Meant to post about this yesterday, but I was pretty wiped from a long day battling with sandbox limitations and permissions while building out a new lab1, not to mention a long week, month, year, uh...yeah, I'm pretty tired generally, although in better shape than astronauts after an EVA on the lunar surface.
Anyway, Dave and Jim got to bust out some new wheels on July 31. Chaikin:
It would have been a strange sight, had anyone been there to witness it: a four-wheeled craft heading out among the craters, bearing two space-suited men. The Rover was less a car than a spacecraft on wheels, with its own navigation computer, communications system, and cargo space for such essentials as maps, geology tools—and moon rocks.
For all its sophisticated technology, there was still a hobby-shop look to this moon car, with its antennas and folding lawn-chair seats and tool racks. It had been designed, built and tested by Boeing in less than two years; the success of the mission rode on it.
Aboard Rover 1, the ride was more exciting than anyone, including Scott and Irwin, had banked on. Though the Rover averaged only 5 to 7 miles an hour, it seemed more than fast enough to the two men perched atop it. Every time the Rover hit a bump—and the “plain” at Hadley was all bumps and hollows—it took flight. Each new obstacle set one or two wheels off the ground for a long moment.
As an added encumbrance, the steering on the Rover’s front wheels was inexplicably out of commission, forcing Scott to rely on the rear-wheel steering alone. The ride was especially harrowing for Jim Irwin, who felt as though he were strapped onto a bucking bronco, especially when Scott had to swerve to avoid a crater. The transmissions from the Rover were punctuated every so often with a warning from Scott—“Hang on!”—followed by Irwin’s grin-and-bear-it laughter.
Scott and Irwin were having as much trouble gauging distance on the airless, treeless moon as everyone had before them. But they were in no danger of losing their way, thanks to the Rover’s navigation system; it clicked off readings of heading and distance as Scott drove. Irwin, meanwhile, followed along on the photo map. Aside from the usual difficulty in recognizing landmarks, the maps were misleading:
Many of the craters and bumps that looked so prominent on the over-enhanced photos were barely noticeable on the real moon. But one landmark was impossible to miss, and as the Rover headed southwest, over the undulating mare, both men suddenly caught sight of it: “There’s the rille!” For a time, they followed the canyon’s curving edge, then stopped at Elbow crater to gather samples. Soon they were driving again, heading uphill toward St. George; Scott could feel the difference.
Once released, the rover—our “Moon car”—slowly descended to the surface; a brilliant piece of engineering with sealed electric motors in the hub of each wheel. After securing its joints with pins, I climbed aboard to test its operation. Almost immediately, I realized that there was a problem with the front steering.
This was perfectly manageable with rear steering and eventually righted itself. Even so it was a pretty bumpy ride. After loading a rack at the rear with the geological equipment we would need for our first day of exploration we climbed aboard—something of a challenge since the suits did not bend easily into a seated position—and started the engines.
Driving the rover was actually more like flying an airplane, albeit with four wheels, than driving a car. Instead of a steering wheel, which would have been very difficult to grasp in our bulky suits, it was controlled with a joystick mounted on a control console between my seat and Jim’s.
Despite our maximum speed of only 7 or 8 mph, the reduced gravity and very irregular surface meant one or more of the independently suspended wheels lifted away from the surface every time we hit uneven terrain. No part of the lunar surface was totally flat or even. It was all rolling and irregular with a wide variety of small and large craters, some with debris inside.
Maneuvering around the larger craters and across this combination of rolling hummocks and fine- to coarse-grained lunar soil required intense concentration. Driving into the sun was the most difficult, since the glare caused a “wash-out” of the surface features. Though the rover could turn on a dime and had very good traction and power, the wire-mesh wheels kicked up impressive rooster-tails of dust, which were deflected by large fenders. It all made for a ride like a cross between a bucking bronco and a small boat in a heavy swell.
“This really is a rockin’ and rollin’ ride. Hang on,” I told Jim as we headed southwest in the direction of the first of our destinations, Elbow Crater and the northeast flank of St. George Crater on the lower flank of Mt. Hadley Delta.
