To drill this, they made us stay in the MAV simulator for 3 miserable days. Six people in an ascent vehicle originally designed for a 23 minute flight. It got a little cramped. And by “a little cramped” I mean “We wanted to kill each other”.
Once we got out, Commander Lewis declared “what happened in Missed Orbit stays in Missed Orbit.” It may seem trite, but it worked. We put it behind us and got back to normal.
I’d give anything for just five minutes of Missed Orbit training. I’m really feeling alone lately. Up till this road trip, I’ve been too busy to mope. But the long, dull days with nothing to do really drives it home. I’m further away from other humans than anyone has ever been.
Man, I hope I get Pathfinder working again.
LOG ENTRY: SOL 94
Home sweet home!
Today I write from my gigantic, cavernous Hab!
The first thing I did when I got in was wave my arms wildly while running in circles. Felt great! I was in that damn rover for 22 sols, and couldn’t even walk without suiting up.
I’ll need to endure twice that to get to Ares 4, but that’s a problem for later.
After a few celebratory laps around the Hab, it was time to get to work.
First, I fired up the Oxygenator and Atmospheric Regulator. Checking the air levels, everything looked good. There was still CO2, so the plants hadn’t suffocated without me exhaling for them.
Naturally I did an exhaustive check on my crops, and they’re all healthy.
I added my bags of shit to the manure pile. Lovely smell, I can tell you. But once I mixed some soil in, it died down to tolerable levels. I dumped my box o’ pee into the Water Reclaimer.
I’d been gone over three weeks, and had left the Hab very humid for the sake of the crops. That much water in the air can cause any amount of electrical problems, so I spent the next few hours doing full systems checks on everything.
Then I kind of lounged around for a while. I wanted to spend the rest of the day relaxing, but I had more to do.
Suiting up, I went out to the rover and dragged the solar cells off the roof. Over the next few hours, I put them back where they belonged, wiring them into the Hab’s power grid.
Getting the Lander off the roof was a hell of a lot easier than getting it up there. I detached a strut from the MAV platform and dragged it over to the rover. Leaning it against the hull and digging the other end in to the ground for stability, I had a ramp.
I should have brought that strut with me to the Pathfinder site. Live and learn.
There’s no way to get the Lander in the airlock. It’s just too big. I could probably dismantle it and bring it in a piece at a time, but there’s a pretty compelling reason not to.
With no magnetic field, Mars has no defense against harsh solar radiation. If I were exposed to it, I’d get so much cancer, the cancer would have cancer. So the Hab canvas shields from electromagnetic waves. This means the Hab itself it would block any transmissions if the Lander were inside.
Speaking of cancer, it was time to get rid of the RTG.
It pained me to climb back into the rover, but it had to be done. If the RTG ever broke open, it would kill me to death.
NASA decided 4km was the safe distance, and I wasn’t about to second-guess them. Driving back to where Commander Lewis had originally dumped it, I ditched it in the same hole and drove back to the Hab.
I’ll start work on the Lander tomorrow.
Now, to enjoy a good, long sleep in an actual cot. With the comforting knowledge that when I wake, my morning piss will go into a toilet.
LOG ENTRY: SOL 95
Today was all about repairs!
The Pathfinder mission ended because the Lander had an unknown critical failure. Once they lost contact with the Lander, they had no idea what became of Sojourner. It might be in better shape. Maybe it just needs power. Power it couldn’t get with the solar panels hopelessly caked with dust.
Setting it on my workbench, I pried open a panel to peek inside. The battery was a lithium thionyl chloride non-rechargeable. I figured that out from some subtle clues: the shape of the connection points, the thickness of the insulation, and the fact that it had “LiSOCl2 NON-RCHRG” written on it.
I cleaned the solar panels thoroughly, then aimed a small, flexible lamp directly at them. The battery’s long dead. But the panels might be ok, and Sojourner can operate directly off them. We’ll see if anything happens.
Then it was time to take a look at Sojourner’s daddy. I suited up and headed out.
On most landers, the weak point is the battery. It’s the most delicate component, and when it dies, there’s no way to recover.
Landers can’t just shut down and wait when they have low batteries. Their electronics won’t work unless they’re at a minimum temperature. So they have heaters to keep the electronics warm. It’s a problem that rarely comes up on Earth, but hey. Mars.
Over time, the solar panels get covered with dust. Then winter brings colder temperatures and less daylight. This all combines into a big “fuck you” from Mars to your lander. Eventually it’s using more power to keep warm than it’s getting from the meager daylight that makes it through the dust.
Once the battery runs down, the electronics get too cold to operate, and the whole system dies. The solar panels will recharge the battery somewhat, but there’s nothing to tell the system to reboot. Anything that could make that decision would be electronics, which would not be working. Eventually, the now unused battery will lose its ability to retain charge.
That’s the usual cause of death. And I sure hope it’s what killed Pathfinder.
I piled some leftover parts of the MDV into a makeshift table and ramp. Then I dragged the Lander up to my new outdoor workbench. Working in an EVA suit is annoying enough. Bending over the whole time would have been torture.
I got my toolkit and started poking around. Opening the outer panel wasn’t too hard and I identified the battery easily enough. JPL labels everything. It’s a 40 Amp-hour Ag-Zr battery with an optimal voltage of 1.5V. Wow. They really made those things run on nothin’ back then.
I detached the battery and headed back inside. I checked it with my electronics kit, and sure enough it’s dead, dead, dead. I could shuffle across a carpet and hold more charge.
So I knew what it needed. 1.5 volts.
Compared to the makeshift crap I’ve been gluing together since Sol 6, this was a breeze. I have voltage controllers in my kit! It only took me 15 minutes to put a controller on a reserve power line, then another hour to go outside and run the line to where the battery used to be.