How does one go about detecting a comet that hasn’t passed near Earth in over 200 years?

The answer might just lie in the cosmic footprints these comets leave behind!

This groundbreaking approach is spearheaded by Samantha Hemmelgarn, a passionate first-year doctoral student at Northern Arizona University’s Department of Astronomy and Planetary Science. Her research, published in The Planetary Science Journal last November, leverages data obtained from meteor showers—essentially the cosmic breadcrumbs left by comets—to track their locations and assess potential risks to our planet.

According to Hemmelgarn, this research inches us closer to developing a reliable defense against such cosmic threats. “It's all about creating a model that can help us search for these potentially hazardous objects,” she explained.

The Drive Behind the Research

Long-period comets are notorious for their elusive nature; their vast orbits mean they can remain undetected until they approach the sun and Earth. The fear that one might go undetected until it's too late is a real concern. Although the likelihood of a comet causing significant harm is minimal, Hemmelgarn emphasizes that even a small impact could have catastrophic results, potentially triggering an Ice Age or leading to severe ozone depletion.

To mitigate this risk, her research team focused on 17 meteor showers known to be associated with long-period comets, producing synthetic models that simulate where these parent comets might be lurking in the cosmos. By comparing the locations of real comets from their last solar visit with model predictions, the researchers successfully identified comet positions and trajectories—paving the way for future discoveries using telescopes.

“We may have millions of years until the next extinction-level event, but the model we’re developing traces the 'shooting stars' that captivate human imagination back to the regions in space where we can possibly discover their origins,” Hemmelgarn noted.

A Serendipitous Journey

In an unexpected twist, Hemmelgarn's journey to becoming a in-demand researcher began far from the stars. After graduating with a marketing degree and managing a Walgreens store, her life took a dramatic turn. As the retail landscape began to shift, she found herself yearning for a career that would reignite her passion. After meeting her now-wife, Hayley, a genomic epidemiologist, Hemmelgarn made a bold change, determined to follow her long-held interest in astronomy.

In 2020, she embarked on a new path, completing a bachelor's degree in physics and astrophysics and recently moving into a doctoral program. Her latest publication marks a significant milestone as her first authorship.

What’s Next?

Looking ahead, Hemmelgarn and her adviser, Nick Moskovitz, plan to broaden their research by applying the same innovative model to 247 meteor showers linked to unknown long-period comets. They will utilize data from the upcoming Legacy Survey of Space and Time (LSST) being conducted at the Rubin Observatory, aiming to identify even the faintest cosmic characters that are currently missing from the astronomical maps.

Could these revelations eventually shield Earth from impending comet dangers? Only time will tell, but one thing is certain: Hemmelgarn’s journey from marketing to planetary defense is just beginning, and the stars may hold the key to Earth's safety!

Stay tuned, as we keep an eye on groundbreaking discoveries that could change the way we think about our cosmic neighbors and their potential threats.