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the background of most design software as an updated aerial
image. This greatly benefits the technicians in the office by PLS (Professional
gives clarity to the lay of the land and helps identify an unknown Lunar Surveyor)
giving them a snapshot of the site as the data was collected. It
object in the LiDAR. This imagery can also as be used by other
disciplines as a way to inspect the site and identify potential Did you ever look up at the night sky and think to yourself, I
issues. wonder what surveying will be like on another planet? I recall
that old NASA ad of a surveyor on Mars a few years back.
The combined dataset could also be used to create a base surface Someday there will a person who can claim to be the first
for future volume calculation of material moved either above or surveyor there, no doubt about it. But what about a little more
below the water surface at any point in the process. A second near-term? How about being a surveyor on the Moon, when
collection could be performed and the resultant digital terrain they finally build Moon Base Alpha, Craterville, Muskopolis,
model (DTM) surface can be compared to the original. R.E.Y. or whatever the name of the first development may end up
surveyors have found the accuracy of these above water level being? Imagine how expensive ginneys and hubs will be if they
surfaces are typically +/- 0.10’ in most cases, and +/-.25’ for the have to be freighted all the way from Cape Canaveral.
surface below the water. This is a great advantage for companies The Moon does not have a dipolar magnetic field. No
needing to accurately track the volume of materials moved on a
periodic basis.

On most sites where
this strategy is used,
the bathymetric data is
collected on a different
day than the UAV LiDAR
data. In most cases, these
two surveys are done on
consecutive days. The
initial processing of the
data is handled separately,
using different software
with the intermediate result being a point cloud for each. It is at
this point that a knowledgeable and qualified technician merges
the point cloud data for each survey and extracts the surface
features using in a single software. This leads to a complete opportunity then to determine a magnetic “north”. This Earth-
and seamless surface model. In addition to a richer and more orbiting slab of green cheese takes 27 days to rotate on its
accurate surface model, this workflow requires much less field axis, so this rotation could be utilized for setting up a basis of
time than a conventional survey. Working on steep slopes above directions, so that’s good. However, there is no constellation
a body of water always carries safety concerns. With the surface of satellites orbiting the Moon from which an LPS (Lunar
data being collected by UAV LiDAR, survey crews are not forced to Positioning System) could be developed, at least not right now.
‘mountain goat’ their way around the site. Therefore, the first surveyors on the Moon, the ones tasked
with laying out any non-3D-printed facilities, will need to be
Advancements in construction will lead to more and more steeped in first principals, such as survey astronomy, assuming
of these types of challenging projects combining different that is, that NASA or others are developing a lunar ephemeris.
remote sensing platforms, with the UAV LiDAR being a critical The Lunar Surveyor, (Lunodesist?) will be taking star shots and
component. R.E.Y. deploys not only UAV LiDAR and multibeam determining azimuths, relative to poles that best represent the
bathymetric survey equipment, but also vehicle and tripod lunar rotation.
mounted LiDAR systems. Surveyors will work closely with other
engineering firms, public agencies, private developers, and By the way, how does a total station do at measuring
contractors to understand what “tool” is best for the project and distances in a zero-atmosphere environment? I guess there
deploy as necessary to deliver an accurate and reliable finished would be no PPM correction. The Moon has a much smaller
product. diameter than Terra (hey – I’m an old Sci-fi fan), so curvature
would play a bigger part in plane surveying. On the plus side,
About the Author you won’t need a machete, or bear spray or snake leggings to
Jed Gibson is a California licensed Professional Land Surveyor in do your job. Will there be licensure? I wonder.
California. He is the Lead UAV LiDAR Pilot and Project Manager at
R.E.Y. Engineers, Inc., headquartered in Folsom, CA. He has been You know… it would very expensive to send surveyors to the
surveying since 2014 and has an extensive background in remote Moon and bring them back so it might end up being a one-way
sensing, land surveying, and large-scale topographic mapping trip. Of course, the engineers would get to go back home to
projects, including the Oroville Dam, the tallest dam in the United the main office, but the surveyors would have to stay at the
States. “field office”. Their last job would likely be laying out the first
Associate Surveyor, R.E.Y. Engineers, Inc. lunar cemetery, Moon-Boot Hill, as it were.
(916) 366-3040
jgibson@reyengineers.com

16 The Nevada Traverse Vol.49, No.2, 2022