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The SEEDs of Planet Formation: Indirect Signatures of Giant Planets in Transitional Disks
We live in a planetary system with 2 gas giant planets, and as a resu lt of RV, transit, microlensing, and transit timing studies have ide ntified hundreds of giant planet candidates in the past 15 years. Su ch studies have preferentially concentrated on older, low activity So lar analogs, and thus tell us little about .when, where, and how gian t planets form in their disks, or how frequently they form in disks associated with intermediate-mass stars.
Hydrocarbon-Seeded Ignition System for Small Spacecraft Thrusters Using Ionic Liquid Propellants
"Green" propellants based on Ionic-liquids (ILs) like Ammonium DiNitramide and Hydroxyl Ammonium Nitrate have recently been developed as reduced-hazard replacements for hydrazine. Compared to hydrazine, ILs offer up to a 50% improvement in available density-specific impulse. These materials present minimal vapor hazard at room temperature, and this property makes IL's potentially advantageous for "ride-share" launch opportunities where hazards introduced by hydrazine servicing are cost-prohibitive. Even though ILs present a reduced hazard compared to hydrazine, in crystalline form they are potentially explosive and are mixed in aqueous solutions to buffer against explosion. Unfortunately, the high water content makes IL-propellants difficult to ignite and currently a reliable "coldstart" capability does not exist. For reliable ignition, IL-propellants catalyst beds must be pre-heated to greater than 350 C before firing. The required preheat power source is substantial and presents a significant disadvantage for SmallSats where power budgets are extremely limited. Design and development of a "micro-hybrid" igniter designed to act as a "drop-in" replacement for existing IL catalyst beds is presented. The design requires significantly lower input energy and offers a smaller overall form factor. Unlike single-use "squib" pyrotechnic igniters, the system allows the gas generation cycle to be terminated and reinitiated on demand.
Transitional Disks Associated With Intermediate-mass Stars: Results of the SEEDS YSO survey
As part of the Strategic Exploration of Exoplanets and Disks with Subaru YSO survey, we have surveyed a number of Herbig B-F stars at H-band using Polarimetric Differential Imaging+Angular differential imaging. Historically, Herbig stars have been sorted based on their IR SEDs into those with SEDS which can be fit by powerlaws over 1-200 μm (Meeus et al. 2001, group II), and those which can be interpreted as a powerlaw + a blackbody component (Meeus group I) or powerlaw+missing warm thermal emission, which is one of the criteria for identification of gapped or transitional disks. Meeus group II disks, when imaged with HiCIAO show featureless disks with depolarization along the projection of the disk semi-minor axis (Kusakabe et al. 2012). This is what we had expected to see for the Meeus group I disks, except for the addition of wide gaps or central cavities. Instead we find wild diversity, suggesting that transitional disks are highly perturbed compared to Meeus group II disks.
Imaging Transitional Disks with TMT: Lessons Learned from the SEEDS Survey
TMT studies of the early phases of giant planet formation will build on studies carried out in this decade using 8-meter class telescopes. One such study is the Strategic Exploration of Exoplanets and Disks with Subaru transitional disk survey. We have found a wealth of indirect signatures of giant planet presence, including spiral arms, pericenter offsets of the outer disk from the star, and changes in disk color at the inner edge of the outer disk in intermediate-mass PMS star disks. T Tauri star transitional disks are less flamboyant, but are also dynamically colder: any spiral arms in these diskswill be more tightly wound. Imaging such features at the distance of the nearest star-forming regions requires higher angular resolution than achieved with HiCIAO+ AO188. Imaging such disks with extreme AO systems requires use of laser guide stars, and are infeasible with the extreme AO systems currently commissioning on 8-meter class telescopes. Similarly, the JWST and AFTAWFIRST coronagraphs being considered have inner working angles 0.2, and will occult the inner 28 atomic units of systems at d140pc, a region where both high-contrast imagery and ALMA data indicate that giant planets are located in transitional disks. However, studies of transitional disks associated with solar-mass stars and their planet complement are feasible with TMT using NFIRAOS.
Post-Flight Test Results of Seed Laser Module Subjected to Space Exposure
The objective of the Materials International Space Station Experiment (MISSE) is to study the performance of novel materials when subjected to the synergistic effects of the harsh space environment for several months. MISSE missions provide an opportunity for developing space qualifiable materials. Several laser and lidar components were sent by NASA Langley Research Center (LaRC) as a part of the MISSE 7 mission. The MISSE 7 module was transported to the international space station (ISS) via STS 129 mission that was launched on Nov 16, 2009. Later, the MISSE 7 module was brought back to the earth via the STS 134 that landed on June 1, 2011. The MISSE 7 module that was subjected to exposure in space environment for more than one and a half year included fiber laser, solid-state laser gain materials, detectors, and semiconductor laser diode. Performance testing of these components is now progressing. In this paper, the results of performance testing of a laser diode module sent by NASA Langley Research Center on MISSE 7 mission will be discussed. This paper will present the comparison of pre-flight and post-flight performance curves and discuss the effect of space exposure on the laser diode module. Preliminary findings on output power measurements show that the COTS laser diode characteristics did not undergo any significant performance degradation.
