Drone Adds Detail to Crater Study
Researchers from the University of Tennessee, Knoxville, have shown that when they use cameras mounted on a drone, they can develop a digital model of a crater faster and with more detail than previously possible.
Their study, “A Drone-Based Thermophysical Investigation of Barringer Meteorite Crater Ejecta,” was published in the February 2025 issue of the journal Earth and Space Science.
The work was part of the doctoral dissertation of the lead author, Cole Nypaver (MS ’19, PhD ’23), who is now a postdoctoral fellow at the Smithsonian National Air and Space Museum’s Center for Earth and Planetary Studies.
He worked with two faculty members from the Department of Earth, Environmental, and Planetary Sciences (EEPS), Assistant Professor Brad Thomson and Professor Jeff Moersch, a leader in using remote sensing to study planetary geology.
Horseback, Satellite, Drone
The EEPS researchers used an aftermarket camera mounted on an unmanned aerial system to map a portion of the ejecta from the Barringer Meteorite Crater in Arizona. Formed about 50,000 years ago, the crater is 1.2 kilometers across, and the impact of the meteorite is estimated to have thrown out nearly 100 million tons of rock, according to the US Geological Survey.
“When this crater was first mapped in the early 1960s, much of the work was done on horseback,” Thomson noted.
Today planetary geoscientists typically use data collected from orbital satellites to study impact ejecta, but the scale is about 90 meters per pixel. A high-resolution thermal camera mounted on the drone can zoom in to 23 centimeters per pixel, and co-acquired optical images can zoom in to 2 centimeters per pixel.
“One of the really mind-blowing products that result from drone optical imagery is centimeter-scale digital terrain models (DTMs) of the crater’s topography,” Thomson said. “If you wind the clock back more than 10 years, it would have been painstaking work to hand-stitch or manually combine the individual images into a mosaic, and use specialized and expensive software to derive topographic information from the overlapping stereo views.
“For this project, Jeff was able to have the drone fly through an automated sequence to collect images, throw them into a software called Pix4D on his laptop, and have a centimeter-scale DTM automatically generated by the following day. Personally, I find this remarkable.”
Taking the Temperature
The researchers were collecting data on the thermal response of materials at different times of the day, which can show whether the material is rock or sand. Sand heats and cools faster than rock made from the same material. “So, during the day, sand will attain warmer temperatures faster—it has a low thermal inertia or resistance to temperature changes—while at night, rocks will be warmer because they cool off more slowly, that is, they have a higher thermal inertia,” Thomson said.
“The composition of the materials is well known, but their thermophysical response—how the materials respond to changes in temperature—is a new element of investigation into this otherwise well-studied target,” he said.
Studying impact craters on Earth and other planets is the main way planetary geoscientists determine the ages of landscapes off-planet. “Older surfaces tend to have more craters than younger surfaces,” Thomson explained.
The researchers were able to study only a small portion of the ejecta in this project, which served as a proof-of-concept. “This project would not have been possible without support from the UT student faculty research fund,” Thomson said. “We have submitted a follow-up proposal to NASA to study the whole crater in a similar manner.”
“This project is emblematic of the types of research that our department can produce when faculty work together collaboratively,” he said, noting it is also the type of research that undergraduates and graduate students at UT can participate in.
By Amy Beth Miller
