Evidence for widespread hydrated minerals on asteroid (101955) Bennu

Early spectral data from the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission reveal evidence for abundant hydrated minerals on the surface of near-Earth asteroid (101955) Bennu in the form of a near-infrared absorption near 2.7 µm and thermal infrared spectral features that are most similar to those of aqueously altered CM-type carbonaceous chondrites. We observe these spectral features across the surface of Bennu, and there is no evidence of substantial rotational variability at the spatial scales of tens to hundreds of metres observed to date. In the visible and near-infrared (0.4 to 2.4 µm) Bennu’s spectrum appears featureless and with a blue (negative) slope, confirming previous ground-based observations. Bennu may represent a class of objects that could have brought volatiles and organic chemistry to Earth

The dynamic geophysical environment of (101955) Bennu based on OSIRIS-REx measurements

The top-shaped morphology characteristic of asteroid (101955) Bennu, often found among fast-spinning asteroids and binary asteroid primaries, may have contributed substantially to binary asteroid formation. Yet a detailed geophysical analysis of this morphology for a fast-spinning asteroid has not been possible prior to the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission. Combining the measured Bennu mass and shape obtained during the Preliminary Survey phase of the OSIRIS-REx mission, we find a notable transition in Bennu’s surface slopes within its rotational Roche lobe, defined as the region where material is energetically trapped to the surface. As the intersection of the rotational Roche lobe with Bennu’s surface has been most recently migrating towards its equator (given Bennu’s increasing spin rate), we infer that Bennu’s surface slopes have been changing across its surface within the last million years. We also find evidence for substantial density heterogeneity within this body, suggesting that its interior is a mixture of voids and boulders. The presence of such heterogeneity and Bennu’s top shape are consistent with spin-induced failure at some point in its past, although the manner of its failure cannot yet be determined. Future measurements by the OSIRIS-REx spacecraft will provide insight into and may resolve questions regarding the formation and evolution of Bennu’s top-shape morphology and its link to the formation of binary asteroids

AN INVESTIGATION INTO THE STABILITIES OF CRUDE OIL EMULSIONS AND COLLOIDAL SILICA SYSTEMS

The effectiveness of enhanced oil recovery techniques depends strongly on the stability of the crude oil emulsions. The ionic nature of the aqueous phase influences emulsion stability and can vary between oil wells. To better understand the influence specific ion effects may have on these systems, the stability was measured using the bottle test for crude oil emulsions in various monovalent and divalent electrolytic solutions. Specific ion effects were not found to have a significant influence on emulsion stability, and restabilization at higher ionic strengths was not observed. Owing to its natural abundance, biocompatibility, and surface modification performance, silica is widely used in industrial applications ranging from surface treatments to medicine and, more recently, to the stabilization of crude oil emulsions. Silica’s effectiveness in these roles is similarly dependent on its colloidal stability characteristics. The aggregation kinetics of bare and sulfonated silica nanoparticles were studied via absorbance measurements. Specific ion effects significantly influenced the colloidal stability of both particles. Restabilization was only observed for the sulfonated silica nanoparticles

Finite Element Analysis of a Hobie 16 Mast and Possible Alternatives

Hobie Cat is one of the most popular sailboat production companies to ever exist, and the Hobie 16 is the most popular boat in the Hobie Cat line-up. The key to Hobie’s success was largely in part to advancements in strong and lightweight materials. This advancement allowed Hobie to achieve record breaking performance in their particular class of boat. The mast of the Hobie 16 is one of the heavier pieces of the craft. The overall mass and center of mass is greatly affected by this component, which begs to question if there may possibly be room for improvement. A sailboat mast is defined as a tall vertical spar, sometimes sectioned, that rises from the keel or deck of a sailing vessel to support the sails and the standing and running rigging. Sailboat masts are long, slender structures. They must be designed to be able to hold the thrust loads that are acting on them from the sails which will differ based on wind conditions. A mast must also be made of a material that will allow it to go through the varying environmental conditions without fatiguing. When designing a sailboat mast a few of the main goals are to have a low center of gravity, be light weight, and also aerodynamically efficient. During this research a Hobie 16 mast design was taken as a baseline design for testing. The current mast on the market weighs between 50–60 lbs. While this is not extremely heavy, the center of gravity is approximately 13.5 feet from the end of the mast. This high center of gravity makes it tough to raise and lower the mast when launching the boat. One important objective in this work is to create a mast that will be easier for the user to raise and lower without sacrificing the structural integrity of the mast. Three masts have been created in solid modeling software, and their performance characteristics have been tested using finite element analysis software ANSYS. Two of the designs are original works, while one is a copy of the original Hobie Cat design. The original design was analyzed, providing baseline data for which to compare the new designs with. In addition to the new designs, all designs have been constructed from three different materials as Aluminum Alloy 6061, Aluminum Alloy 7075 and Acrylic. This allows for comparison of designs and possible new materials. After an in depth analysis of all masts, the recommendation is made that Hobie 16 users would benefit greatly from the use of a tapered mast made of aluminum alloy 7075. Copyright © 2014 by ASM

