[1] The NASA Discovery Moon Mineralogy Mapper imaging spectrometer was selected to pursue a wide range of science objectives requiring measurement of composition at fine spatial scales over the full lunar surface. To pursue these objectives, a broad spectral range imaging spectrometer with high uniformity and high signal-to-noise ratio capable of measuring compositionally diagnostic spectral absorption features from a wide variety of known and possible lunar materials was required. For this purpose the Moon Mineralogy Mapper imaging spectrometer was designed and developed that measures the spectral range from 430 to 3000 nm with 10 nm spectral sampling through a 24 degree field of view with 0.7 milliradian spatial sampling. The instrument has a signal-to-noise ratio of greater than 400 for the specified equatorial reference radiance and greater than 100 for the polar reference radiance. The spectral cross-track uniformity is >90% and spectral instantaneous field-of-view uniformity is >90%. The Moon Mineralogy Mapper was launched on Chandrayaan-1 on the 22nd of October. On the 18th of November 2008 the Moon Mineralogy Mapper was turned on and collected a first light data set within 24 h. During this early checkout period and throughout the mission the spacecraft thermal environment and orbital parameters varied more than expected and placed operational and data quality constraints on the measurements. On the 29th of August 2009, spacecraft communication was lost. Over the course of the flight mission 1542 downlinked data sets were acquired that provide coverage of more than 95% of the lunar surface. An end-to-end science data calibration system was developed and all measurements have been passed through this system and delivered to the Planetary Data System (PDS.NASA.GOV). An extensive effort has been undertaken by the science team to validate the Moon Mineralogy Mapper science measurements in the context of the mission objectives. A focused spectral, radiometric, spatial, and uniformity validation effort has been pursued
ASTERIA (Arcsecond Space Telescope Enabling Research In Astrophysics) is a 6U CubeSat space telescope (10 cm x 20 cm x 30 cm, 10 kg). ASTERIA's primary mission objective was demonstrating two key technologies for reducing systematic noise in photometric observations: high-precision pointing control and high-stabilty thermal control. ASTERIA demonstrated 0.5 arcsecond RMS pointing stability and ±10 milliKelvin thermal control of its camera payload during its primary mission, a significant improvement in pointing and thermal performance compared to other spacecraft in ASTERIA's size and mass class. ASTERIA launched in August 2017 and deployed from the International Space Station (ISS) November 2017. During the prime mission (November 2017 -February 2018) and the first extended mission that followed (March 2018 -May 2018), ASTERIA conducted opportunistic science observations which included collection of photometric data on 55 Cancri, a nearby exoplanetary system with a super-Earth transiting planet. The 55 Cancri data were reduced using a custom pipeline to correct CMOS detector column-dependent gain variations. A Markov Chain Monte Carlo (MCMC) approach was used to simultaneously detrend the photometry using a simple baseline model and fit a transit model. ASTERIA made a marginal detection of the known transiting exoplanet 55 Cancri e (∼ 2 R ⊕ ), measuring a transit depth of 374 ± 170 ppm. This is the first detection of an exo-
Recently, algae have received significant interest as a potential feedstock for renewable diesel (such as biodiesel), and many researchers have attempted to quantify this potential. Some of these attempts are less useful because they have not incorporated specific values of algal lipid content, have not included processing inefficiencies, or omitted processing steps required for renewable diesel production. Furthermore, the associated energy, materials, and costs requirements are sometimes omitted. The accuracy and applicability of these estimates can be improved by using data that are more specific, including all relevant information for renewable diesel production, and by presenting information with more relevant metrics. To determine whether algae are a viable source for renewable diesel, three questions that must be answered are (1) how much renewable diesel can be produced from algae, (2) what is the financial cost of production, and (3) what is the energy ratio of production? To help accurately answer these questions, we propose an analytical framework and associated nomenclature system for characterizing renewable diesel production from algae. The three production pathways discussed in this study are the transesterification of extracted algal lipids, thermochemical conversion of algal biomass, and conversion of secreted algal oils. The nomenclature system is initially presented from a top-level perspective that is applicable to all production pathways for renewable diesel from algae. Then, the nomenclature is expanded to characterize the production of renewable diesel (specifically, biodiesel) from extracted algal lipids in detail (cf. Appendix 2). The analytical framework uses the presented nomenclature system and includes three main principles: using appropriate reporting metrics, using symbolic notation to represent unknown values, and presenting results that are specific to algal species, growth conditions, and product composition.
The design and demonstration of a tunable diode laser sensor for in situ temperature and water (H2O) measurements in laboratory flames is presented. A newly-designed probe consisting of two single-crystal sapphire rods is used to guide 2.9 μm laser light across the core of a flame while avoiding absorption by water outside of the flame. The sensor probes two H2O transitions near 2.9 μm using a scanned-wavelength-modulation absorption-spectroscopy spectral-fitting technique, which enables measurements without calibration or knowledge of the mixture collisional-broadening coefficient. To demonstrate the sensor, temperature and water mole fraction measurements were acquired in stoichiometric, burner-stabilized flames of methane/oxygen/argon at pressures of 25 Torr and 60 Torr. Typical total uncertainties in the temperature and water mole fraction measurements were ±50 K and ±0.016, respectively. This sensor is simple, robust and accurate and enables improved chemical kinetics studies of low-pressure flames. Improvements to reduce temperature and H2O precision to ±20 K and ±0.008, respectively, are discussed.
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