82 research outputs found
THE VERITAS 2023 ICELAND ANALOG CAMPAIGN - DIELECTRIC PERMITTIVITY AND SAMPLING
No full textThe Veritas Team: Jeffrey Andrews-Hanna, Doris Breuer, Debra Buczkowski, Bruce Campbell, Anne Davaille, Gaetano Di Achille, M. Darby Dyar, Caleb Fassett, Martha Gilmore, Scott Hensley, Robert Herrick, Luciano Iess, Lauren Jozwiak, Marco Mastrogiuseppe, Erwan Mazarico, Nils Mueller, Daniel Nunes, Sue Smrekar, Joann Stock, Thomas Widemann, Jennifer Whitten, Howard Zebker, Solmaz Adeli, Giulia Alemanno, Jacopo Baccarin, Laura Breitenfeld, Gael Cascioli, Ankita Das, Fabrizio deMarchi, Daniele Durante, Michael Eineder, Indujaa Ganesh, Stephen Garland, Flavia Giuliani, Anna Gcher, Christopher Hamilton, Jim Head, Jrn Helbert, Oddisey Knox, Julia Maia, Alessandro Maturilli, Gro B. M. Pedersen, Erin Pimentel, Ana-Catalina Ina Plesa", Pau Prats, Maria Carmela Raguso, Joseph Schools, Ellen Stofan, Michaela Walterov, Cai Ytsma,5th Lunar and Planetary Science Conference (LPSC), Woodlands, Texas and virtually, March 11, 2024The VERITAS Science Team conducted a Venus field-analog campaign to support interpretation of X-band and NIR data, test data processing algorithms, and comparison with S-band SAR from other missions (Magellan, EnVision).unding for the Iceland campaign comes from NASA to JPL/VERITAS, NASA to Goddard/GIFT, and DLR. Laboratory support comes Barmatz.https://www.hou.usra.edu/meetings/lpsc2024/pdf/1706.pd
VERITAS (Venus Emissivity, Radio science, InSAR, Topography, And Spectroscopy): Discovering the Secrets of a Lost Habitable World
Get PDFVERITAS is a selected Discovery mission launching in 2028. It will investigate Venus’ geologic evolution and processes that affect rock planetary habitability. Venus’ present condition is a geodynamic analog for early Earth, when the lithosphere was hotter and thinner, plate tectonics and continents began to form, and life emerged. Earth no longer retains a clear record of how these processes began, but Venus may have active subduction—the necessary first step to initiate plate tectonics, as well as analogs of continents. VERITAS will test whether Venus’ tessera plateaus represent the only analogs of continents in the solar system, which formed on Earth when massive quantities of basalt melted in the presence of water. VERITAS will use numerous methods to search for current volcanism and tectonism, including subduction.
VERITAS produces global, foundational datasets using two instruments, the Venus Interferometric Synthetic Aperture Radar (VISAR) and the Venus Emissivity Mapper (VEM), plus a gravity science investigation. The VISAR X-band measurements include: 1) a global digital elevation model (DEM) with 250 m postings, 6 m height accuracy, 2) Synthetic aperture radar (SAR) imaging at 30 m horizontal resolution globally, 3) SAR imaging at 15 m for >25% of the surface, and 4) surface deformation from repeat pass interferometry (RPI) at 2 cm precision for >12 targeted areas. VEM covers >70% of the surface in six NIR bands located within five atmospheric windows sensitive to Fe mineralogy, plus eight atmospheric bands for calibration and water vapor measurements, with SNR ≫ VIRTIS. It is a near IR spectral imager with optimized spectral bands for observing the surface of Venus that supports the determination of rock type and the search for active and recent volcanism. VERITAS will use a low circular orbit (< 250 km) and Ka-band uplink and downlink to create a global gravity field with 3 mGal accuracy at 155 km (d&o 123) resolution. VERTIAS also constrains core size and state, using radar tie points to help find k2, the phase lag, and MOIF
TOPOGRAPHIC DATA ACQUISITION FOR THE VERITAS 2023 ICELAND FIELD CAMPAIGN
