- API data.nasa.gov | Last Updated 2018-07-19T04:47:22.000Z
This data set contains CODMAC level 3 cometary, calibration, and instrument checkout data acquired by the Rosetta Orbiter ALICE UV Spectrometer during the first commissioning phase of the Rosetta mission, which occurred March 5, 2004 to June 6, 2004.
- API data.nasa.gov | Last Updated 2018-09-07T17:39:46.000Z
<p>Future astrophysics missions require efficient, low-temperature cryocoolers to cool advanced instruments or serve as the upper stage cooler for sub-Kelvin refrigerators. Potential astrophysics missions include Lynx, the Origin Space Telescope, and the Superconducting Gravity Gradiometer. Cooling loads for these missions are up to 300 mW at temperatures of 4 to 10 K, with additional loads at higher temperatures for other subsystems. Due to low jitter requirements, a cryocooler with very low vibration is needed for many missions. In addition, a multi-stage cooler, capable of providing refrigeration at more than one temperature simultaneously, can provide the greatest system efficiency with the lowest mass. Turbo-Brayton cryocoolers have space heritage and are ideal for these missions due to negligible vibration emittance and high efficiency at low temperatures. The primary limitation in implementing Brayton cryocoolers at temperatures below 10 K has been the development of high efficiency turbines. On the proposed program, Creare plans to leverage recent developments in gas bearing technology and low-temperature alternators to realize a high-efficiency, low-temperature turbine. On the Phase I project, we will perform a proof-of-concept demonstration of the turbine technology at temperatures down to 4 K. On the Phase II project, we will build and demonstrate an advanced low-temperature turbine at temperatures of 4 to 10 K.</p>
- API data.nasa.gov | Last Updated 2018-08-02T15:25:24.000Z
This grouping contains the incompressible-flow cases from the 1980-81 Data Library.
- API data.nasa.gov | Last Updated 2018-07-19T08:38:04.000Z
<p>We propose to enhance GSFC’s interplanetary mission design capability by designing a fully automated multi-spacecraft multi-objective interplanetary global trajectory optimization transcription. Advanced trajectory design technologies including the ability to design Distributed Spacecraft Missions (DSMs) are attracting increased interest but no mission design tool is currently capable of performing mission and systems design/optimization for an interplanetary DSM. This effort will deliver a software prototype capable of building the optimal design of a DSM-class mission where multiple spacecraft depart to the heliocentric regime from the same launch vehicle to perform coordinated science. This new capability will lay the groundwork for a follow-on proposal to implement this new capability into NASA Goddard's Evolutionary Mission Trajectory Generator (EMTG) where it will enable new announcements of opportunity for Distributed Spacecraft Missions.</p>
- API data.nasa.gov | Last Updated 2018-09-05T23:06:09.000Z
Missions to Enceladus that want to determine the habitability of its icy ocean and search for extant life must acquire a pristine sample of the Enceladus ocean brine. The missions can either be accomplished via a lander or flythroughs of the plumes. From the mission and flight system design perspective, flythroughs incur less risk. Also, the planetary protection requirements are easier to meet. One of the key challenges for these missions is to avoid ambiguity of results that has plagued previous astrobiological efforts (e.g. Viking). Therefore, the system must collect a large enough sample to enable analysis by several independent techniques. In addition, the sample collection process must not alter or contaminate the sample, which can skew the analysis. The reliability of the collector after a long cruise time, its cleanliness and low mass are also key concerns. The goal of this proposal is to mature a sample collection mechanism to obtain a pristine sample of the ocean water via multiple flythroughs of the Enceladus icy plumes. The requirements for the sample collector include a large collector area to acquire the most sample while ensuring that it is efficiently transferred into a very small holding volume. It must preserve the sample in its pristine ice form until the instruments are ready to perform analysis and then efficiently transfer the sample to the downstream instruments. EFun is a square meter, <2kg funnel shaped collector that was designed as part of JHU/APL internal development, achieving TRL 3. As the icy particles enter the collector area, they are guided into a small holding volume. Once the ice is in the holder, EFun transforms the sample into liquid, prepares it by controlled dilution, and employs a syringe-like piston to distribute the sample to the instruments. A smaller version of the collector front end was prototyped and tested at NASA Ames vertical gun facility in vacuum and at temperature. These test have proven the integrity of the sample and characterized its collecting efficiency. Under ColdTech, we propose to prototype and test the holding volume of the collector and the sample preparation steps of melting, dilution, and transfer to downstream instruments. The goal is the development of a highly efficient and reliable system. This prototype will then be integrated with the large area collector and be tested as a complete system at Ames over the full range of expected plume environments. We will demonstrate end-to-end sample acquisition, liquefaction, and distribution. In addition, we would design a door mechanism to keep the collector area clean during the cruise. At the end of ColdTech, EFun would achieve TRL 5 and be ready to be proposed in upcoming missions.