SEEDS Direct Imaging of the RV-Detected Companion to V450 Andromedae, and Characterization of the System
We report the direct imaging detection of a low-mass companion to a young, moderately active star V450 And, that was previously identified with the radial velocity (RV) method. The companion was found in high-contrast images obtained with the Subaru Telescope equipped with the HiCIAO camera and AO188 adaptive optics system. From the public ELODIE and SOPHIE archives we extracted available high-resolution spectra and RV measurements, along with RVs from the Lick planet search program. We combined our multi-epoch astrometry with these archival, partially unpublished RVs, and found that the companion is a low-mass star, not a brown dwarf, as previously suggested. We found the best-fitting dynamical masses to be m(sub 1) = 1.141(sup + 0.037, sub - 0.091) and m(sub 2) = 0.279(sup + 0.023, sub - 0.020) solar mass. We also performed spectral analysis of the SOPHIE spectra with the iSpec code. Hipparcos time-series photometry shows a periodicity of P = 5.743 day, which is also seen in the SOPHIE spectra as an RV modulation of the star A. We interpret it as being caused by spots on the stellar surface, and the star to be rotating with the given period. From the rotation and level of activity, we found that the system is 380(sup + 220, sub -100) Myr old, consistent with an isochrone analysis (220 (sup +2120, sub -90) Myr). This work may serve as a test case for future studies of low mass stars, brown dwarfs, and exoplanets by combination of RV and direct imaging data.
Insights into Space Solar Cell Durability Using SPICE Simulation Seeded by Current-Voltage Characteristics Parametrized Using the Lambert W Special Function
We developed and validated an automated routine for the fitting of I-V curve data to the single diode model according to an exact analytical solution. Our fitting routine was validated to show good noise immunity and high accuracy usingsimulated values from LTSPICE. We are thus able to automate parameter extraction from a dataset or arbitrary size. This parameterization allows for better simulation of performance of real cells and arrays and provides utility for a host of applications relevant to space arrays. We will use this methodology to determine the array performance of radiated cells over time, and simulate the performance of the arrays with bypass diodes and power electronics.
Small Businesses Tap into America’s Seed Fund and Help NASA
U.S. companies with less than 500 employees can receive funding to pursue innovative ideas while helping address our nation’s technical challenges, thanks to the Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs. Here are just a few of the hundreds of companies—spanning a wide range of industries—that used SBIR/STTR funds from NASA for their cutting-edge research and development (R&D). Through SBIR/STTR, small companies successfully access new markets, grow their business, and expand their capabilities while helping NASA achieve its goals.
Use of Synectics as an Idea Seeding Technique to Enhance Design Creativity
An approach to generated creative design that employs the practice of synectics is presented.
X-Ray Binary Luminosity Function Scaling Relations in Elliptical Galaxies: Evidence for Globular Cluster Seeding of Low-Mass X-Ray Binaries in Galactic Fields
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Carolina Coastal Plain: Ecological Forecasting - Utilizing NASA Earth Observations to Map Suitable Venus Flytrap Habitat to Inform Conservation Efforts, Seed Banking, and Reintroduction in the Carolina Coastal Plain and Sandhills Region
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Seeding Method for Velocimetry and Visualization of Supersonic Retropropulsion Nozzle Plumes
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Did an Ancient Habitable Venus Provide the Seeds for Life Today?
Recent possible detections of Phosphine in the Venusian atmosphere [1,2] have spurred interest in the potential for life in the clouds of Venus given the limited number of abiotic alternatives determined thus far [3]. A number of theories have been posited as to how life could have arisen in the cloud decks of Venus (e.g. [4] and references therein) and how it might thrive in a supposedly hostile environment [5]. Over the past few years we have used forward modeling to investigate the possibilities of a temperate Venusian climate in its deep past. This affords us the opportunity to discuss the possibility for an early habitable Venus and its implications for habitability in the cloud layers today.
Impact of Space Radiation on Plant Seeds: From Arabidopsis Thaliana to Crops
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Seeding Innovative Ideas and Partnering with the Ecosystem
Jenn Gustetic will talk about how NASA selects ideas and collaborates with the ecosystem to develop new technologies for NASA’s portfolio. She will explain how the organization encourages collaboration, co-invests to develop ideas from lab to market, and acts as the hub-and-spoke of the ecosystem. Jenn will also discuss NASA’s journey to break silos and work horizontally across programs. • Gathering and evaluating ideas internally and externally with diverse players – engaging communities, being the hub-and-spoke of the ecosystem, and encouraging collaboration through co-investments • Identify the best ideas, funding ideas from maturation to hand-off with fluctuating budgets, and managing IP and tech transfer • Balancing investments in projects that address NASA’s needs with higher risk ideas that may not have an obvious application • Transitioning ideas to the next phase – training people and teams and ensuring ownership • Developing a 3.0 innovation capacity strategy – disrupting silos, enabling the ecosystem to work seamlessly together, and taking people and leaders along
Plasma Produced Gaseous Species for Food, Seed, and Equipment Sanitization
Researchers at KSC have shown that plasma produced gaseous species have shown greater than 5.89 log reduction of inoculated coupons and sanitization (greater than 3 log reduction) of produce and 3D printed materials, though with more variable results. The results were obtained using a recirculating plasma system, with 1 L of air, 1 mL of H 2 O, and less than 500 W of power being the only consumable commodities. The work is versatile and enabling for future missions since the air and the produced gases can be reused or recycled on board the spacecraft.
Accelerated Growth of Seed Black Holes by Dust in the Early Universe
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