Spacemen



The Spacemen are a race of green-skinned humanoids that inhabit an asteroid located a few thousand miles away from Earth.

In the 1950s, during one of humanity's early spaceflight missions, a NASA astronaut is abducted by this race, after they discover his spacecraft orbiting their homeworld. Superboy and Krypto take flight this world to rescue the astronaut, but Superboy's super powers are stolen by a strange Energy Transference Device that they have.

Krypto battles the Super Spaceman, who got Superboy's powers and he rescues the Boy of Steel, and in turn, they both stop the Spacemen Fleet from attacking Earth, which they planned to conquer by means of an alien invasion.

Technology
The technology that the Spacemen possessed was incredibly advanced. They had a device that was capable of draining energy from superhuman beings, such as Superboy, and then transferring that energy into one of themselves.

They also had a brilliantly built city that had large glass-like domes, presumably to keep their atmosphere inside, because presumably the asteroid that they inhabited didn't have an atmosphere.

They also had spacecraft that appeared to be more advanced than that of what Earth's was at that time. Considering that their race lived in dome cities, it seems unlikely that these were colonies, implying that their world wasn't nessasarilly their native world, and that they or the species that they evolved from could have been from another planet.

Physiology
Very little is known about their physiology, but they had green skin, no hair, and had unusually strange shaped ears and faces that were somewhat featureless, like they are difficult to tell apart from another.

Considering that they live on an asteroid so close to Earth, which is indeed in the same solar system as Mars, it is possible that their species are descendants of Green Martians. Indeed, considering their skin color is green, and their proximity to Mars, it is possible, but just a theory, which has by no means ever been suggested.

Physically, as far as strength is concerned, they don't seem to be any superior to humans at all, which means if they are descendants of Martians then they somehow lost the abilities of their ancestors. However, when using the energy transference device, they were able to steal the superpowers of at least one Kryptonian teenager, which was Kal-El.

Culture
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