Hi! My name is Isabel McIntyre, and I am a recent graduate of Mount Holyoke College where I double majored in astronomy and biological sciences, and a soon-to-be Astrophysics PhD student at Arizona State University. At school, my research is on galaxy evolution, but this summer I have been shifting gears to work on a problem important in both astronomy and biology: light pollution.

The Milky Way and Stars above the LBJ Ranch. The silhouette of a pole and trees can be seen near the bottom of the image, and an orange glow is present on the horizon.
The Milky Way over the LBJ Ranch. The orange glow on the horizon is light pollution from a nearby town, but despite this, the night skies here are still incredibly dark. (Photo credit: Isabel McIntyre)

When many people hear that I studied both astronomy and biology, they assume that I study astrobiology, or the study of life beyond Earth and the origins of life. As interesting as astrobiology is, it is not the only intersection between astronomy and biology! Light pollution most noticeably affects our ability to see the stars, which can prevent astronomers from collecting necessary data, but also makes it harder for people to access dark skies to view the stars under. But did you know that some birds need the stars to use as a guide during migration? Or that artificial light alters the behavioral patterns of many nocturnal species? The issue of light pollution is one that is far reaching and must be addressed. This is where my project comes in.

A nine-banded armadillo facing away from the camera. It is walking in the grass next to the side of a brown building.
A nine-banded armadillo, one of the many nocturnal species that can be found at the LBJ Ranch. (Photo credit: Isabel McIntyre)

The Lyndon B. Johnson National Historical Park, where I am located, is split into two districts: the Johnson Settlement in Johnson City, Texas, and the LBJ Ranch in Stonewall, Texas. Both districts are home to many historical sites, including Lyndon B. Johnson’s boyhood home in Johnson City, and his birthplace and the Texas White House at the LBJ Ranch. The LBJ Ranch is also an International Dark-Sky Association (IDA) certified Dark Sky Park, meaning that it is recognized for having incredibly dark skies! A lot of work went into getting the LBJ Ranch certified as a Dark Sky Park, and there’s still plenty of work to maintain this certification.

As part of my internship, I am cataloging all of the outdoor lighting at the LBJ Ranch and assessing if it is compliant with IDA regulations. Then, I am able to make recommendations for how to retrofit lights that aren’t compliant. This presents a particularly interesting challenge at a historical park, because we need to preserve the historical fixtures around the park.

Isabel, wearing a green SIP t-shirt and baseball cap, stands smiling to the left of the image, in front of the Texas White House. The Texas White House is a large, two-story white building, with a hedge in front of it.
Isabel outside the Texas White House, while assessing the lights on and around the building for IDA compliance. (Photo credit: Isabel McIntyre)

I am also responsible for taking sky quality meter readings to measure how dark the skies around the LBJ Ranch are. This is one of my favorite parts of my job, because it is when I get to drive around the Ranch at night, see the incredible stars, and collect data! This data is also used to maintain our Dark Sky Park certification, and it is an excellent way to track the light pollution at the LBJ Ranch over time.

The silhouette of a person with an arm raised and the silhouette of trees. There are stars overhead.
Isabel taking a measurement using the sky quality meter. (Photo credit: Isabel McIntyre)

Through my work, I’m also planning several events for the community. This includes a watch party for the James Webb Space Telescope’s first science image release this summer and a night hike, where I will take visitors around the Johnson Settlement and talk to them about astronomy and the importance of dark skies for local flora and fauna. Events like the night hike can be repeated and will allow for this knowledge to be shared with the  community even after the end of my internship.

It’s hard to believe it’s been over a month since I arrived at the park, but I’ve enjoyed every second of it. Stay tuned for more on my work as the summer progresses, and I wish you all clear skies!

Published by Isabel McIntyre

Isabel is a Scientists in Parks Fellow located at the Lyndon B. Johnson National Historical Park. They graduated from Mount Holyoke College with a bachelor's degree in Astronomy and Biological Sciences, and will be continuing their studies this fall at Arizona State University in the Astrophysics PhD program, focusing on galaxy formation and evolution. In their free time, Isabel loves music (and is learning guitar and banjo) and dance.