Andrew Mann

The Young Worlds Team:

Mackenna Wood

Mackenna is a third-year graduate student in the in the Department of Physics and Astronomy. She works on measuring ages of known and newly identified young stellar associations near the Sun using a variety of methods, including lithium abundances (the lithium depletion boundary). This includes work identifying low-mass members of existing young stellar associations.

Mackenna also works on placing robust limits on unseen stellar companions to planet hosts from the K2 and TESS missions. Her framework has already been used to aid with exoplanet validation (e.g., Rizzuto et al 2020 and Mann et al. 2020).

You can learn more about Mackenna's work at her website.


Pa Chia Thao

Pa Chia is a second-year graduate student in the in the Department of Physics and Astronomy. Her research focuses on characterizing atmospheres of young planets through their transit depth as a function of wavelength (transmission spectroscopy). The greater goal is to study how planetary atmospheres change with time by comparing the transmission spectra of young planets to their older counterparts.

The figure on the right shows transits of the 700 million-year-old planet, K2-25b, taken with (top to bottom) K2, LCO, MEarth, and two Spitzer bands. The K2 transit appears 'smoother' because of the long integration time (30m) compared to the other datasets (3 minutes or lower). The difference in transit depth over these wavelengths tells us about the overall properties of the planet. More on these observations can be found in Thao et al. (2020).

Pa Chia's dog, Wally, is a major contributor to her scientific productivity, but needs to work on his organization skills.



Reilly Milburn

Reilly is a second-year graduate student in the in the Department of Physics and Astronomy. He is interested in young exoplanets and stellar systems. His current work focuses on the detection of the extended atmospheres (exospheres) of young planets using transmission spectroscopy in regions related to atmospheric escape (e.g., Hα and He10830). The greater goal is to understand how planets lose their atmospheres as they evolve (e.g., photoevaporation).

When Reilly is not poring through data, he likes to play guitar, shoot photography, and play tabletop games with friends.


Madyson Barber

Madyson is a junior undergraduate majoring in Computer Science and Astrophysics. Her research focuses on building automated querying processes for rapid characterizing of newly identified planets (and their host stars) from the TESS mission. She also works on vetting light curves of transiting planet candidates to separate out false positives (e.g., binary stars) from true planets.

Madyson is a Chancellor's Science Scholar, and spent the Summer of 2020 as a NASA GSFC Summer Intern.

Madyson's dog, Halee, loves running around Blue Jay Point, but has trouble with python.


Dylan Owens

Dylan is a senior undergraduate majoring in Astrophysics. His current research focuses on determining the orbital eccentricities of young (<1000 Myr) transiting planets using data primarily from the K2 and TESS missions. The goal of the project is to compare the eccentricities of young planets to their older counterparts, testing the hypothesis that planets are born in chaotic, highly eccentric orbits that dampen over time into more circular ones.

Dylan's dog, Biscuit, is the coolest dog in the outer banks, but he still doesn't understand how MCMC works.

The figure on the right shows the eccentricity posterior for the young planet K2-25. This is estimated from the K2 photometry of the planet and an estimate of the stellar density.



Matthew Fields

Matt is a second-year graduate student in the Department of Physics and Astronomy. His research interests include both observational and computational astronomy, particularly on stars and planets. He is also interested in science policy, science education, and science communication. Currently, Matt works on deriving improved radii of young stars with protoplanetary disks using a combination of stellar models and semi-empirical relations. The goal is to understand how often planet-forming disks (and hence the young planets they form) are aligned with the rotational spin of their host stars.

Matt's cats, Dudley (left) and Maizie (right) often contribute to group meetings, but really struggle with error propagation.


Jonathan Bush

Jonathan is a second year graduate student in the Department of Physics and Astronomy. His research focuses on measuring the rotation periods of stars (stellar variability), which are used as a proxy for the age of the star. Jonathan makes use of TESSand K2 light curves processed to preserve stellar variability. The greater goal is to identify (and confirm) new members of young associations and constrain the age of planets identified both in these associations and in the young field population.

The figure to the right shows the rotation period versus color sequence of Praesepe (700 Myr), Pleiades (125 Myr), and Ursa Major (400 Myr) groups. Jonathan is using these squences to aid in his search for young stars and planets.

Jonathan's dogs, Jojo (left) and Sonni (right), regularly assist with extracting rotation periods, but often find period aliases by accident.



Stephen Schmidt

Stephen is a junior undergraduate majoring in Astrophysics and Applied Mathematics. His research focuses on measuring the metallicities of M dwarfs from Gaia photometry and distances, calibrated using wide binaries containing a Sun-like primary and an M dwarf companion.

He has also worked on a photometry reduction pipeline for LCO follow-up of young eclipsing binaries and transiting exoplanets, which you can read more about in his astrobites article.