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Erin C Smith

Publications and source records attributed to Erin C Smith.

Status of the James Webb Space Telescope Mission

The James Webb Space Telescope ( Webb) is the largest space telescope realized to-date, with a 6.5 m segmented primary mirror that must be folded to fit within its Ariane 5 launcher fairing. This infrared telescope is passively cooled using a five-layer sunshield that will keep the optical telescope and its four science instruments in the shade throughout the lifetime of the mission in an L2 orbit. Webb's science instruments include near- and mid­ infrared imagers and spectrometers that cover the spectral range from 0.6-28.5 µm. The Webb mission has a long history with numerous first of its kind technology developments, ground support equipment innovations, and algorithmic characterization advances. This conference proceeding summarizes the technical progress over the past two years, from the Spacecraft Element environmental testing to the Observatory integration and testing, and the final Observatory test plans leading up to launch, on-orbit commissioning, and science operations.

Michael W McElwain↗

SOFIA/FLITECAM 3-5.4 Micron Spectroscopy of PAHs in Planetary Nebulae

We present stratospheric observations of the ~3-5.4 micron spectra of young planetary nebulae by the SOFIA instrument FLITECAM. The goal of this study was to characterize the NIR emission of Polycyclic Aromatic Hydrocarbons (PAHs) in planetary nebulae and study the evolution of PAH features within these objects. Using airborne 3-5.4 micron grism spectroscopy of three young, Carbon-rich planetary nebulae: IC 5117, PNG 093.9-00.1, and BD +30 3639, we investigated the spectral variation of the 3.3 micron PAH feature, its associated aliphatic features (3.4-3.6 microns), characterized the weak 5.25 PAH emission feature, and set limits on the theoretical contribution of the 4.4-4.8 micron deuterated-PAH features. All features, including atomic emission lines, were fit with a series of Gaussians to determine their flux. We further characterized the 3.3 micron PAH feature using equivalent width and central wavelength, and classified the shape of the emission. We also determined the PAH/Aliphatic ratio for each target. The 3.3 micron PAH emission feature is observed in all three objects, as is PAH emission at 5.25 microns. PNG 093.9-00.1 exhibits NGC 7027-like aliphatic emission in the 3.4–3.6 micron region while aliphatic emission in IC 5117 and BD +30 3639 is weaker, and exhibits less structure.

Erin C Smith↗

Preparing the JWST Observatory for Science Observations

The James Webb Space Telescope (JWST) is a large (6.5 m) near-and mid-infrared telescope scheduled for launch in 2021. JWST will be used to explore fundamental questions in astrophysics and planetary science, including the evolution of galaxies, the first light of stars, the formation of stars and planets as well as the characterization of exoplanets. To achieve these scientific goals, NASA and its international partners, the Canadian Space Agency (CSA) and the European Space Agency (ESA), have developed four science instruments for JWST and have prepared detailed commissioning plans for each. The NASA Project Science team has also outlined activities to characterize the performance of the Observatory as a whole. These activities include: 1) monitoring of the instrument and telescope cooldown for contamination mitigation; 2) measurements of straylight and other backgrounds for validation of the JWST stray light models as well as instrument background subtraction algorithms; 3) characterization of optical thermal distortion between its hot and cold telescope pointings within the observable field of regard and 4) trending of observatory performance parameters. Each of these activities has been planned in close collaboration with the observatory wavefront, commissioning planning, and science instrument teams. Here we present the plans for these activities, the expected results and how they will impact future guest observer (GO) proposals and JWST science community

Erin C Smith↗