My research is primarily motivated by the desire to understand the properties and diversity of extrasolar planetary systems; I am particularly interested in finding out which nearby planetary systems are habitable for life.
Over the past decade I studied the formation, early evolution, and present-day properties of planetary systems and individual planets. My group is studying planetary systems in formation using the largest ground-based (MMT, VLT, LBT) and space-based telescopes (HST, Spitzer) telescopes to explore the atmospheric properties of exoplanets and brown dwarfs. We are pursuing the technique rotational mapping new to exoplanets, to characterize the photospheres and cloud properties in ultracool atmospheres. My group is also working on studies of forming planetary systems, aiming to identify the processes that influences the habitability of the emerging planetary systems.
Major Ongoing Projects:
EOS is a major, multi-insitutional astrobiology research team funded by the NASA Astrobiology program’s Nexus for Exoplanet System Science. The PI of the EOS Team is Daniel Apai and the University of Arizona is EOS’s lead institution. With over 25 investigators spanning five institutions, EOS is making a large, coordinated research effort toward the goal of understanding which nearby planetary systems are most likely to harbor earth-sized habitable-zone planets with the right inventory of biocritical ingredients.
In this program we monitor photometric and spectroscopy variations on a representative set of brown dwarfs on timescales ranging from hours to more than a year (1 to ~1,000 rotations). The targets vary in integrated light due to their rotation and their heterogeneous cloud covers. By comparing light curves at many different epochs, we can piece together the cloud cover evolution in the atmosphere and identify the fundamental physical and chemical process that drive those.
The program was awarded with 1,144 hours of Spitzer telescope time and 24 orbits of Hubble Space Telescope time.
Find out more about Extrasolar Storms.
In seven Hubble Space Telescope and six Spitzer Space Telescope programs we target brown dwarfs and use rotational modulations to explore the properties of their cloud covers as a function of their atmospheric parameters (temperature, rotation period, surface gravity, spectral type, colors).
We are also using high-contrast imagers (VLT/NACO, LBT/AO, HST, VLT/SPHERE) to obtain high-precisions lightcurves of planetary-mass or brown dwarf companions to nearby stars to determine their rotational periods and compare their cloud properties to those we observe in brown dwarf atmospheres.
ACCESS: The Arizona – CfA – Catholic Unversity Exoplanet Spectroscopy Survey
The ACCESS survey is the largest exiting ground-based spectroscopic study of transiting exoplanets. Led by Co-PIs Daniel Apai (U Arizona), Mercedes Lopez-Morales (Harvard-Smithsonian Center for Astrophysics), and Andres Jordan (Catholic University of Chile), this five year-long study is using the Magellan telescopes to build up the most comprehensive optical transmission spectral library of exoplanets, with masses ranging from super-earths through hot neptune and saturnes to hot jupiters.
Learn more about ACCESS.
High-Contrast Imaging: The MEPHISTO and Scorpion Surveys
The Mapping the distribution of Exoplanets with High-Contrast Imaging and Spectroscopy and the Scorpion Survey are powerful, adaptive optics-based high-contrast imaging surveys using VLT/NACO and VLT/SPHERE to image about 150 nearby young stars. The goal of the surveys is to determine the frequency of large-separation giant planets around them.
Our recent discoveries include a jovian planet in a triple stellar system and two new spatially resolved planet-forming disks.