Thrones of Mars

This story uses only what we have today, or will be developed from what we have.
Some say we cannot go with the technology we now use. We can, and we will; only the will is needed.
The astronauts and cosmonauts on the Orion Program thought they were alone in building a spaceship to go to Mars and back. As they were building the ship, they found that they were being helped by minds much bigger than theirs - then they find a machine that was not made on Earth by men.
The appearance of a man working on the outside of the spaceship without a spacesuit can be alarming, so he tends to stay inside.
I reiterate:
This story uses only what is available today, or will be developed from what we now have.
There are fantasies, no death rays, superheroes, or machines defying the laws of physics.
"The mission really is establishing permanence on another planet in the Solar System."
Dr. E. E. 'Buzz' Aldrin, Apollo 11 astronaut.