Apollo 17: Rambling through a boulder field.
Apollo is over. You and I have flown every mission since the start, walked together on the moon during six of them, making 14 EVAs exploring expanded landing sites in ever-growing complex missions — just as I hoped when I began marking these 50th anniversaries with Gemini in 2015. I’m sure I was inspired by childhood when I imagined myself flying every flight.
And I truly feel as if we’ve flown all these missions, landed six times on the moon. What memories stand out from our moonwalks?
We were only supposed to range 70 ft. from the Lunar Module, Eagle. I see us working at our cosy base camp, ranging back and forth to the Modular Equipment Stowage Assembly (MESA), our work station that unfolded from Eagle’s side. That’s my central memory, us standing there.
And then I break from the plan — and dash behind the LM, run 165 feet to the edge of a large crater. It drops down before me — I calculate I can only afford three minutes for the venture. But for three minutes, I am a true explorer.
Embarking on the first geological traverse of the Apollo program, the forerunner of all to come, strikes a high note. It’s our second moonwalk, and we push out first for a crater out there a hundred yards west of where our lunar Module, Intrepid, sits. Called Head crater, in a group of craters called the Snowman, we traverse its crown.
Hey, look at that! Where our boots kicked up the dirt, it’s lighter underneath, perhaps ray material kicked up from Copernicus 230 miles to the north.
We’ve begun a walk that will take us in a loop of nearly a mile, ending with inspection of the 1967 Surveyor probe sitting on the slope of a crater behind Intrepid.
“Head on out.” I remember most vividly heading out for the slopes of Cone crater, aiming for our first geological stop, “Point A,” which appears in line with Cone crater rising in the background. We’re pulling our two-wheeled cart, the Modularized Equipment Transporter. The hummocky territory of Fra Mauro hides craters in depressions — and these craters form our mileposts on the way up to Cone. Already we are experiencing trouble determining where we are, a hint of things to come. And not only for us on the climb ahead. For all who walk the moon will find it difficult to judge distances and sizes.
Check the map. “That’s Weird.” Weird crater– oddly shaped with lobes, as it is actually three overlapping craters. “And if we head to the north of that, we’re in business.”
“OK, that means that Point A is, in fact down in the valley.”
“Probably ‘A’ right here, is it not?” We take samples and readings with a portable magnetometer. In fact, after the mission we will discover we are actually far short of “Point A.”
Exploring the channel of Hadley Rille stands out. “Are we going to have time to sample bedrock here?” Come on, come on — let us at it.
Houston thinks a moment. “If you think you can reach true bedrock, then we’re willing to give up the mare sampling.”
It’s a deal! We move downslope — hopping as we traverse to where the prize samples are amid a field of boulders. “Ease on down to this outcropping.” No problem — the degree of the slope is less than when we were up on Hadley Delta mountain. But Houston is concerned; to the TV, we’re disappearing over the lip. “How far from the edge of the rille are you?”
We’re actually over the rim, on the inside of the rille’s lip. We casually say, “Can’t tell — can’t see the lip.” Which is true — it’s just a gradual slope.
Capcom Joe Allen says, “It looks like you’re on the edge of a precipice.”
“Gosh, no — it slopes right down.”
We descend lower to the boulders. “This looks like bedrock to me.”
Let’s put the last in first place: the last geological stop of the last lunar landing. Of so many sights and experiences during three walks, including the discovery of orange soil and the sampling of Split rock, I choose this moment as most vivid: The fields of boulders and rocks splashing like ripples from the rim of Van Serg crater.
“Talk about a block field.”
“We’re going to go up there and sample along the rim.” You go up and survey what’s on the rim, leaping nimbly over small rocks, dodging between low boulders. “It’s blocky — whoo!” You describe the partially-buried blocks. “The crater itself has a central mound of blocks . . . intensely shattered as are the ones on the wall.”
I join you on the rim, ready to work with my hammer, and we begin sampling. We’re tired and our voices are thick with fatigue.
I’ve left Apollo 16, a mission generally overlooked, for last and best. The Descartes site impressed me greatly, in highlands so different than the other sites, unbelievably rugged. I did not expect that.
I picture us starting out on the second EVA, a Rover sprint to Stone Mountain where we hoped to find volcanic rocks. Our Rover bounds across the rays of ejecta from South Ray Crater through a highlands world of rocks, boulders and craters upon craters. We’re heading south — on the ray which is “just covered with blocks and holes.” We’ve gotta swerve this way and that to avoid the bigger rocks and blocks. And now and then the back wheels break loose in the soft dirt.
“Yeow! Whoo! Man, that was a great big skid. We’re doing 10 clicks, Tony.” Clicks means kilometers per hour, and ten is the Rover’s top speed. Tony is science-astronaut Tony England, our Capcom in Houston.
“We’ve gotta get out of this,”
“Tony, apparently this ray is pretty extensive. We haven’t got out of this cobble field yet.” We’ve driven about 8 min. so far, a half mile into our 2.6 mi. drive onto the mountain slopes.
And that’s where I want to leave Apollo, with the image of driving off for the mountains. It’s been a privilege exploring the moon with you.
Yet you and I are not finished. We’ve got Skylab and the Space Shuttle beyond. Get ready — Skylab launches in less than five months.
— Eunice Tiptree