Scientists and researchers have long studied meteorites – the masses of rock-like space material that falls through the Earth’s atmosphere to land on our planet. However, these samples have been altered by their journey through the atmosphere and contaminated by organisms once they reach Earth.
It is much more difficult to collect and study unaltered, uncontaminated samples of meteoroids and asteroids from space.
Mike Callahan, an assistant professor in the Department of Chemistry and Biochemistry, has been awarded a two-year, $446,413 grant to develop analytical techniques to analyze the organic composition of material collected in space during NASA missions. Callahan’s research is being funded by the NASA Laboratory Analysis of Returned Samples (LARS) program.
“We will be developing analytical methods to look for biologically relevant organic molecules in extraterrestrial materials. A big focus will be looking for nitrogen heterocyclic compounds and nucleobases,” Callahan said. Nucleobases are compounds that serve as the structural basis of information storage in RNA and DNA and are believed to have been essential for the origin of life. Nucleobases are found in all living organisms – they are also required by many protein enzymes to catalyze reactions.
“Since these nucleobases are essential to all known life, they would seem important in how life developed. The intriguing part is that we believe these organic molecules were made in space inside asteroids, which happened billions of years ago. And meteorites were a vehicle to bring these organic molecules to an early Earth,” Callahan added.
Another goal of the project is to reduce the sample requirements needed to conduct a thorough asteroid analysis for two current missions: a trip to collect samples from the asteroid Ryugu by JAXA, the Japanese Space Agency, which is expected to return to Earth in December 2020, and a NASA mission called OSIRIS-REx to collect samples from the asteroid Bennu, which is expected to be completed in September 2023.
“We want to reduce the mass requirements needed for these samples because they’re so precious and unique,” Callahan explained. His team will test their analytical methods on meteorites collected from Antarctica, which are expected to be representative of these asteroid samples.
The grant also will allow Callahan to buy a mass spectrometer for his laboratory. The mass spectrometer measures the mass-to-charge ratio of organic molecules, allowing researchers to help identify organic compounds and understand how much is there.
“Samples from space missions have come a long way. To develop the tools that give us a way to peek inside, that’s very exciting for us. And we are very fortunate to have NASA support our research,” Callahan said.