Time filter

Source Type

San Antonio, TX, United States

Southwest Research Institute , headquartered in San Antonio, Texas, is one of the oldest and largest independent, nonprofit, applied research and development organizations in the United States. Founded in 1947 by oil businessman Thomas Slick, Jr., SwRI provides contract research and development services to government and industrial clients.The institute consists of 11 technical divisions that offer multidisciplinary, problem-solving services in a variety of areas in engineering and the physical science. More than 2,000 projects are active at the institute at any given time. These projects are funded almost equally between the government and commercial sectors. At the close of fiscal year 2013, the SwRI staff numbered 2,845 employees and total revenue was $592 million. The institute provided $6.7 million to fund innovative research through its internally sponsored R&D program.Partial listing of research areas includes space science and engineering; automation, robotics, and intelligent systems; avionics and support systems; bioengineering; chemistry and chemical engineering; corrosion and electrochemistry; earth and planetary science; emissions research; engineering mechanics; fire technology; fluid systems and machinery dynamics; and fuels and lubricants. Additional areas include geochemistry and mining engineering; hydrology and geohydrology; materials science and fracture mechanics; modeling and simulation; nondestructive evaluation; oil and gas exploration; pipeline technology; surface modification and coatings; and vehicle, engine, and powertrain design, research, and development.SwRI initiates contracts with clients based on consultations and prepares a formal proposal outlining the scope of work. Subject to client wishes, programs are kept confidential. As part of a long-held tradition, patent rights arising from sponsored research are often assigned to the client. SwRI generally retains the rights to institute-funded advancements. The institute’s headquarters occupy more than two million square feet of office and laboratory space on more than 1,200 acres in San Antonio. SwRI has technical offices and laboratories in Boulder, Colorado; Ann Arbor, Michigan; Warner-Robins, Georgia; Ogden, Utah; Oklahoma City, Oklahoma; Rockville, Maryland; Minneapolis, Minnesota; Beijing, China; and other locations. The institute also provides environmental monitoring expertise at a munitions disposal site at the Umatilla Army Depot in Hermiston, Oregon.SwRI’s mission statement is, "Benefiting government, industry and the public through innovative science and technology." Two of its core values are independence and impartiality. Wikipedia.

Canup R.M.,Southwest Research Institute
Astronomical Journal | Year: 2011

It is generally believed that Charon was formed as a result of a large, grazing collision with Pluto that supplied the Pluto-Charon system with its high angular momentum. It has also been proposed that Pluto's small outer moons, Nix and Hydra, formed from debris from the Charon-forming impact, although the viability of this scenario remains unclear. Here I use smooth particle hydrodynamics impact simulations to show that it is possible to simultaneously form an intact Charon and an accompanying debris disk from a single impact. The successful cases involve colliding objects that are partially differentiated prior to impact, having thin outer ice mantles overlying a uniform composition rock-ice core. The composition of the resulting debris disks varies from a mixture of rock and ice (similar to the bulk composition of Pluto and Charon) to a pure ice disk. If Nix and Hydra were formed from such an impact-generated disk, their densities should be less than or similar to that of Charon and Pluto, and the small moons could be composed entirely of ice. If they were instead formed from captured material, a mixed rock-ice composition and densities similar to that of Charon and Pluto would be expected. Improved constraints on the properties of Nix and Hydra through occultations and/or the New Horizons encounter may thus help to distinguish between these two modes of origin, particularly if the small moons are found to have ice-like densities. © 2011. The American Astronomical Society. Source

Nesvorny D.,Southwest Research Institute
Astrophysical Journal Letters | Year: 2011

Studies of solar system formation suggest that the solar system's giant planets formed and migrated in the protoplanetary disk to reach the resonant orbits with all planets inside ∼15 AU from the Sun. After the gas disk's dispersal, Uranus and Neptune were likely scattered by the gas giants, and approached their current orbits while dispersing the transplanetary disk of planetesimals, whose remains survived to this time in the region known as the Kuiper Belt. Here we performed N-body integrations of the scattering phase between giant planets in an attempt to determine which initial states are plausible. We found that the dynamical simulations starting with a resonant system of four giant planets have a low success rate in matching the present orbits of giant planets and various other constraints (e.g., survival of the terrestrial planets). The dynamical evolution is typically too violent, if Jupiter and Saturn start in the 3:2 resonance, and leads to final systems with fewer than four planets. Several initial states stand out in that they show a relatively large likelihood of success in matching the constraints. Some of the statistically best results were obtained when assuming that the solar system initially had five giant planets and one ice giant, with the mass comparable to that of Uranus and Neptune, and which was ejected to interstellar space by Jupiter. This possibility appears to be conceivable in view of the recent discovery of a large number of free-floating planets in interstellar space, which indicates that planet ejection should be common. © 2011. The American Astronomical Society. All rights reserved.. Source

