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Increment 53 - 54 Science Symposium presentation of Advanced Colloids Experiment (ACE-T6) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
Increment 53 - 54 Science Symposium presentation of Advanced Colloids Experiment (ACE-H-2) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
This paper describes a novel dual-frequency shared aperture Ka/W-band antenna design that enables wide-swath Imaging via electronic scanning at Ka-band and Is specifically applicable to NASA's Aerosol, Cloud and Ecosystems (ACE) mission. The innovative antenna design minimizes size and weight via use of a shared aperture and builds upon NASA's investments in large-aperture reflectors and high technology-readiness-level (TRL) W-band radar architectures. The antenna is comprised of a primary cylindrical reflector/reflectarray surface illuminated by a fixed W-band feed and a Ka-band Active Electronically Scanned Array (AESA) line feed. The reflectarray surface provides beam focusing at W-band, but is transparent at Ka-band.
In this talk we present an overview of Observing System Simulation Experiments (OSSEs) of relevance to the Aerosol-Cloud-Ecosystems (ACE) pre-formulation study and to the Aerosols and Cloud, Convection & Precipitation (A-CCP) Designated Observables recommended by the 2017 Decadal Survey. We start by defining the scope of OSSEs that are applicable to climate and atmospheric composition missions, followed by a theoretical discussion of retrieval error chacterizations. We conclude some examples of retrieval OSSEs and a summary of other OSSE activities of relevance.
Increment 57 - 58 Science Symposium presentation of Advanced Colloids Experiment (ACE-T2) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
The UAS in the NAS project is studying the minimum operational performance standards for unmanned aerial systems (UAS's) detect-and-avoid (DAA) system in order to operate in the National Airspace System. The DoD's Science and research Panel Well-Clear Workshop is investigating the time and spatial boundary at which an UAS violates well-clear. NASA is supporting this effort through use of its Airspace Concept Evaluation System (ACES) simulation platform. This presentation reviews how the simulation was used to support this work, lessons learned during the experiment, and introduces preliminary results.
Increment 59-60 Science Symposium presentation of Advanced Colloids Experiment (ACE-T11, Khusid - NJIT (New Jersey Inst. of Technology)) to RPO (Research Program Office). The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators. It is often assumed that time-average weightlessness simulated in a clinostat can reduce the effect of gravity on samples. Why not use it for colloids? Low-gravity parabolic flight tests on a non-buoyancy matched suspension demonstrated that time-average weightlessness in a clinostat does not eliminate gravity effect on patterns in colloids formed by an electric field. The long-term microgravity ISS (International Space Station) experiment provides a unique opportunity to reveal the relationship between external forces on the scale of individual particles and the colloid dynamics on the macroscopic scale.
Increment 57-58 Science Symposium presentation of Advanced Colloids Experiment (ACE-T12) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators. This flight experiment was added after the Science Symposium, so these charts for more for reference, than presentation.
Increment 59-60 Science Symposium presentation of Advanced Colloids Experiment (ACE-T10) (by GRC (Glenn Research Center) to the RPO-JSC (Research Planning Office-Johnson Space Center), via WebEx. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 (SC-228) is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements as well as the safety substantiation and end-to-end assessment of DAA system performance. With regard to the safety aspect being studied by the SC-228 DAA Safety sub-group, NASA has conducted a study using the ACES (Airspace Concept Evaluation System) simulation capability to determine: 1) the rate at which IFR aircraft encounter other IFR and VFR aircraft, and 2) the rate at which UAS aircraft encounter VFR aircraft as well as the corresponding encounter geometries. Five different separation thresholds were used (two for encounter and one each for well-clear, near mid-air collision, and closest point of approach). The results will be used by the SC-228 DAA Safety sub-group to inform decisions about the safety aspect of UAS DAA systems and future requirements development and validation efforts.
Increment 59-60 Science Symposium presentation of Advanced Colloids Experiment (ACE-T10) (by GRC (Glenn Research Center) to the RPO-JSC (Research Planning Office-Johnson Space Center), via WebEx. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
The attached will be presented at the JSC Science Symposium as a preview of the ACE-T5 flight experiment. The Principal Investigator (PI) for this experiment is Professor Ali Mohraz at the University of California - Irvine.Bijels (bicontinuous interfacially jammed emulsion gels) were discovered in 2007 at the University of Edinburgh. These materials feature a tubular, bicontinuous arrangement of two fluid phases separated by a monolayer of jammed colloidal particles at the interface.Because of their unique morphological characteristics, bijels hold significant promise as next-generation materials for energy and biotechnology applications. But in order to fully realize their potential, their physics and mechanical properties must be better understood. The mechanical properties and stability of bijels is mediated by an interplay between interfacial forces that impart elasticity to the system, and external stresses. Unfortunately, the interfacial forces are inherently coupled with density differences and cannot be studied systematically in the presence of gravity.
