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The distribution of neutrons with energies below 15 MeV in spherical stony meteoroids is calculated using the ANISN neutron‐transport code. The source distributions and intensities of neutrons are calculated using cross sections for the production of tritium. The meteoroid's radius and chemical composition strongly influence the total neutron flux and the neutron energy spectrum, whereas the location within a meteoroid only affects the relative neutron intensities. Meteoroids must have radii of more than 50 g/cm2 before they have appreciable fluxes of neutrons near thermal energies. Meteoroids with high hydrogen or low iron contents can thermalize neutrons better than chondrites can. Rates for the production of 60Co, 59Ni, and 36Cl are calculated with these neutron fluxes and evaluated neutron‐capture cross sections and are reported for carbonaceous chondrites with high hydrogen contents, L‐chondrites, and aubrites. For most meteoroids with radii <300 g/cm2, the production rates of these neutron‐capture nuclides increase monotonically with depth. The highest calculated 60Co production rate in an ordinary chondrite is 375 atoms/min/g‐Co at the center of a meteoroid with a 250 g/cm2 radius. The production rates calculated for spallogenic 60Co and 59Ni are greater than the neutron‐capture rates for radii less than ∼50–75 g/cm2. Only for very large meteorpids and chlorine‐rich samples is the neutron‐capture production of 36Cl important. The results of these calculations are compared with those of previous calculations and with measured activities in many meteorites.

PyMOL is a molecular modeling program that can be used in a wide range of studies within the scientific community. Its ability to produce informative, detailed, stereoscopic images makes it a very powerful tool both in the laboratory and in the classroom. However, the PyMOL user interface is difficult to use, and the PyMOL User's Manual readily admits that "development has been focused on capabilities, not on easeof-use for new users." To resolve this, we set out to develop a new interface for PyMOL that helps eliminate the need for command line interactions, making it a much more user-friendly interface. We have created a tabbed interface called EZ-Viz, which contains a series of buttons and entry fields that allow users to select given attributes of a molecule and make changes to it by clicking a button as opposed to issuing highly syntactical commands. Other features of the interface include a Chime/PyMOL command converter, nine preset molecular views, four molecular movies, and molecular sequence and hetero atom information, all at the click of a button. The ongoing and continued development of EZ-Viz could help to further the use of PyMOL, which we believe to be one of the most powerful molecular viewing programs currently available.