{"id":73541,"date":"2024-12-12T11:02:04","date_gmt":"2024-12-12T18:02:04","guid":{"rendered":"https:\/\/in.nau.edu\/news\/?p=73541"},"modified":"2024-12-12T11:23:35","modified_gmt":"2024-12-12T18:23:35","slug":"hemmelgarn-comets","status":"publish","type":"post","link":"https:\/\/in.nau.edu\/news\/hemmelgarn-comets\/","title":{"rendered":"How to find a comet before it hits Earth"},"content":{"rendered":"

Q: How do you find a comet that could pose a threat to Earth but hasn\u2019t passed our planet in the last 200 years or more?<\/span>\u00a0<\/span><\/p>\n

A: You look for its footprint.<\/span>\u00a0<\/span><\/p>\n

This is the basis of research led by Samantha Hemmelgarn<\/strong>, a first-year doctoral student in Northern Arizona University\u2019s Department of Astronomy and Planetary Science. In a study published in <\/span>Planetary Science Journal<\/span><\/a> in November, she and her co-authors, including adviser Nick Moskovitz from Lowell Observatory, used data from meteor showers\u2014the \u201cfootprints\u201d left by comets\u2014to pinpoint where these comets are in the sky and determine whether they pose a threat to Earth.<\/span>\u00a0<\/span><\/p>\n

\u201cThis research gets us closer to defending Earth because it gives us a model to guide searches for these potentially hazardous objects,\u201d Hemmelgarn said.\u00a0<\/span>\u00a0<\/span><\/p>\n

The why and how of the research<\/span><\/b>\u00a0<\/span><\/h3>\n
\"Installing
Installing the Lowell Observatory Cameras for All-Sky Meteor Surveillance (LOCAMS) station in Holbrook in August 2023. Hemmelgarn worked on LOCAMS at Lowell Observatory, and the project contributes to the data used in this study. Top photo: An example of a meteor captured by a LOCAMS camera. Camera networks such as LOCAMS have been digitally observing meteors for the past ~15 years, constraining the orbits of meteor showers we can now use to simulate the orbits of the comets that left these streams behind.<\/em><\/figcaption><\/figure>\n

Historically, long-period comets, which have orbits of more than 200 years, have been virtually invisible to researchers until they get close to Earth and move toward the sun. The fear, of course, is that one will go undiscovered in the sky until it\u2019s too late and then hit the Earth. While the actual risk is incredibly small, Hemmelgarn said, the impact of even a small comet could be catastrophic to life on Earth, causing another Ice Age and ozone layer loss.<\/span>\u00a0<\/span><\/p>\n

So, they want to be proactive in identifying these comets. The researchers used a sample of 17 meteor showers they knew had long-period comet parents and created synthetic comets, which are models that represent where the parent comets could be in space based on the paths of those meteor showers. They compared the location of the real parent comets the last time they were near the sun to where the model predicted each comet would be. In most of the tests, the model accurately predicted a comet\u2019s location and helped predict the comet\u2019s direction and speed, which will help astronomers know where to find the real one with a telescope.<\/span>\u00a0<\/span><\/p>\n

This means researchers can find these comets in the sky before they get close to Earth.<\/span>\u00a0<\/span><\/p>\n

\u201cEven if the next extinction level impact is millions of years away, it\u2019s been fascinating to develop a model that traces the \u2018shooting stars\u2019 humans marvel at every night back to a region in space where we can discover the objects that left them behind,\u201d Hemmelgarn said.<\/span>\u00a0<\/span><\/p>\n

Her journey to this discovery<\/span><\/b>\u00a0<\/span><\/h3>\n

The day she graduated, Hemmelgarn would never have predicted that this exciting piece of the planetary defense puzzle would one day have her name on it.<\/span>\u00a0<\/span><\/p>\n

\"Samantha
Hemmelgarn and her family<\/em><\/figcaption><\/figure>\n

Of course, that\u2019s because she graduated with a degree in marketing and a job offer as assistant manager for Walgreens, where she did a management internship. For years, she thrived in that environment, employing her problem-solving skills to ensure her store stocked what her diverse customer base needed.<\/span>\u00a0<\/span><\/p>\n

However, with the advent of online retail, she found herself without the chance to solve problems and make decisions about her store. When she met her now-wife, Hayley, in 2019, Hemmelgarn realized she wanted something new.<\/span>\u00a0<\/span><\/p>\n

\u201cWhen I saw the passion and joy she exhibited for her career as a genomic epidemiologist, I realized that the same feeling I once had for retail management wasn\u2019t there anymore,\u201d she said. \u201cI always had a passing interest in astronomy, began researching how a person could make a career in that field and decided it was as good a time as any to change careers since I still have many working years ahead of me.\u201d<\/span>\u00a0<\/span><\/p>\n

In 2020, she started a bachelor\u2019s program in physics and astrophysics at NAU, which she finished a year ago, and in the fall, she began a doctoral degree. This is her first publication as first author.\u00a0<\/span>\u00a0<\/span><\/p>\n

What comes next<\/span><\/b>\u00a0<\/span><\/h3>\n

In the next phase of this work, Hemmelgarn and Moskovitz plan to apply this method to 247 long-period comet meteor showers with unknown parents. They\u2019ll use data from the Rubin Observatory\u2019s upcoming Legacy Survey of Space and Time (LSST) to find the faintest objects, which Hemmelgarn hopes will include some of these missing long-period comets.<\/span>\u00a0<\/span><\/p>\n

\"Northern<\/span><\/p>\n

Heidi Toth | NAU Communications
\n(928) 523-8737 | heidi.toth@nau.edu<\/a><\/span><\/p>\n

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Q: How do you find a comet that could pose a threat to Earth but hasn\u2019t passed our planet in the last 200 years or more?\u00a0 A: You look for its footprint.\u00a0 This is the basis of research led by Samantha Hemmelgarn, a first-year doctoral student in Northern Arizona University\u2019s Department of Astronomy and Planetary…<\/a><\/p>\n","protected":false},"author":59,"featured_media":73542,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[11],"tags":[],"class_list":["post-73541","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research-academics"],"acf":[],"_links":{"self":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts\/73541","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/users\/59"}],"replies":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/comments?post=73541"}],"version-history":[{"count":0,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts\/73541\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/media\/73542"}],"wp:attachment":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/media?parent=73541"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/categories?post=73541"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/tags?post=73541"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}