Jim Irwin is photographed beside the Lunar Roving Vehicle, with Mount Hadley in the background. Seen on the back of the Rover are two sample collection bags mounted
on the gate, along with the rake, both pairs of tongs, the extension handle with scoop probably attached, and the penetrometer. Credit: NASA
appearance, Scott placed it into a
sample bag by itself. It would be labeled as sample number 15415, but
a keen journalist, inspired by the term
“petrogenesis”, the study of the origin of igneous rocks, would later offer
it a far more lofty title: “The Genesis
Rock”, a sample of the original lunar
crust, coming from one of the earliest
epochs of the Moon’s history, some
4.1 billion years ago.
This date was reached by geologists at the University of New York at
Stony Brook and proved to be almost
1.5 billion years older than the oldest
rocks found on Earth. If the Moon
was any older than that, noted Chaikin, it wasn’t much older; the Solar
System itself was thought to have
formed only a few hundred million
years earlier.
Back in the vicinity of Falcon, shortly before 2:00 p.m. EDT and five hours
into their second Moonwalk, Scott
and Irwin had other chores to finish;
first, there was the need to complete
drilling the heat-flow hole which had
hit resistant soil the previous day.
Scott had already noticed inside
the lander that his injured fingers
were starting to turn black and so
had to summon as much strength
as he could muster—bringing his
hands right up close to his chest
just to squeeze the drill’s trigger—to
complete the task. He could physically stand only about a minute of
the pressure on his fingernails, before
breaking off for a breather. At length,
both sensor packages were in place
to a depth of about 5 feet (1.5 meters).
However, when Scott attempted
to extract the core sample which,
at about 8 feet (2.4 meters) long,
was the deepest such sample yet
attempted on the Moon, he managed to lift it slightly, but it refused
to budge any further. Joe Allen told
him to leave it until tomorrow’s final
excursion.
Meanwhile, Irwin dug a trench
and used a penetrometer to test
the bearing strength of its walls and
floor. “If you think digging a ditch is
dog’s work on Earth,” he wrote, “try
digging a ditch on the Moon. The
big limitation is the suit and the fact
that you are clumsy at one-sixth-G.
I had practiced on Earth and come
up with a technique that most dogs
use. You spread your legs and push
the dirt between them. I solved a
dog’s job with a dog’s technique.
This method worked perfectly on the
Moon.”
He easily dug through a fine grey
material which he likened to talcum
powder, and then a coarser, darker
soil, but had to give up on reaching
a very resistant layer which, although
it looked moist, had all the consistency of hardpan.
They wrapped up the second
Moonwalk by planting the American
flag and loading that day’s rock box
aboard Falcon. Not only had most of
the equipment operated flawlessly,
but the live—and color—images
provided by the Earth-operated television camera on the rover was a far
cry from the crude black-and-white
pictures of Apollo 11.
Furthermore, Scott and Irwin had
truly done their mentor, Lee Silver,
proud through their geological
descriptions. “I’m told,” Joe Allen
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