sand and gravel beneath a vast and deep mid-morning sky, ultramarine above, pink toward the horizon.
I was alone. Even my girlfriend was gone, the circuitry that had maintained her abbreviated personality nano-D’ed into microscopic dust.
Well, not entirely alone. Somewhere out there in all that emptiness were forty-seven men and women, the rest of my Marine insertion platoon.
First things first. Navy Hospital Corpsmen are the combat medics of the Marine Corps, but our technical training makes us the sci-techs of Marine advance ops as well. Planetology, local biology and ecosphere dynamics, atmosphere chemistry—I was responsible for all of it on this mission, at least so far as Squad Bravo was concerned.
I knew what the answers would be. This was Mars, after all, and humans had been living here for a couple of centuries, now. But I drew a test sample into my ES-80 sniffer and ran the numbers anyway. Do it by the download.
Carbon dioxide, 95 percent, with 2.7 percent nitrogen, 1.6 percent argon, and a smattering of other molecular components, all at 600 pascals, which is less than one percent of the surface atmospheric pressure on Earth. Temperature a brisk minus 60 degrees Celsius. Exotic parabiochemistries powered by the unfiltered UV from the distant sun. Thirty parts per billion of methane and 130 ppb of formaldehyde—that was from the microscopic native critters living at the lower permafrost boundaries underground, the reason we’d abandoned plans to terraform the place. Gotta keep Mars safe and pristine for the alien wee beasties, after all.
I recorded the data, exactly as if we had no idea what was on Mars, and uploaded it to the squadnet. I also needed to—
“Corpsman, front!” The voice of Corporal Lewis came over my com link. “Marine down!”
Shit! “Moving,” I said, my voice sounding uncomfortably loud within the confines of my helmet. I called up the tacsit display on my in-head, getting my bearings. There were ten green dots—the one at dead center was me—and one off to the side flashing red. I turned, getting a bearing. Private Colby was that way, 2 kilometers away. Corporal Lewis was with him.
“I’ve got you on my display,” I told Colby. Under a Level-3 comm silence, we were using secure channels—tightly beamed IR laser-com signals relayed both line of sight and through our constellation of micro comsats in orbit. The setup allowed short-range communications with little chance of the enemy tapping in unless he was directly in the path of one of our beams, but we were still supposed to keep long-range chatter to an absolute minimum.
I took a short and lumbering run, kicked in my jets, and flew.
Service Manual Download
Standard-Issue Military Equipment
MMCA Combat Armor, Mk. 10
[extract]
… including alternating ultra-light layers of carbon buckyweave fiber and titanium-ceramic composite with an active-nano surface programmable by the wearer for either high or low visibility, or for albedo adjustments for thermal control. Power is provided by high-density lutetium-polonium batteries, allowing approximately 300 hours service with normal usage depending upon local incident thermal radiation.
Internally accessible stores carry up to three days’ rations of air, water, and food, which can be extended using onboard extractors and nanassemblers. Service stores of cryogenic hydrogen and oxygen [crH2/crO2] can be carried to further extend extraction/assembled expendables.
Combat armor mass averages 20–25 kg, though with full expendables load-out this may increase to as much as 50 kilos …
Flight Mode
Mk. 10 units are capable of short periods of flight depending on local gravity, or of jet-assisted maneuvers in a microgravity environment. The M287 dorsal-mounted jumpjet unit uses metastable N-He64, commonly called meta, as propellant, stored in crogenically inert high-pressure backpack tanks.
Proper maintenance of meta HP fuel tanks is vital for safe storage, transport, and operation of jumpjet units …
Marine combat armor isn’t really designed for flight, especially in-atmosphere, but the Martian air is thin enough that it’s close to hard vacuum, and my “flight” was more a series of long, low bounds across the rocky, dark red-brown terrain, aided by the low gravity—about .38 of Earth normal. That meant I got more boost for my buck, and just a few quick thruster bursts brought me down in the boulder-strewn field where Private Colby was curled up on the sand, his arms wrapped around his left shin, with Corporal Lewis at his side.
I’d checked his readouts during my flight, of course—at least when I wasn’t watching my landings to avoid doing what I suspected Colby had just done to himself—landing like shit and breaking something. Just because you weigh less than half what you do on Earth here doesn’t mean you don’t still have your normal mass, plus the mass of your combat armor. Bones can only take so much stress, and a misstep can snap one. Colby’s data feed showed he was conscious and in pain, respiration and heart rate high, suit intact. Thank the gods for that much, anyway. A breach in the suit brings with it its own list of headaches.
“He hit a rock, Doc!” Lewis said, looking up as I slid to a halt in loose sand. “He hit a rock coming down!”
“So I see. How you doing, Colby?”
“How do you fucking goddamn think I’m fucking feeling goddamned stupid-ass bullshit questions—”
I had already popped the cover on Colby’s armor control panel, located high on his left shoulder, and was punching in my code. Before I hit the SEND key, though, I hit the transparency control for his visor, then rolled him enough that I could peer through his visor and into his eyes. “Look at me, Colby!” I called. “Open your eyes!”
His eyes opened, and I looked at his pupils, comparing one with the other. They were the same size. “Your head hurt at all?” I asked.
“Goddamn it’s my fucking leg not my head Doc will you fucking do something fer chrissakes—”
Good enough. I hit the SEND key, and Colby’s suit auto-injected a jolt of anodynic recep blockers into his carotid artery. Nananodyne can screw you up royally if you have a head injury, which was why I’d checked his pupils and questioned him first.
“Can we get him up on his feet, Doc?” Lewis asked.
“Don’t know yet” I said. “Gimme a sec, okay?”
I jacked into Colby’s armor and instituted a full scan. Infrared sensors woven into his skinsuit picked up areas of heat at various wavelengths and zipped a picture of his body into my head. The data confirmed no pressure leaks—those would have shown up as cold—but there was plenty of bright yellow inflammation around his left shin. No sign of bleeding; that would have appeared as a hot spot, spreading out and cooling to blue inside the greave. Colby was relaxing moment by moment. Those nanonarcs target the thalamus and the insular cortex of the brain, switching off the doloric receptors and blocking incoming pain messages.
Heart rate 140 and thready, BP 130 over 80, respiration 28 and shallow, and elevating adrenaline and noradrenaline, which meant an onset of the Cushing reflex. His body temp was cooling at the extremities which meant he was on the verge
