Astrogeologists

Geology is a young science, first developed by early mining engineers. In the late 18th century, scientists such as A. G. Werner and James Hutton, a retired British physician, created a sensation with their differing theories on the origins of rocks. Through the study of fossils and the development of geological maps, others continued to examine the history of the Earth in the 19th century.

From these beginnings, geology has made rapid advances, both in scope and knowledge. With the development of more intricate technology, geologists are able to study areas of the Earth they were previously unable to reach. Seismographs, for example, measure energy waves resulting from the Earth’s movement in order to determine the location and intensity of earthquakes. Seismic prospecting involves bouncing sound waves off buried rock layers.

The field of astrogeology developed along with America’s interest in space exploration and study. An astrogeologist named Gene Shoemaker founded the Astrogeology Research Program (ARP) in 1963, and he served as its first chief scientist. The ARP is now known as the Astrogeology Science Center (ASC). The ASC states that its mission is "to help humanity understand our solar system by maximizing the scientific and technological return from planetary missions through scientific research, software development, and the creation of spatial data products and standards."

Only 12 astronauts (including one geologist, Harrison Schmitt) have walked on and studied the surface of the Moon. Schmitt helped map the geology of the Moon and led the Lunar Field Geological Methods project. On December 11, 1972, Schmitt and another astronaut named Eugene Cernan stepped out of the lunar module, Challenger, and walked on the Moon. They collected rock samples, took photographs, and explored the surface of the Moon. They made several major discoveries, including that some of the soil on the Moon was orange and that the Moon once had a magnetic field.

Advances in technology and robotics are increasing research opportunities for astrogeologists. For example, they have used the Mars Exploration Rovers (e.g., Spirit Opportunity) to study the surface of Mars. The rovers have traversed the surface of Mars, taking photographs and scientific readings for study by astrogeologists and other scientists back on Earth. NASA's Perseverance Rover has been exploring the surface of Mars since February 2021. "The rover has made discoveries about the planet's volcanic history, climate, surface, interior, habitability, and the role of water in Jezero Crater," according to NASA.

These are exciting times for astrogeologists. In 2023, NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security–Regolith Explorer) returned with samples from the 4.5-billion-year-old asteroid Bennu. Scientists determined that the samples contain carbon, water, and other compounds. In coming years, NASA plans to send astronauts to asteroids, the Moon, and Mars. Perhaps an astrogeologist will be one of the astronauts selected for these journeys of discovery.