Research

Near-Sun Asteroids

Many comets and asteroids spend part of their dynamical lifetimes with small perihelion distances (or "low-q'') as a result of dynamical interactions with Jupiter. However, there are fewer such asteroids observed than are predicted by dynamical models, attributed to near-complete disintegration when an asteroid reachs a perihelion distance q < 0.076 au. I am studying asteroids that come close to the Sun to search for signs of near-Sun processes on the surface that might lead to disruption. We have successfully observed the majority of asteroids with a q <0.15 au. We found that interacting processes and varying orbital histories create a wide range of colors. However, a slight preference to bluer colors indicates that resurfacing mechanisms could be dominant (e.g. thermal fatigue).

Dynamically New Comets

Objects that enter the inner Solar System from the Oort cloud for the first time since they were emplaced there millions of years ago are called dynamically new comets (DNCs). Because objects in the Oort cloud cannot be observed directly, we must rely on observations of dynamically new comets to understand the properties of the Oort cloud. Therefore, observations of DNCs allow us to study objects nearly unchanged since their formation (unlike Jupiter Family, Halley-type, or returning long-period comets). I am characterizing the brightness behavior of DNCs using archival data from surveys to span a large observing arc. We expect these objects to behave differently from other comets because they have yet to build up a dust mantle.



Outreach

GRAD-MAP

I am involved with GRAD-MAP (Graduate Resources Advancing Diversity with Maryland Astronomy and Physics), which pairs undergraduates from historically black colleges and universities, minority serving institutions, and community colleges primarily from the mid-Atlantic region with a mentor in either the UMD astronomy or physics departments. During the winter break, these students attend a ten-day Winter Workshop, where they learn Python, work on a research project, and learn information and resources to help them apply for graduate school. I have developed a student project, served as a research mentor, and also assisted with some of the professional development during the Winter Workshop.

Skype a Scientist

Growing up in South Carolina, I thought all scientists wore labcoats and I did not meet one until I went to college. This is just one reason why I believe volunteering with Skype a Scientist, which connects scientists to classrooms around the world, to be so important. I have been volunteering as a scientist since the beginning of the COVID-19 pandemic talking to classrooms about asteroids, planetary defense, and what it is like to be an astronomer.

Contact

Mailing Address:
Department of Astronomy
University of Maryland
1113 PSC Bldg. 415
College Park, MD 20742

Office: ATL 1227

carrieholt@astro.umd.edu