Earth’s Moon - Introduction to Planetary Geomorphology - page 64

(a)

(b)

Figure 4.6. Apollo 12 astronaut Pete Conrad examined the Surveyor
3 television camera, as shown in this photograph taken by astronaut
Al Bean. The Surveyor camera and the scoop were returned to Earth
for analysis (NASA AS 12 - 48 - 7133).

progressed, the time spent on the Moon and the array of
scienti c investigations increased. The next Apollo mission
was slated for a more complex highland site but, as well
documented by the movie of the same name, Apollo 13
experienced an explosion on the way to the Moon, and it
was only through the heroic work of the astronauts and the
ground crew that disaster was averted. The scienti c goals of
the Apollo 13 mission, which were to study and sample
deposits associated with the formation of the Imbrium
impact basin ( Fig. 4.11 ), carried over to Apollo 14.
The payloads and goals for the last three Apollo mis-
sions (15, 16,and17) were substantially enhanced with
the addition of roving vehicles, giving the astronauts
mobility to carry out longer traverses ( Fig. 4.12 )andto
sample more diverse terrains.
In parallel with the Apollo program, the Soviet Union
continued a series of highly successful unmanned lunar
missions, including the first use of robotic roving vehicles
( Fig. 4.13 ) and the autonomous return of samples to Earth
from three sites on the Moon, including core samples.
Although the total mass of their returned samples was
small, they provided critical data on lunar regions to
complement

Figure 4.5. (a) An Apollo 16 photograph of Alphonsus crater
(~125 km in diameter) showing the same features as seen earlier
from Ranger IX (shown in part (b)), as well as other, similar features.
The dark haloes are considered to be pyroclastic deposits (NASA AS
2478). (b) A Ranger IX image (Frame B-75) of part of the floor of
Alphonsus crater moments before impact of the spacecraft, showing
elongate, dark-halo volcanic craters associated with fractures.

A total of 382 kg of lunar samples was returned to Earth,
more than half of which remains untouched, awaiting new
analytical techniques. This means that substantial samples
are still available for study by scientists around the world. In
addition to the return of samples, diverse other Apollo
experiments were conducted, including establishing a seis-
mometer network, measurements of the remnant magnetic
field, and remote sensing of the surface from orbit.
Apollos 11 and 12, while returning new critical data, were
geared primarily toward engineering tests and involved land-
ings in relatively smooth mare sites. As the Apollo series

those visited by the Apollo astronauts

( Fig. 4.1 ).
With the return of the Apollo 11 samples and the initial
results which they revealed, NASA organized the first of
what would become the premier scienti c meeting for