Grimm R.E.,Southwest Research Institute
Journal of Geophysical Research E: Planets | Year: 2013

The Moon's Procellarum KREEP Terrane (PKT) is distinguished by unique geochemistry and extended volcanic history. Previous thermal-conduction models using enhanced radionuclide abundances in subcrustal potassium, rare earth elements, and phosphorus (KREEP) predicted the existence of a contemporary upper-mantle melt zone as well as heat flow consistent with Apollo measurements. Here I show that such models also predict large gravity or topography anomalies that are not observed. If the topography is suppressed by a rigid lithosphere, it is possible to eliminate the gravity anomaly and still match heat flow by completely fractionating the excess radionuclides into a thin crust. This implies that upper-mantle heat sources for mare volcanism were spatially discontinuous or transient and that radionuclides defining the PKT are not necessarily directly related to mare volcanic sources. However, the mantle temperature of a crustally fractionated PKT is insufficient to match the observed electrical conductivity: globally enhanced mantle heating or a thick megaregolith may be required. Alternatively, upper-mantle enrichment in iron, hydrogen, or aluminum can provide the requisite conductivity. Iron is the most plausible: the derived lower limit to the upper-mantle magnesium number 75-80% is consistent with seismic modeling. Regardless of the specific mechanism for electrical-conductivity enhancement, the overall excellent match to simple thermal-conduction models indicates that the lunar upper mantle is not convecting at present. © 2012. American Geophysical Union. All Rights Reserved. Source

Young L.A.,Southwest Research Institute
Astrophysical Journal Letters | Year: 2013

Since the last Pluto volatile transport models were published in 1996, we have (1) new stellar occultation data from 2002 and 2006-2012 that show roughly twice the pressure as the first definitive occultation from 1988, (2) new information about the surface properties of Pluto, (3) a spacecraft due to arrive at Pluto in 2015, and (4) a new volatile transport model that is rapid enough to allow a large parameter-space search. Such a parameter-space search coarsely constrained by occultation results reveals three broad solutions: a high-thermal inertia, large volatile inventory solution with permanent northern volatiles (PNVs; using the rotational north pole convention); a lower thermal-inertia, smaller volatile inventory solution with exchanges of volatiles between hemispheres and a pressure plateau beyond 2015 (exchange with pressure plateau, EPP); and solutions with still smaller volatile inventories, with exchanges of volatiles between hemispheres and an early collapse of the atmosphere prior to 2015 (exchange with early collapse, EEC). PNV and EPP are favored by stellar occultation data, but EEC cannot yet be definitively ruled out without more atmospheric modeling or additional occultation observations and analysis. © 2013. The American Astronomical Society. All rights reserved. Source

Spencer J.R.,Southwest Research Institute | Nimmo F.,University of California at Santa Cruz
Annual Review of Earth and Planetary Sciences | Year: 2013

Enceladus, one of the mid-sized icy moons of Saturn, has an importance to planetary science far greater than its modest 504-km diameter would suggest. Intensive exploration of Enceladus by the Cassini Saturn orbiter has revealed that it is the only known icy world in the solar system with ongoing deep-seated geological activity. Active tectonic fractures at Enceladus's south pole, dubbed "tiger stripes," warmed by internal tidally generated heat, spew supersonic jets of water vapor, other gases, and ice particles into circum-Saturnian space. A subsurface saltwater sea probably exists under the south pole, between the ice shell and the silicate core. Because of evidence that liquid water is probably present at the jet sources, Enceladus is also of great astrobiological interest as a potential habitat for life. © Copyright ©2013 by Annual Reviews. All rights reserved. Source

Discover hidden collaborations