No full text5th Lunar and Planetary Science Conference (LPSC), Woodlands, Texas and virtually, March 11, 2024The NASA Discovery mission VERITAS (Venus Emissivity, Radio Science, InSAR,Topography, and Spectroscopy) will explore Venus in the early 2030s, acquiring foundational global datasets that will reshape our understanding of planetary evolution [1]. In addition to a gravity science investigation [2] and a near-infrared spectrometer(VEM) [3], a synthetic aperture radar (VISAR) [4] will globally map the surface at X-band wavelength (~4 cm). To better interpret the radar backscatter measurements,relate them to physical properties such as surface roughness, and intercompare them with other radar datasets (Magellan S-band and EnVision VenSAR Sband), the VERITAS science team conducted a field campaign in Iceland, in collaboration with a multi-bandradar mapping airborne campaign by the German Aerospace Center (DLR) [5,6]https://www.hou.usra.edu/meetings/lpsc2024/pdf/1142.pd
Topographic Data Acquisition for the VERITAS 2023 Iceland Field Campaign
Get PDFThe NASA Discovery mission VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) will explore Venus in the early 2030s, acquiring foundational global datasets that will reshape our understanding of planetary evolution [1]. In addition to a gravity science investigation [2] and a near-infrared spectrometer (VEM) [3], a synthetic aperture radar (VISAR) [4] will globally map the surface at X-band wavelength (~4 cm). To better interpret the radar backscatter measurements, relate them to physical properties such as surface roughness, and intercompare them with other radar datasets (Magellan S-band and EnVision VenSAR S-band), the VERITAS science team conducted a field campaign in Iceland, in collaboration with a multi-band radar mapping airborne campaign by the German Aerospace Center (DLR) [5,6]
The VERITAS 2023 Iceland Analog Campaign - Dielectric Permittivity and Sampling
Get PDFThe Venus Emissivity, Radio Science, InSAR, Topography and Spectroscopy (VERITAS) Discovery mission will map the surface with NIR spectroscopy using the VEM instrument and SAR using X-band (4 cm) with the VISAR instrument [1]. The VERITAS Science team conducted a field analog campaign in Iceland over two weeks in August 2023 in collaboration with the German Aerospace Center (DLR), employing both an airborne radar mapping effort and an in-situ surface characterization task [2]. The latter serves as ground truth to the radar data by providing concurrent measurements of the parameters that control radar backscatter, such as topography, roughness, and dielectric permittivity. Here we report on in-situ permittivity measurements, sampling, and laboratory measurements
Near-Infrared Data Acquisition for the VERITAS 2023 Iceland Field Campaign
No full textEuroplanet Science Congress 2024, Henry Ford Building, Freie Universität Berlin, German,8–13 September 2024In this campaign, we collected in-situ NIR data and 60 kg of samples of Venus analog materials. We are currently at the post-processing phase of the data and sample analyses. Correlation with the surface roughness and permittivity is also planned for the near future. By comparing the field and laboratory datasets, we can assess the capabilities of the VEM instrument in distinguishing lava types and compositions. Correlation with other field datasets will help finding close synergies with other instruments in preparation for the Venus missions. This work lays a foundation for detailed interpretation of Venus mineralogy and is vital preparation for the scientific goals of the NASA VERITAS and ESA EnVision.SA, SPG, NM, AD received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 871149. GC, EM was supported by NASA Planetary Science Division Research Program through the GSFC GIFT ISFM.https://meetingorganizer.copernicus.org/EPSC2024/EPSC2024-918.htm
A quantitative assessment of the prion risk associated with wastewater from carcase-handling facilities
No full textWastewater from facilities processing livestock that may harbor transmissible spongiform encephalopathies (TSEs) infectivity is permitted under license for application to land where susceptible livestock may have access. Several previous risk assessments have investigated the risk of bovine spongiform encephalopathy (BSE) associated with wastewater effluents; however, the risk of exposure to classical scrapie and atypical scrapie has not been assessed. With the prevalence of certain TSEs (BSE in cattle and classical scrapie in sheep) steadily in decline, and with considerable changes in the structure of carcase-processing industries in Great Britain, a reappraisal of