So okay, say we find paradise among the stars, and we go there, and start to establish colonies on that world. Say that this world is so like Earth that at worst, all we have to deal with are creatures resembling common terrestrial weeds, Amanita mushrooms, terrestrial honeybees, terrestrial spiders, clever and enterprising terrestrial fish, pretty little terrestrial cephalopods and jellyfish, and the odd terrestrial bacillus.
. . . And after contemplating that biotic alien laundry-list, in search of something to relieve anxiety, we pick some of that nice plant growing by the wayside and toke up on it . . .
The Old Man was right: assuming the smoker survives that last experience, you can bet the report that poor bastard gives of life-forms on that world will top anything that H. P. Lovecraft ever dreamed about in his worst nightmares!
Well, within the Solar System, so far there is just one world capable of supporting our kind of life -- Earth itself. But we could plant bases and even underground colonies on the Moon and Mars, even now -- it's only a matter of going through with what we've already got started on -- and eventually we could terraform Mars. We might also, someday, be able to drag Venus back from the fire, let her cool down, and terraform her. We could do the same to various moons of Jupiter and Saturn (though perhaps we might want to leave a couple of those alone, as they are large icy bodies that probably have deep oceans underneath their icy surfaces, oceans that could harbor bacterial life of their own). (Mercury is a different story. As close to the Sun as he is, he'd make a dandy scientific observation platform for studying solar phenomena as well as various populations of near-Earth asteroids (NEOs) and any bodies orbiting between Mercury and the Sun. Establishing scientific bases there (probably in the shadows within deep craters at Mercury's poles, to avoid certain air-conditioning issues; the heat differential between the craters' rims and their interiors could provide power for the bases, and internally refrigerated rovers could be used to explore Mercury's surface) could give us invaluable knowledge about the Sun, Mercury, and the region of the Solar System between the two. We might even want to mine Mercury for various mineals, but that could be done with automated mining equipment; bases for them could be established in, lava tubes or other underground redoubts shielded from the fierce energy of the Sun and the occasional solar tantrums, especially huge coronal mass ejections, and maintenance operations could be carried out in those underground redoubts. But only extreme desperation would drive anybody to plant a full-fledged colony on Mercury and try to terraform the place, and the odds of that succeeding -- well, the old cliche about snowballs in certain places applies well here.)
How about worlds of other stars?
There are bound to be numerous worlds out there resembling Earth as our world was during the Archaean or Proterozoic Eons, or even the early periods of the Paleozoic Era of the Phanerozoic Eon of her evolution. There are also bound to be many in stages of evolution beyondthe Holocene Epoch of the Cenozoic Era of the Phanerozoic Eon -- our time -- but those are very likely to be rather inhospitable for life as we know it.
Even so, considering that there are hundreds of billions of stars in the Milky Way, and that in just the last 18 years, our ongoing searches for exoplanets in regions of the galaxy relatively close to the Solar System has already come up with 402 of them (and counting!), there are bound to be at least a few millions of worlds in the Goldilocks Zones of their stars, have liquid water on their surfaces (or under thick layers of ice), enough carbon dioxide in their atmospheres to keep them from freezing, but not so much that they roast, and the right balance of minerals in their crusts to provide the nutrients needed by organic, water-based life. The life on most of those worlds is likely to be microbial, with, at the very most, a very light salting of tiny complex life forms. But out of those that do harbor life, at any time a few could well be suitable for colonization by today's terrestrial life-forms.
Of course, of those few worlds, some would have biospheres and life-forms so bizarre that we couldn't easily live on the surface even if we wanted to -- the biochemistry of that life would be too different from ours, generating deadly toxins and Visit W3Schools!, along with a plethora of killer allergens, that neither we nor our terrestrial stock animals, cultivars, and pets could handle, even using genetic engineering to modify us biochemically and physiologically. Behaviorally and ecologically speaking, many of the creatures on such rare Earths would be parasites magnificently equipped to parasitize us and the Earthly creatures we took there with us, while we would have few or no defenses against them; microbial life there would already have the drop on us, because we would likely only discover the dangerous ones when they Did Things to us, giving them a dreadful edge over Earth life; and many or most of the larger life-forms would come at us out of left field, before we knew they were there and what they could do to us. And then there's the possibility -- no, strong likelihood -- that in many cases those worlds would have a higher proportion of heavy metals in their soils, to which their life forms had adapted, making them intensely poisonous to eat, and some of them so venomous that a drop of their venom would kill a big man stone-dead in a minute or two. We'd have to go about trying to colonize such worlds very carefully, and even then, they could do a real number on us before we knew what was happening.
So okay, say we find paradise among the stars, and we go there, and start to establish colonies on that world. Say that this world is so like Earth that at worst, all we have to deal with are creatures resembling common terrestrial weeds, Amanita mushrooms, terrestrial honeybees, terrestrial spiders, clever and enterprising terrestrial fish, pretty little terrestrial cephalopods and jellyfish, and the odd terrestrial bacillus.
. . . And after contemplating that biotic alien laundry-list, in search of something to relieve anxiety, we pick some of that nice plant growing by the wayside and toke up on it . . .
The Old Man was right: assuming the smoker survives that last experience, you can bet the report that poor bastard gives of life-forms on that world will top anything that H. P. Lovecraft ever dreamed about in his worst nightmares!