Finding Life on Mars: Excerpt 2

I shook my head, lifted off the helmet, stripped away the mask that covered my mouth and nose. Took one breath, exhaled, replaced the mask. Feeling no ill effects for a minute, I took off the mask again, took two breaths. I repeated the process until I breathed the interior air continuously.
"Why did you do that?" Merlin asked.
"I did not wish to risk you. You are too important to the colony," I said.
"The colony?"
"Yes."
He nodded, turned away so I could see nothing of his face. Then he started to take off his own helmet.
"Too much risk," I said. "If there is some toxin at work in here it may take time to affect..."
"What happens to you happens also to me," Merlin repeated. "You are too important to risk."
"I am of no consequence," I said.
"Perhaps, on the cosmic scale. And while you have some value to the colony, to me you are everything." The helmet was off now, mask lifted to rest on his forehead. He still faced away from me but his voice came clear through the atmosphere rather than through the headset now. "Parents die for their children. It is perverse for children to die for their parents. Illogical and undue."
"Tell me how it was," I said, rather than argue. "The last days on Earth. The first days here. How was it to fly through space?"