“After the Chief gets his sample,” Dr. Kemp continued, “I’ll try a few things, like sonogram and x-ray. I’ve already determined that it’s not affected by magnets.”

“Does he have a pulse?”

“In the arm, you mean?” Dr. Kemp shook his head. “I’m not sure about how the interface is set up, but I doubt there’s anything biological distal to the point where metal meets flesh.”

Captain Jennings frowned and stared at the sick bay door for a few seconds. “What are our options, doctor? Is amputation viable?”

“That’s my go-to plan, actually, unless something comes up to rule it out. Pritchard can get a new one grown as soon as he’s back on Earth. It’s not like none of us can afford it, now.” Despite the gravity of the situation, the men shared a quick smile.

“All right. Use your discretion, Doctor,” the captain said. “Keep me informed.”

* * *

Ivan held up his hand. His flesh was chrome, up to halfway up the forearm. “What is it, doc? What’s happening to me?”

“I’ve already described the physical aspect, Ivan. But the why and the how? I have no idea.”

“This is from the stuff I got on my arm. It must be.”

“It doesn’t look the same. The stuff on your suit was grayish, and liquid. But yeah, it’s reasonable to conclude that the gunk caused this in some way.”

“What do I do?”

Kemp pulled up a stool and sat in front of Ivan. “We don’t know anything about this thing, and I don’t think we can afford a wait-and-see stance. I’d like you to consider amputation. Stop it before it spreads, assuming it will spread.”

“Yeah, I get it. And I can get a new arm grown when we get home.” Ivan was silent for a few seconds, staring at his hand, slowly turning it. “Okay. Do it. Before I chicken out.”

* * *

Charles Kemp looked down at the notes, charts and images arrayed on his active desktop. He pushed the items around, but no alternate arrangement magically cast the data into a sane explanation.

Kemp blew out a hard breath, then pushed the intercom. “Captain, please, Astra.”

A moment later, the captain’s voice came from the intercom. “You have a report, doctor?”

“Um, yes, sir. Lots of data, not a lot of explanations, though there’s a very organized interface between the biological and artificial parts of the arm. As I expected, the blood vessels end at that interface. But, interestingly, they aren’t just tied off. The arteries and veins have been specifically tied together so that blood flow is unimpeded. Nerve interfaces are organized and efficient including, I might add, parasympathetic functions.”