Thermal infrared emissivity measurements under a simulated lunar environment: Application to the Diviner Lunar Radiometer Experiment

Journal of Geophysical Research: Planets 117:1 (2012)

Authors:

KL Donaldson Hanna, MB Wyatt, IR Thomas, NE Bowles, BT Greenhagen, A Maturilli, J Helbert, DA Paige

Abstract:

We present new laboratory thermal infrared emissivity spectra of the major silicate minerals identified on the Moon measured under lunar environmental conditions and evaluate their application to lunar remote sensing data sets. Thermal infrared spectral changes between ambient and lunar environmental conditions are characterized for the first time over the 400∼1700 cm -1 (6-25 m) spectral range for a fine-particulate mineral suite including plagioclase (albite and anorthite), pyroxene (enstatite and augite), and olivine (forsterite). The lunar environment introduces observable effects in thermal infrared emissivity spectra of fine particulate minerals, which include: (1) a shift in the Christiansen feature (CF) position to higher wave numbers (shorter wavelengths), (2) an increase in the overall spectral contrast, and (3) decreases in the spectral contrast of the reststrahlen bands and transparency features. Our new measurements demonstrate the high sensitivity of thermal infrared emissivity spectra to environmental conditions under which they are measured and provide important constraints for interpreting new thermal infrared data sets of the Moon, including the Diviner Lunar Radiometer Experiment onboard NASA's Lunar Reconnaissance Orbiter. Full resolution laboratory mineral spectra convolved to Diviner's three spectral channels show that spectral shape, CF position and band ratios can be used to distinguish between individual mineral groups and lunar lithologies. The integration of the thermal infrared CF position with near infrared spectral parameters allows for robust mineralogical identifications and provides a framework for future integrations of data sets across two different wavelength regimes. Copyright 2012 by the American Geophysical Union.

Investigation of new band parameters with temperature dependence for self-broadened methane gas in the range 9000 to 14,000 cm -1 (0.71 to 1.1 μm)

Journal of Quantitative Spectroscopy and Radiative Transfer (2012)

Authors:

N Bowles, R Passmore, K Smith, G Williams, S Calcutt, PGJ Irwin

Lunar regolith thermal gradients and emission spectra: Modeling and validation

Journal of Geophysical Research American Geophysical Union (AGU) 116:E12 (2011) E12003

Authors:

L Millán, I Thomas, N Bowles

A balloon-borne mission to observe Venus during the January 2014 inferior conjunction

European Space Agency, (Special Publication) ESA SP 700 SP (2011) 379-386

Authors:

E Young, M Bullock, C Tsang, J Fox, R Mellon, T Widemann, C Wilson

Abstract:

We describe a stratospheric balloon mission that will make continuous observations of Venus over a period of several weeks during the January 2014 inferior conjunction. NASA's balloon program has historically supported Antarctic flights like this one in the eliophysics and Astrophysics Divisions. The proposed experiment consists of a one meter telescope, two imaging detectors operating from 0.35 to 2.55 ! m at the diffraction limit and 33 filters. This mission will address a number of questions regarding (a) Venus' super-rotation and general circulation, (b) the properties of Venus' clouds, (c) the distribution of trace species and the coupling between certain dynamical and chemical processes, (d) the existence and prevalence of lightning on Venus, and (e) the distribution of thermal emissivity anomalies on Venus' surface. We call this mission VSS (Venus StratoScope) to keep in mind the legacy of the Stratoscope and Stratoscope II balloon missions.

Oxford SWIFT IFS and multi-wavelength observations of the Eagle galaxy at z=0.77

Monthly Notices of the Royal Astronomical Society Blackwell Publishing Inc. (2011)

Authors:

SA Kassin, L Fogarty, T Goodsall, FJ Clarke, RWC Houghton, G Salter, N Thatte, M Tecza, RL Davies, BJ Weiner, CNA Willmer, S Salim, MC Cooper, JA Newman, K Bundy, CJ Conselice, AM Koekemoer, L Lin, LA Moustakas, T Wang

Abstract:

The `Eagle' galaxy at a redshift of 0.77 is studied with the Oxford Short Wavelength Integral Field Spectrograph (SWIFT) and multi-wavelength data from the All-wavelength Extended Groth strip International Survey (AEGIS). It was chosen from AEGIS because of the bright and extended emission in its slit spectrum. Three dimensional kinematic maps of the Eagle reveal a gradient in velocity dispersion which spans 35-75 +/- 10 km/s and a rotation velocity of 25 +/- 5 km/s uncorrected for inclination. Hubble Space Telescope images suggest it is close to face-on. In comparison with galaxies from AEGIS at similar redshifts, the Eagle is extremely bright and blue in the rest-frame optical, highly star-forming, dominated by unobscured star-formation, and has a low metallicity for its size. This is consistent with its selection. The Eagle is likely undergoing a major merger and is caught in the early stage of a star-burst when it has not yet experienced metal enrichment or formed the mass of dust typically found in star-forming galaxies.