S. A. McLaughlin's research while affiliated with University of Maryland, College Park and other places

... The M 3 level 2 product contains small deviations that are corrected with scalar 'ground truth' correction factors to align them with known smooth spectral properties of lunar soils. We used the correction factors distributed by Isaacson 46 to minimize systematic errors. In addition, the spectra exceeding 2,500 nm were eliminated, considering the thermal emission effect. ...

... During the Earth-Moon system flybys, hydration on the lunar surface was investigated (Sunshine et al. 2009) and the Earth-Moon system was observed from afar as an analog extrasolar planet Crow et al. 2011). In addition, Deep Impact had a short six-month commissioning, calibration, and cruise phase from launch to approach of 9P during the primary mission, leaving much to improve upon for the extended mission, including extensive calibration campaigns throughout cruise and designing more effective observing sequences to be executed for the 103P encounter (Klaasen et al. 2013a). ...

... numerous Earth-based time-series observations of structures in the comet's coma (Meech et al., 2011; Knight and Schleicher, 2010, 2011; Samarasinha et al., 2010, 2011; Jehin et al., 2010), radar observations of the nucleus (Harmon et al., 2010, 2011), and high-spectral resolution microwave line observations of HCN (Drahus et al., 2011) indicated that the magnitude of the periodicity was increasing with time and that the spin of 103P's nucleus was probably in an excited state. That this was definitely the case was independently determined in the preliminary approach photometry and imaging results of the DIXI mission (A'Hearn et al., 2011; Belton et al., 2011a). While all of these studies were in broad agreement as to the magnitude and changes in the dominant periodicity and that a second periodicity was present, discussions at a special workshop on the subject held at the Kitt Peak National Observatory on April 5–6, 2011, showed less unanimity on the space direction of M (the rotational angular momentum per unit mass vector), the magnitude of the roll or oscillation periodicity, or whether the excited motion was in the short (SAM) or long (LAM) axis mode (see the Appendix in Samarasinha and A'Hearn (1991) for a detailed explanation of torque-free excited spin and the SAM and LAM modes). ...

... This study considers the 3-D shape and dynamic model of the nucleus. The shape model information is from the research of Thomas et al. (2013) and the rotation model is from Belton et al. (2013). The DEM (Digital Elevation Model) data used for the shape model construction is from Farnham and Thomas (2013). ...

... Ground-truth calibration and geometry corrections to the data were applied and mosaiced by using the ENVI software. The M3 data were obtained in five optical periods (OP1A, OP1B, OP2A, OP2B, and OP2C), during which coverage, altitude, phase angle, and spatial resolution varied (Besse et al., 2013). In this work, the spectral data (UV-VIS-NIR) were selected from a single optical period (OP2C), which provides low phase angles (average 25 ) coverage of most of the lunar surface Besse et al., 2013). ...

... Three narrowband filters are designed to measure different gas species (OH at 309.48 nm and CN at 388.80 nm with bandwidths 6.2 nm, and C 2 at 515.31 nm with bandwidth 11.8 nm), and two other narrowband filters are designed to measure the continuum colors at 345 nm (Violet) and 526 nm (Green); two mediumband filters are designed to measure colors at 750 nm (Red) and 950 nm (IR). The instrument is also equipped with two nearly identical broadband filters (Clear1 and Clear6) sensitive to the whole 200 -1100 nm wavelength range (Klaasen et al. 2008). The bandpass of the Clear filters includes continuum from light reflected by dust in the coma, as well as emission features from several fragment species, such as OH, CN, and C 2 . ...

... For this reason, we elected to use only the original 22 days of observations in the search for additional transits. We used the existing Deep Impact data reduction pipeline to perform bias and dark subtractions , as well as preliminary flat fielding (Klaasen et al. 2005). We first determined the position of the star on the CCD using PSF fitting, by maximizing the goodness-of-fit (with the χ 2 statistic as an estimator) between an image and a model PSF (oversampled by a factor of 100) with variable position, additive sky background, and multiplicative brightness scale factor. ...

... The M 3 data were downloaded from the Planetary Data System (http://pds-imaging.jpl.nasa.gov/data/m3/ (accessed on 29 June 2017)) [29]. We analyzed the data with latitudes above 70 • within a lunation from 24 May 2009, to 21 June 2009, during which M 3 has wider coverage [29]. ...

... The interpretation and analysis of astronomical observations of dust in comets is mainly based on our knowledge of light scattering by morphologically irregular particles. The significance of dust particles having size comparable to the wavelength of incident light has been widely acknowledged (A'Hearn et al. 1995;A'Hearn et al. 2011;Kimura et al. 2006;Das et al. 2008;Kolokolova et al. 2015;Zubko et al. 2006Zubko et al. , 2020Deb Roy et al. 2017;Halder et al. 2018;Halder & Ganesh 2021). The cosmic dust particles found in space are mainly porous fractal aggregates of smaller grains formed due to coagulation and ballistic agglomeration in the circumstellar or interstellar environment. ...

... In the end, the ejecta was quite bright and optically thick and overwhelmed some of the images. The ejecta material was so bright that it biased the autonavigation and instrument pointing of the flyby spacecraft, which misinterpreted the ejecta as part of the nucleus and thus pointed further from the impact site than the planned center of brightness offset (Klaasen et al. 2008). ...