Helping NASA Sample an Asteroid
by AMNH on
If you’re a geologist, says Harold Connolly, a research associate in the Museum’s Department of Earth and Planetary Sciences, ordinary rocks can contain a staggering amount of information.
“Rocks are books. The pages are minerals. They tell us a story—how they were formed, where they were formed, what’s happened to them since,” Dr. Connolly says.
The next rock Connolly will be studying, though, is far from ordinary. In fact, it’s out of this world. In addition to his work at the Museum and Rowan University, Connolly is working with NASA to oversee the analysis of samples for OSIRIS-REx—the first U.S. mission to gather material from an asteroid, and one that you can follow online.
If the mission, launched this September, goes according to plan, the NASA spacecraft will arrive at the asteroid Bennu in 2018, then spend a year and a half photographing and mapping this massive space rock.
Once a site is selected, a robotic arm will touch down on the surface to gather soil samples in the course of just a few seconds. The yearlong mapping is essential to selecting the site, after which the spacecraft will have up to three tries to retrieve at least 2.1 ounces (60 grams) or up to 4.4 pounds (2 kilograms) of samples that may hold invaluable insights into our solar system and the emergence of life on Earth.
Only in September 2023 will the work of studying the samples back on Earth begin, after a return capsule touches down in Utah. Connolly isn’t daunted by the wait. “It’s what the process of exploring is about,” he says.
Bennu is of particular interest to scientists because it has a high probability of crashing into Earth in the late 22nd century, and better understanding its nature is critical to possibly deflecting it. It is also a rare type-B asteroid, carbon-rich and composed of materials relatively unchanged since it formed more than 4.5 billion years ago. Researchers hope that surface samples will contain prebiotic organic compounds that can offer clues about the formation of our solar system, as well as the origins of life on Earth.
Since the technology used to study the samples—CT scanning, electron beam imaging, mass spectrometry—is developing at a fast clip, the duration of the mission means scientists will have even better tools by the time Bennu specimens arrive on Earth.
“Already, the ability to look at really small things is astonishing,” says Curator Denton Ebel, who analyzes the makeup of meteorites, pieces of asteroids that have landed on Earth. “We can look at presolar grains, truly stardust, found in meteorites.”
A version of this story originally appeared in the Fall 2016 issue of Rotunda, the Member magazine.