Vertical structure of an exoplanet's atmospheric jet stream.

Ultra-hot Jupiters, an extreme class of planets not found in our solar system, provide a unique window into atmospheric processes. The extreme temperature contrasts between their day- and night-sides pose a fundamental climate puzzle: how is energy distributed? To address this, we must observe the 3D structure of these atmospheres, particularly their vertical circulation patterns, which can serve as a testbed for advanced Global Circulation Models (GCM) e.g.

Self-Oxidation of the Atmospheres of Rocky Planets with Implications for the Origin of Life.

Rocky planets may acquire a primordial atmosphere by the outgassing of volatiles from their magma ocean. The distribution of O between HO, CO, and CO in chemical equilibrium subsequently changes significantly with decreasing temperature. We consider here two chemical models: one where CH and NH are assumed to be irrevocably destroyed by photolysis and second where these molecules persist.

Vanadium oxide and a sharp onset of cold-trapping on a giant exoplanet.

The abundance of refractory elements in giant planets can provide key insights into their formation histories. Owing to the low temperatures of the Solar System giants, refractory elements condense below the cloud deck, limiting sensing capabilities to only highly volatile elements. Recently, ultra-hot giant exoplanets have allowed for some refractory elements to be measured, showing abundances broadly consistent with the solar nebula with titanium probably condensed out of the photosphere.

The CO-rich atmosphere of a young accreting super-Jupiter.

Isotope abundance ratios have an important role in astronomy and planetary sciences, providing insights into the origin and evolution of the Solar System, interstellar chemistry and stellar nucleosynthesis. In contrast to deuterium/hydrogen ratios, carbon isotope ratios are found to be roughly constant (around 89) in the Solar System, but do vary on galactic scales with a C/C isotopologue ratio of around 68 in the current local interstellar medium. In molecular clouds and protoplanetary disks, CO/CO ratios can be altered by ice and gas partitioning, low-temperature isotopic ion-exchange reactions and isotope-selective photodissociation.

LOUPE: observing Earth from the Moon to prepare for detecting life on Earth-like exoplanets.

LOUPE, the Lunar Observatory for Unresolved Polarimetry of the Earth, is a small, robust spectro-polarimeter for observing the Earth as an exoplanet. Detecting Earth-like planets in stellar habitable zones is one of the key challenges of modern exoplanetary science. Characterizing such planets and searching for traces of life requires the direct detection of their signals.

Design trade-off and proof of concept for LOUPE, the Lunar Observatory for Unresolved Polarimetry of Earth.

We provide a proof of the technical feasibility of LOUPE, the first integral-field snapshot spectropolarimeter, designed to monitor the reflected flux and polarization spectrum of Earth. These are to be used as benchmark data for the retrieval of biomarkers and atmospheric and surface characteristics from future direct observations of exoplanets. We perform a design trade-off for an implementation in which LOUPE performs snapshot integral-field spectropolarimetry at visible wavelengths.

Aerosol deposition in the upper airways of a child.

In a small child, normally only a small amount of inhaled aerosol particles reaches the lungs because the majority deposits in the upper airways. In this study, the upper airways of a 9- month-old child, based on computed tomography (CT) data, are modeled to serve as input for a computational fluid dynamics package (CFX). Verification of the validity of aerosol deposition calculations by this package is accomplished by evaluating two test cases, which also can be solved analytically.