Even space: Asteromo???s 70,000 people live, work, and play in near-earth orbit.But what???s even more amazing than Soleri???s designs and grander-than-grand visions is that out in the cactus and scorpion wilds of Arizona he and his students are building one: Arcosanti.Originally planned to house a grander number, the new target for this test-bed arcology is about 5,000 residents, mostly students