the TSE risk posed by wastewater is required. Our results indicate that the predicted number of new TSE infections arising from the spreading of wastewater on pasture over one year would be low, with a mean of one infection every 1,000 years for BSE in cattle (769, 555,556), and one infection every 30 years (16, 2,500), and 33 years (16, 3,333) for classical and atypical scrapie, respectively. It is assumed that the values and assumptions used in this risk assessment remain constant. For BSE in cattle the main contributors are abattoir and rendering effluent, contributing 35% and 22% of the total number of new BSE infections. For TSEs in sheep, effluent from small incinerators and rendering plants are the major contributors (on average 32% and 31% of the total number of new classical scrapie and atypical scrapie infections). This is a reflection of the volume of carcase material and Category 1 material flow through such facilities
First NuSTAR Observations of Mrk 501 within a Radio to TeV Multi-Instrument Campaign
No full textVK: BIBCODE: 2015ApJ...812...65F; DOI: 10.1088/0004-637X/812/1/65; eprintid: arXiv:1509.04936We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During the campaign, the nearby BL Lac object was observed in both a quiescent and an elevated state. The broadband campaign includes observations with NuSTAR, MAGIC, VERITAS, the Fermi Large Area Telescope, Swift X-ray Telescope and UV Optical Telescope, various ground-based optical instruments, including the GASP-WEBT program, aswell as radio observations by OVRO, Metsähovi, and the F-Gamma consortium. Some of the MAGIC observations were affected by a sand layer from the Saharan desert, and had to be corrected using event-by-event corrections derived with a Light Detection and Ranging (LIDAR) facility.This is the first time that LIDAR information is used to produce a physics result with Cherenkov Telescope data taken during adverse atmospheric conditions, and hence sets a precedent for the current andfuture ground-based gamma-ray instruments. The NuSTAR instrument provides unprecedented sensitivity in hard X-rays, showing the source to display a spectral energy distribution (SED) between 3 and 79 keV consistent with a log-parabolic spectrum and hard X-ray variability onhour timescales. None (of the four extended NuSTAR observations) show evidence of the onset of inverse-Compton emission at hard X-ray energies. We apply a single-zone equilibrium synchrotron self-Compton(SSC) model to five simultaneous broadband SEDs. We find that the SSC model can reproduce the observed broadband states through a decrease inthe magnetic field strength coinciding with an increase in the luminosity and hardness of the relativistic leptons responsible for the high-energy emission.Peer reviewe
The VERITAS 2023 Iceland Analog Campaign
Get PDFDespite near-global scale coverage with Magellan synthetic aperture radar (SAR) imaging of Venus, first-order questions remain about our closest planetary neighbor. This is in part due to (i) remote sensing of the surface restriction to very few wavelengths in the electromagnetic spectrum, and (ii) the low resolution of our best image, topographic, and geophysical data sets. The Venus Emissivity, Radio Science, InSAR, Topography and Spectroscopy (VERITAS) Discovery mission will map the surface with SAR using X-band (4 cm) using the VISAR instrument, and with 6 finely tuned Near-IR bands using the VEM instrument [1]. As a result, it will achieve unprecedented resolution in imagery and topography, as well as detect surface rock types and change over time. To support interpretation of X-band and NIR data, test data processing algorithms, and comparison with S- band SAR from other missions (Magellan, EnVision), the VERITAS Science Team conducted a field analog campaign over two weeks in August 2023 in collaboration with the German Aerospace Center (DLR), which involved both an airborne radar mapping effort and an in-situ surface characterization task. The latter provides ground truth for parameters that affect radar backscatter (topography, roughness, dielectric permittivity) and NIR emissivity
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