Impact Craters on the Moon: Making Craters in the Laboratory
Abstract
Impact cratering is the dominant geological process affecting all planetary surfaces throughout the solar system. Impact craters form when an asteroid crashes at high speeds into a planetary surface. Here on Earth, some notable impact craters are Barringer Crater in Arizona, the Chicxulub Crater in Mexico (which was responsible for the extinction of the dinosaurs), and the Manicouagan Impact Crater in Canada (one of the largest on Earth). Unfortunately, plate tectonics, biology, and erosion destroy impact craters on the Earth. However, impact craters are well preserved on the Moon, the Earth's dance partner in space. One of the ways we can study the formation of impact craters is through experiments. I am one of Dr. Jennifer Anderson's research assistants in her Experimental Impact Cratering research group. We use the Vertical Impact Facility at NASA Johnson Space Center's Experimental Impact Laboratory in Houston Texas to fire projectiles at high speeds into targets that we have created to mimic the Moon's surface. Our research question is to see how crater morphology changes from "normal" bowl-shaped craters if we add a stronger layer beneath a particulate layer. In the lunar mare, ancient lava flows covered the Moon's surface and have since been broken up into what we call a regolith. We use sand to model the regolith layer and a synthetic sandstone block to simulate the buried lava flow. We fire 4-mm Aluminum spheres at 1.5 km/s (3400 mph) in a vacuum similar to the environment on the Moon into these targets and use various camera systems to watch how the craters form. We also use a handheld 3D scanner to scan the final crater topography. Our control crater is formed into a bucket of sand only and then we completed a series of experiments into layered targets where the regolith layer is varied from 6-cm to 0-cm in thickness. We examined how the sand grains were ejected from the crater as it grows and also how the final crater topography changed as the regolith layer got thinner. In my poster presentation I will discuss the software programs that I used to investigate the ejecta kinematics and crater topography. In general, as the regolith layer got thinner, the crater morphology changed from bowl-shaped to flat-floored to concentric craters. The ejecta for the regolith-only crater is very well behaved while the ejecta for the thinner regolith experiments was much more complex. Our results have implications for understanding the substrate in the lunar mare regions.
College
College of Science & Engineering
Department
Geoscience
Campus
Winona
First Advisor/Mentor
Jennifer Anderson
Start Date
4-19-2023 9:00 AM
End Date
4-19-2023 10:00 AM
Presentation Type
Poster Session
Format of Presentation or Performance
In-Person
Session
1a=9am-10am
Poster Number
4
Impact Craters on the Moon: Making Craters in the Laboratory
Impact cratering is the dominant geological process affecting all planetary surfaces throughout the solar system. Impact craters form when an asteroid crashes at high speeds into a planetary surface. Here on Earth, some notable impact craters are Barringer Crater in Arizona, the Chicxulub Crater in Mexico (which was responsible for the extinction of the dinosaurs), and the Manicouagan Impact Crater in Canada (one of the largest on Earth). Unfortunately, plate tectonics, biology, and erosion destroy impact craters on the Earth. However, impact craters are well preserved on the Moon, the Earth's dance partner in space. One of the ways we can study the formation of impact craters is through experiments. I am one of Dr. Jennifer Anderson's research assistants in her Experimental Impact Cratering research group. We use the Vertical Impact Facility at NASA Johnson Space Center's Experimental Impact Laboratory in Houston Texas to fire projectiles at high speeds into targets that we have created to mimic the Moon's surface. Our research question is to see how crater morphology changes from "normal" bowl-shaped craters if we add a stronger layer beneath a particulate layer. In the lunar mare, ancient lava flows covered the Moon's surface and have since been broken up into what we call a regolith. We use sand to model the regolith layer and a synthetic sandstone block to simulate the buried lava flow. We fire 4-mm Aluminum spheres at 1.5 km/s (3400 mph) in a vacuum similar to the environment on the Moon into these targets and use various camera systems to watch how the craters form. We also use a handheld 3D scanner to scan the final crater topography. Our control crater is formed into a bucket of sand only and then we completed a series of experiments into layered targets where the regolith layer is varied from 6-cm to 0-cm in thickness. We examined how the sand grains were ejected from the crater as it grows and also how the final crater topography changed as the regolith layer got thinner. In my poster presentation I will discuss the software programs that I used to investigate the ejecta kinematics and crater topography. In general, as the regolith layer got thinner, the crater morphology changed from bowl-shaped to flat-floored to concentric craters. The ejecta for the regolith-only crater is very well behaved while the ejecta for the thinner regolith experiments was much more complex. Our results have implications for understanding the substrate in the lunar mare regions.
