The Science

The Science of the Astrophysics & Astrochemistry Laboratory

The Astrophysics & Astrochemistry Laboratory uses innovative techniques to study the physics and the chemistry of gas phase molecules and solids in various environments in the universe that range from interstellar galactic environments (dense and diffuse clouds) to cometary and planetary environments (atmospheres and surface ices) to the lunar surface (lunar dust).

The major areas of active research of the Astrophysics & Astrochemistry Laboratory are focused on questions relevant to the fields of astrophysics, astrochemistry and astrobiology.


The Cosmic Complexity of Carbon: Polycyclic Aromatic Hydrocarbons (PAHs)

The simplest aromatic hydrocarbon is the famous benzene molecule which consists of six carbon atoms and six hydrogen atoms as shown in figure 1. The six carbon atoms are bound into a closed, planar ring with the carbon atoms sitting on the vertices of a hexagon. Each carbon atom is further bound to a single hydrogen atom which lies exterior to the central ring. The aromatic character of the molecule, in practical terms, refers to the fact that the benzene molecule's ring-shaped structure makes its carbon-carbon skeleton more stable when compared to other types of hydrocarbon molecules. More...

amino acid

Amino Acids and Their Production during the Photolysis of Astrophysically relevant Ices

Amino acids are important biological molecules that serve as the basic molecular building blocks of proteins and enzymes used by all living things on Earth. All amino acids have a similar basic structure like that below, with different amino acids differing only in the specific structure that lies in the location labeled with the “R”. More...

bilayer vesicle

Amphiphiles – A Major Photoproduct of the UV Irradiation of Interstellar Ices

Amphiphiles are long molecules that have a polar, hydrophilic (water-loving) head group and a hydrophobic (water-fearing) tail. Molecules of this sort are common in detergents – in the presence of dirt they will orient themselves to surround the particles with their tails on the particle (away from the water) and their heads facing outward (into the water). This effectively couples the particle to the surrounding water and makes it easier to wash away. More...


Hexamethylenetetramine (HMT) – A Major Photoproduct of the UV Irradiation of Interstellar Ices

Hexamethylenetetramine (HMT), C6H12N4 was identified as a compound over 130 years ago. It was the first organic molecule on which X-ray crystallography was performed and it was found to have tetrahedral symmetry. The infrared (IR) and Raman spectra of the solid and infrared spectra of the gas have been reported and the small number of observed fundamentals is in accord with the high degree of symmetry of this molecule. More...


Simulating Low Temperature Photochemistry in Space - The Photoproduction of Organic Residues in Laboratory Interstellar Ice Analogs

New stars and planets form in dense interstellar molecular clouds. These clouds are sufficiently dense to screen out outside starlight and the dust grains in them can get as cold as 10 K (-263 oC). At these temperatures, most gas phase materials other than hydrogen, helium, and neon, will freeze out onto these cold dust grains, much as the water vapor in your breath freezes onto a cold window. As a result, most of the grains in dense clouds are coated with a mantle of ice that contains a variety of molecules. More...


Nucleobases and Their Production during the Photolysis of Astrophysically-relevant Ices

DNA (deoxyribonucleic acid) and RNA (ribonucleic cid) play fundamental roles in carrying genetic information in all living things on Earth. These structures are double helixes that look like a twisted ladder in which the rungs of the ladder consist of match pairs of nucleobases. There are a total 5 nucleobases in DNA and RNA. They are Cytosine, Guanine, Adenine (which can be found in DNA and RNA), Thymine (found only in DNA), and Uracil (found only in RNA). In DNA, adenine pairs with thymine and cytosine pairs with guanine. In RNA, the adenine pairs with uracil rather than with thymine. More...


PAH-related photoproducts (alcohols, ketones, Hn-PAHs, and other substituted aromatic systems)

Polycyclic aromatic hydrocarbons (PAHs) represent one of the most abundant forms of carbon in the universe. They are seen in a wide variety of environments in space, and many varieties of these molecules are seen in meteorites as well as asteroidal and cometary dust. Traditional PAHs consist of fused groups of six-sided carbon rings laid out in a planar structure. The figure below shows some examples of PAHs containing different numbers and arrangements of rings, although the possible arrangement or rings is enormous. In the structures in the image below, each vertex represents a carbon atom. A single hydrogen atom is attached to each external vertex. More...