Two-dimensional position-sensitive silicon detectors (matrix detectors) have been designed, procured, and tested as part of the development of the Solar Isotope Spectrometer (SIS) instrument for NASA's Advanced Composition Explorer (ACE) mission. Important characteristics of these devices include: thickness approx. 50-90µm, active area 34 cm 2 , 64 strips on each surface with 1 mm strip pitch.
We report on extensive tests of large-area (10cm diameter) high-purity ion-implanted silicon detectors for th Solar Isotope Spectrometer (SIS), and lithium-drifted silicon detetors for the Cosmic Ray Isotope Spectrometer (CRIS), which are under development for launch on the Advanced Composition Explorer (ACE) mission.
In this paper we illustrate the unique dataset collected during the Global Precipitation Measurement Cold-season Precipitation Experiment (GCPEx, US/Canada Jan/Feb 2012). We will focus on the significance of these observations for the development of algorithms for GPM and ACE, with particular attention to classification and retrievals of frozen and mixed phase hydrometeors.
ISS Increment 65 Science Symposium Advanced Colloids Experiment (Temperature controlled) – ACE-T11(R)
With their extensive coverage, low clouds greatly impact global climate. Presently, low clouds are poorly represented in global climate models (GCMs), and the response of low clouds to changes in atmospheric greenhouse gases and aerosols remains the major source of uncertainty in climate simulations. The poor representations of low clouds in GCMs are in part due to inadequate observations of their microphysical and macrophysical structures, radiative effects, and the associated aerosol distribution and budget in regions where the aerosol impact is the greatest. The Eastern North Atlantic (ENA) is a region of persistent but diverse subtropical marine boundary layer (MBL) clouds, whose albedo and precipitation are highly susceptible to perturbations in aerosol properties. Boundary-layer aerosol in the ENA region is influenced by a variety of sources, leading to strong variations in cloud condensation nuclei (CCN) concentration and aerosol optical properties. A permanent ENA site was established by the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) user facility on Graciosa Island in the Azores, providing invaluable information on MBL aerosol and low clouds. At the same time, the vertical structures and horizontal variabilities of aerosol, trace gases, cloud, drizzle, and atmospheric thermodynamics are critically needed for understanding and quantifying the budget of MBL aerosol, the radiative properties, precipitation efficiency, and lifecycle of MBL clouds, and the cloud response to aerosol perturbations. Much of this data can be obtained only through aircraft-based measurements. In addition, the interconnected aerosol and cloud processes are best investigated by a study involving simultaneous in situ aerosol, cloud, and thermodynamics measurements. Furthermore, in situ measurements are also necessary for validating and improving ground-based retrieval algorithms at the ENA site. The Aerosol and Cloud Experiments in Eastern North Atlantic (ACE-ENA) project was motivated by the need for comprehensive in situ characterizations of boundary-layer structure, and associated vertical distributions and horizontal variabilities of low clouds and aerosol over the Azores. The ARM Aerial Facility (AAF) Gulfstream-1 (G-1) aircraft was deployed during two intensive measurement periods (IOPs). The first deployment took place from June 21 to July 20, 2017, and the second one took place from January 15 to February 18, 2018. Flights were carried out in the Azores, near the ARM ENA site on Graciosa Island. Deployments during both seasons allow for examination of key aerosol and cloud processes under a variety of representative meteorological and cloud conditions. The science themes for the deployments include: (1) Budget of MBL CCN and its seasonal variation; (2) Effects of aerosol on cloud and precipitation; (3) Cloud microphysical and macrophysical structures, and entrainment mixing; (4) Advancing retrievals of turbulence, cloud, and drizzle; and (5) Model evaluation and processes studies.
In February 2018, the National Nuclear Data Center released ENDF/B-VIII.0 in the standard Evaluated Nuclear Data Format (ENDF). This represents the advances made in nuclear data since the release of ENDF/B-VII.1 in 2011.