Why they were there (Scott):
Each stopping point on our three days of lunar traverses had been selected to allow us to examine contrasting aspects of the Moon’s complex geology, much of which was largely a mystery. Our ultimate goal was to throw light on the origin of our nearest galactic neighbor—which had long been the source of speculation and serious scientific debate. Greater knowledge about the Moon’s genesis was expected to throw more light on the origin of our own planet, of the Sun and of our entire solar system.
Over time three competing theories about the origin of the Moon had evolved. The so-called “sister” theory held that the Earth and the Moon were born at the same time and of the same cloud of gas and dust. The “spouse” theory held that the Moon was born in another part of the solar system and had been forced into wedlock with our planet after moving into the Earth’s gravitational field. According to the “daughter” theory, the Moon was born of the Earth, splitting off very early on.
I bet even Michael Jackson would be exhausted after a moonwalk (Chaikin):
The mountains of the moon captivated Jim Irwin, just as he knew they would. That anticipation had been with him yesterday as he followed Scott down Falcon’s ladder. When he put his weight on the footpad, it tipped so suddenly that he went reeling backward, hanging on with one hand, until he was gazing almost straight up at the sparkling blue world he had left behind. Regaining his balance, he took his first buoyant steps into the valley, and could not suppress his elation.
The Apennines were not gray or brown as he had expected, but golden in the light of lunar morning. Their rounded, dust-covered forms reminded him of ski slopes—Dollar and Half Dollar mountains at Sun Valley. He was surprised to find that a place others had called stark and desolate could feel so friendly. The mountains surrounded Hadley Base like a cradling hand. He felt at home on the moon.
But yesterday’s exploration had taken a toll on Irwin. Not until he and Scott were back in the LM did Irwin feel the full measure of his exhaustion. Aside from the mental fatigue brought on by hours of intense concentration, and the pressure spent. The incessant glare from the sun and the bright landscape had given him a fierce headache. And he was parched; the water bag in his suit had refused to work and he’d gone more than seven hours without a drink.
Worst of all was the pain in his fingers. By the end of the moonwalk they were so sore that when it came time to take off his gloves he had to ask Scott for help. When they had settled in for the evening, Irwin used a pair of scissors to trim his fingernails all the way back; that helped. He suggested his commander do the same, but Scott declined, reluctant to do anything that might compromise his dexterity.
After the moonwalk Irwin had been overtired, and he had not slept well. Then, this morning he and Scott were awakened early by a call from mission control, to check on a water leak in Falcon’s cabin. When they looked behind the ascent engine cover, they found a couple of gallons of water that had leaked through a broken filter. Irwin was glad that Grumman had waterproofed the LM’s electronics.
Thankfully, despite all of this, Irwin felt renewed as he and Scott prepared for the second traverse. Yesterday, they’d been denied the chance for real prospecting up on Hadley Delta; now they would have one more chance to find out what the mountains of the moon had to offer.
The adventure continues...
1 - Thursday morning I did a walkthrough of our extant VPC peering exercise with the re/Start crew, and my learners asked if we could do something with AWS Transit Gateway in future, so I promised to gin something up for next time.
What seemed like it would be a really quick bit of dev work ended up taking several hours because of a variety of non-obvious constraints in the lab environment. Also, as is typical when I do this stuff, I kept going on little side quests which found their way into the architecture, tying together a bunch of different things we've explored in the last several sessions and expanding on them.
This is my happy place, but sometimes I just run out of cognitive space when doing deep tech dives. Regardless, got everything worked out, and I spent a good bit of this morning testing and writing out instructions whilst drinking coffee and watching the WNBA (what a shot by Sydney Taylor to win it for the Sky!).
PS - got a chuckle when CAPCOM Joe Allen told Dave, "buckle up for safety." When I was a wee lad, I would sing that jingle with a little twist: "buckle up for Jesus, buckle up!"
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