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In this video clip, the NASA Television show, Mission Update,' hosted by Pat Ryan, provides a synopsis of the ninth day of the STS-72 Space Shuttle mission. The scheduled activities, their times, and who will be conducting them are highlighted along with various film clips showing different aspects of the mission.
The NASA Television show, Mission Update,' hosted by Pat Ryan, provides a synopsis of the eighth day of the STS-72 Space Shuttle mission in this video clip. The scheduled activities, their times, and who will be conducting them are highlighted along with various film clips from the beginning of the mission to date.
This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 96, held at Los Alamos National Laboratory, Los Alamos, New Mexico on October 27-30, 1996. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.
This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 97, held at Boeing Commercial Airplane Group, Seattle, Washington, on November 2-5, 1997. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.
Six years ago, we compared the climate sensitivity of 19 atmospheric general circulation models and found a roughly threefold variation among the models; most of this variation was attributed to differences in the models' depictions of cloud feedback. In an update of this comparison, current models showed considerably smaller differences in net cloud feedback, with most producing modest values. There are, however, substantial differences in the feedback components, indicating that the models still have physical disagreements.
This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 98. held at Brookhaven National Laboratory, Upton, New York on November 1-4, 1998.
NASA is developing the Center-TBACON Advisory System (CTAS), a set of Air Traffic Management (ATM) Decision Support Tools (DST) to enable controllers to increase airspace capacity and flight efficiency. A crucial component of the CTAS, or any ATM DST, is the computation of the time-of-flight of aircraft along flight path segments which requires accurate knowledge of the wind through which the aircraft are flying. CTAS currently uses wind information from the Rapid Update Cycle (RUC), a numerical prediction model run operationally by the National Weather Service (NWS) National Center for Environmental Prediction (NCEP). There exists near real-time wind observations from commercial aircraft that can be used to increase the accuracy of the RUC wind forecasts via the FAA Integrated Terminal Weather System (ITWS) Terminal Winds (TW) algorithm. This report presents a study based on the application of the ITWS TW algorithm as an improvement to the baseline RUC product. Terminal Winds generally does not support the full Center airspace; the domain of the prototype MIT/LLITWS TW system was increased to cover the Denver Center airspace to support this study. This study has three goals: 1) determine the errors in the baseline 60-kilometer resolution RUC forecast wind fields relative to the needs of en route DSTs such as CTAS; 2) determine the benefit of using the TW algorithm to refine the RUC forecast wind fields with near real-tlme Meteorological Data Collection and Reporting System (MDCRS) aircraft reports, and 3) identify factors that influence wind field errors in order to improve accuracy and estimate errors in real time. The data for this study were collected over a one-year period for the Denver Center airspace and over one miIlion verification observations were used. This study is part of a larger effort funded by NASA which includes the NOAA/FSL.
This study has been completed, and the following is an update of the results as published. Pregnant rats were flown on the Space Shuttle in the NIH.R I mission for 11 days, and pregnant control rats were maintained in animal enclosure modules in a ground-based chamber under conditions approximating those in flight. Additional controls were in standard housing. The effects of the flight on immunological parameters (including blastogenesis, interferon-gamma production, response to colony stimulating factor and total immunoglobulin levels) of dams, fetuses, and pups was determined.
The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every six months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.
We are continuing our ongoing study of cosmogenic nuclides in Antarctic meteorites. In addition to the studies of exposure histories of meteorites, we study terrestrial ages and pairing of Antarctic meteorites and desert meteorites. Terrestrial ages of Antarctic meteorites provide information on meteorite accumulation mechanisms, mean weathering lifetimes, and influx rates. The determination of Cl-36(half-life=3.01 x 10(exp 5) y) terrestrial ages is one of our long-term on-going projects, however, in many instances neither Cl-36 or C-14 (5,730 y) yields an accurate terrestrial age. Using Ca-14 (1.04 x 10(exp 5) y) for terrestrial age determinations solves this problem by filling the c,ap in half-life between 14-C and Cl-36 ages. We are now applying the new Ca-41- Cl-36 terrestrial age method as well as the Cl-36-Be-10 method to Antarctic meteorites. Our measurements and C-14 terrestrial age determinations by the University of Arizona group are always complementary. We have measured Cl-36 in over 270 Antarctic meteorites since our previous compilation of terrestrial ages. Since a large number of meteorites have been recovered from many different icefields in Antarctica, we continue to survey the trends of terrestrial ages for different icefields. We have also measured detailed terrestrial ages vs. sample locations for Allan Hills, Elephant Moraine, and Lewis Cliff Icefields, where meteorites have been found with very long ages. The updated histograms of terrestrial ages of meteorites from the Allan Hills Main Icefield and Lewis Cliff Icefield are shown. These figures include C-14 ages obtained by the University of Arizona group. Pairs of meteorites are shown as one object for which the age is the average of all members of the same fall. The width of the bars represents 70,000 years, which was a typical uncertainty for Cl-36 ages. We reduced the uncertainty of terrestrial age determinations to approx. 40,000 years by using pairs of nuclides such as Ca-41-Cl-36 or Cl-36-Be-10. Meteorites found at the Allan Hills Icefields are much older than any other meteorites. The terrestrial ages cover a wide range and are as old as 2 My. Many of the Lewis Cliff meteorites are as old as the Allan Hills meteorites. So far, no clear correlation has been found between the terrestrial ages and the locations of the Lewis Cliff meteorites.
This eighth Compendium continues the previous work of Nichols, et al, on single event effects (SEE) first published in 1985. Because the compendium has grown so voluminous, this update only presents data not publised in previous compendia.
The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every 6 months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition of the NASA Thesaurus. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.
Analysis of melt extent on the Greenland ice sheet is updated to span the time period 1979-1999 is examined along with its spatial and temporal variability using passive microwave satellite data. In order to acquire the full record, the issue of continuity between previous passive microwave sensors (SMMR, SSM/I F-8, and SSM/I F-11), and the most recent SSM/I F-13 sensor is addressed. The F-13 Cross-polarized gradient ratio (XPGR) melt-classification threshold is determined to be -0.0154. Results show that for the 21-year record, an increasing melt trend of nearly 1 %/yr is observed, and this trend is driven by conditions on in the western portion of the ice sheet, rather than the east, where melt appears to have decreased slightly. Moreover, the eruption of Mt. Pinatubo in 1991 is likely to have had some impact the melt, but not as much as previously suspected. The 1992 melt anomaly is 1.7 standard deviations from the mean. Finally, the relationship between coastal temperatures and melt extent suggest an increase in surface runoff contribution to sea level of 0.31 mm/yr for a 1 C temperature rise.
This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 99, held at DaimlerChrysler, Auburn Hills, Michigan, from October 31 - November 3, 1999.
The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every six months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition of the NASA Thesaurus. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.
We present an updated database of coronae on Venus, increasing the number of features from 336 to 523. Additional information is contained in the original extended abstract.
The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every six months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition of the NASA Thesaurus. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.
This viewgraph presentation gives an overview of the X-33 program update, including details on program objectives and plans, the X-33 configuration, technologies used, and X-33 assembly and test status.