Apollo Lunar Surface Experiment
General ALSEP Info & Support
Left - B&W image of the 2 main ALSEP subpackages
Center - Two nice color photos of the subpackages
Right - Diagram of ALSEP packages, depicting how they were stored inside
LM SEQ bay (quad II)
The ALSEP that never was. Apollo 13 CDR Jim Lovell practicing ALSEP
deployment. Note the twin UHTs attached to the
pallets, sticking up at 45 degree angles from them.
The central station relayed data
to and from the experiments and routed power from the RTG to the experiments
of the ALSEP. It was really the heart of the ALSEP station.
Left - Diagram depicting central station main structures. The top and
bottom structures were actually the subpackage pallets
Center - Component layout of central station
Right - Antenna aiming mechanism
Left 2 images - Apollo 14 central station at Fra Mauro
Right - Did someone ask for details?
Thermoelectric Generator (RTG)
The RTG produced 70 watts of electrical
power for the ALSEP by converting the heat of decaying plutonium directly
into electricity. The core was a SNAP 27 system. For its' time, it was
a very sophisticated system.
Left - RTG nuclear fuel cask on LM mockup. The cask was designed to
prevent nuclear contamination of the earth should the nuclear core ever
reenter the atmosphere - which is exactly what happened when the Apollo
13 LM Aquarius brought the stricken CSM & crew home
(Photo courtesy Sven "Ninfingers" Knudson)
Center 2nd & 3rd images - Diagrams of RTG
Right - RTG fueling procedure. The hand tools used to fuel the
covered in the next section. The fueling
procedure itself is covered in depth here
Left - Apollo 14 RTG with central station in background. Note that,
unlike the experiments which used ribbon cables, the RTG used a heavy gauge
round cable to connect it to the central station
Right - Apollo 16 RTG. Can you say "Caked with dirt"?
RTG Dome Removal Tool and Fueling Tool
Also go here
for in depth information on the RTG fueling
There were 3 primary hand tools used with the ALSEP. Two of these
were single function tools, the RTG Cask Dome Removal Tool and the RTG
Fuel Transfer Tool. These were used to handle the radioisotopic fuel
of the RTG.
|All 3 of the Apollo Hand Tools
||RTG Fueling Tool
||Al Bean removing
RTG fuel rod from
cask. All 3 tools are
visible and labeled:
1. Fueling tool
2. Dome Removal Tool
Universal Hand Tool
The other tool, the Universal Hand Tool (UHT), was designed to fit
into sockets on the ALSEP experiments and do everything from removing Boyd
bolts, to opening arrays, to pointing the experiments. The UHT was
also adapted to be used as the LRV Sampling Tool on Apollo 17 as well as
the Surface Sampling Tool.
|Jim Irwin practices
works at the
with a UHT
|UHT as used
as the LRV
The ALSD was used to drill hollow
tubes into the lunar surface. These tubes were used for emplacement of
probes for the heat flow and neutron probe experiments, as well as to obtain
deep core tubes of the regolith for geology
Left - Apollo 15 CDR David Scott threads a heat flow probe down the
tube of a bore stem. Note the drill head in background and bore stem
rack in foregraound.
Right - Diagram of drill and associated hardware
Surface Close-up Camera
Left - Nice photo from the NASM
Right - Buzz Aldrin unpacks the ALSEP from Eagle, with ALSCC in foreground
Close-up stereo pair of lunar soil from Apollo 12 ALSCC
Also known as "the Gold camera", after it's inventor Tommy Gold, the
ALSCC took stereo pairs of close-up photos of the lunar surface.
These images were used to help determine the properties of the lunar soils.
Although this camera wasn't technically part of the ALSEPs, I've included
it here for clarity.
The ALSCC was an "aim and shoot" unit which needed very little of the
crewmen's time to operate. It was totally self-contained, requiring
only that a crewman remove the film magazine when done using it.
Modeler's note: although
there are no existing models of these devices, that may not always be the
case. I've always wanted to reproduce at least some of these to stand next
to an Apollo figure. Someday... someday....
Go back to ALSEP main page
to first ALSEP experiment report