- API data.nasa.gov | Last Updated 2018-07-19T08:48:46.000Z
<p>Frequent, short-term crew exposure to elevated CO2 levels combined with other physiological impacts of microgravity may lead to a number of detrimental effects, including loss of vision. This technology project seeks to develop a prototype of a real-time location system integrated with a CO2 sensor to monitor and correlate space-time-CO2 concentration with physical symptoms and functional evaluations of impairment. The CO2 sensor will be integrated with a low-power ultra-wideband (UWB) communication system with location-tracking capability. Although the initial development is oriented to the measurement of CO2, the system concept can easily be adapted to accommodate other types of sensors. <p/><p>Recent findings indicate that frequent, short-term crew exposure to elevated CO2 levels combined with other physiological impacts of microgravity may lead to a number of detrimental effects, including loss of vision. To evaluate the risks associated with transient elevated CO2 levels and design effective countermeasures, doctors must have access to frequent CO2 measurements in the immediate vicinity of individual crew members along with simultaneous measurements of their location in the space environment. To achieve this goal, a small, low-power, wearable system that integrates an accurate CO2 sensor with an ultra-wideband (UWB) radio capable of real-time location estimation and data communication is proposed. This system would be worn by crew members and would automatically gather and transmit sampled sensor data tagged with real-time, high-resolution location information. Under the current proposed effort, a breadboard prototype of such a system will be developed. Although the initial effort is targeted to CO2 monitoring, the concept is applicable to other types of sensors. For the initial effort, existing EV Modular Instrumentation System (MIS) Wireless Sensor Network (WSN) hardware will be leveraged to integrate a low-power CO2 sensor with a commercially available UWB radio system with ranging capability. In addition, potential for integration of this system with EV's Electronic-textile System for the Evaluation of Wearable Technology (E-SEWT) will be evaluated.</p>
- API data.nasa.gov | Last Updated 2018-07-19T03:28:23.000Z
This data set contains calibrated, narrow band filter images (350-950 nm) of Earth acquired by the Deep Impact High Resolution Visible CCD (HRIV) during the EPOCh and Cruise 2 phases of the EPOXI mission. Five sets of observations were acquired on 18-19 March, 28-29 May and 04-05 June 2008 and on 27-28 March and 04-05 October 2009 to characterize Earth as an analog for extrasolar planets. Each observing period lasted approximately 24 hours. HRIV images were acquired once per hour with the filters centered on 350, 750 and 950 nm, whereas the 450-, 550-, 650-, and 850-nm data were taken every 15 minutes. During the observing period in May 2008, the Moon transited across Earth as seen from the spacecraft. On 27 September 2009 during the first attempt of an Earth south polar observation, only seven HRIV frames were acquired before fault protection turned that instrument off; the full sequence was successfully rerun on 04-05 October 2009. Version 2.0 includes the application of a horizontal destriping process and revised electronic crosstalk calibration files.
- API data.nasa.gov | Last Updated 2018-07-18T19:47:44.000Z
This grouping contains the incompressible-flow cases from the 1980-81 Data Library.
- API data.nasa.gov | Last Updated 2018-07-20T07:51:34.000Z
This grouping contains the compressible-flow cases from the 1980-81 Data Library.
- API data.nasa.gov | Last Updated 2018-07-20T07:18:10.000Z
Physical Sciences Inc. and Advanced Solutions, Inc. propose a novel approach for on-orbit assembly of a modular spacecraft using a unique universal, intelligent, electromechanical interface (AUTOCONNECT) on surfaces of individual modules. AUTOCONNECT not only provides mechanical fastening between modules (irrespective of precise alignments and orientations), but also automatically configures electrical connections among modules. Mechanical attachment occurs due to docking and physical contact between modules with sufficient initial momenta. The mass properties of the assembly are determined on orbit and the entire assembly functions as a spacecraft unit. In Phase I we simulated spacecraft assembly in two dimensions using instrumented hexagonal modules supported on air bearings with yaw control provided by a reaction wheel on each module. We demonstrated the feasibility of attachment via AUTOCONNECT, power and data transfer across the interface, and angular orientation control of the assembly. In Phase II, we propose to simulate orbital assembly of a spacecraft configuration as an AUTOCONNECTed assembly of multiple instrumented modules, where each module functions as a spacecraft subsystem or payload, and demonstrate command and control of the entire assembly. Additionally, we will address the system level design issues for AUTOCONNECT-equipped spacecraft modules and the concept of operations for their on-orbit assembly.