Finite Element Analysis of a Hobie 16 Mast and Possible Alternatives

Hobie Cat is one of the most popular sailboat production companies to ever exist, and the Hobie 16 is the most popular boat in the Hobie Cat line-up. The key to Hobie’s success was largely in part to advancements in strong and lightweight materials. This advancement allowed Hobie to achieve record breaking performance in their particular class of boat. The mast of the Hobie 16 is one of the heavier pieces of the craft. The overall mass and center of mass is greatly affected by this component, which begs to question if there may possibly be room for improvement. A sailboat mast is defined as a tall vertical spar, sometimes sectioned, that rises from the keel or deck of a sailing vessel to support the sails and the standing and running rigging. Sailboat masts are long, slender structures. They must be designed to be able to hold the thrust loads that are acting on them from the sails which will differ based on wind conditions. A mast must also be made of a material that will allow it to go through the varying environmental conditions without fatiguing. When designing a sailboat mast a few of the main goals are to have a low center of gravity, be light weight, and also aerodynamically efficient. During this research a Hobie 16 mast design was taken as a baseline design for testing. The current mast on the market weighs between 50–60 lbs. While this is not extremely heavy, the center of gravity is approximately 13.5 feet from the end of the mast. This high center of gravity makes it tough to raise and lower the mast when launching the boat. One important objective in this work is to create a mast that will be easier for the user to raise and lower without sacrificing the structural integrity of the mast. Three masts have been created in solid modeling software, and their performance characteristics have been tested using finite element analysis software ANSYS. Two of the designs are original works, while one is a copy of the original Hobie Cat design. The original design was analyzed, providing baseline data for which to compare the new designs with. In addition to the new designs, all designs have been constructed from three different materials as Aluminum Alloy 6061, Aluminum Alloy 7075 and Acrylic. This allows for comparison of designs and possible new materials. After an in depth analysis of all masts, the recommendation is made that Hobie 16 users would benefit greatly from the use of a tapered mast made of aluminum alloy 7075. Copyright © 2014 by ASM

Finite Element Analysis of a Hobie 16 Mast and Possible Alternatives for Improvement

Hobie Cat is one of the most popular sailboat production companies to ever exist, and the Hobie 16 is the most popular boat in the Hobie Cat line-up. The key to Hobie’s success was largely in part to advancements in strong and lightweight materials. This advancement allowed Hobie to achieve record breaking performance in their particular class of boat. The mast of the Hobie 16 is one of the heavier pieces of the craft. The overall mass and center of mass is greatly affected by this component, which begs to question if there may possibly be room for improvement. A sailboat mast is defined as a tall vertical spar, sometimes sectioned, that rises from the keel or deck of a sailing vessel to support the sails and the standing and running rigging. Sailboat masts are long, slender structures. They must be designed to be able to hold the thrust loads that are acting on them from the sails which will differ based on wind conditions. A mast must also be made of a material that will allow it to go through the varying environmental conditions without fatiguing. When designing a sailboat mast a few of the main goals are to have a low center of gravity, be light weight, and also aerodynamically efficient. During this research a Hobie 16 mast design was taken as a baseline design for testing. The current mast on the market weighs between 50–60 lbs. While this is not extremely heavy, the center of gravity is approximately 13.5 feet from the end of the mast. This high center of gravity makes it tough to raise and lower the mast when launching the boat. One important objective in this work is to create a mast that will be easier for the user to raise and lower without sacrificing the structural integrity of the mast. Three masts have been created in solid modeling software, and their performance characteristics have been tested using finite element analysis software ANSYS. Two of the designs are original works, while one is a copy of the original Hobie Cat design. The original design was analyzed, providing baseline data for which to compare the new designs with. In addition to the new designs, all designs have been constructed from three different materials as Aluminum Alloy 6061, Aluminum Alloy 7075 and Acrylic. This allows for comparison of designs and possible new materials. After an in depth analysis of all masts, the recommendation is made that Hobie 16 users would benefit greatly from the use of a tapered mast made of aluminum alloy 7075

Finite Element Analysis of a Hobie 16 Mast and Possible Alternatives for Improvement

Hobie Cat is one of the most popular sailboat production companies to ever exist, and the Hobie 16 is the most popular boat in the Hobie Cat line-up. The key to Hobie’s success was largely in part to advancements in strong and lightweight materials. This advancement allowed Hobie to achieve record breaking performance in their particular class of boat. The mast of the Hobie 16 is one of the heavier pieces of the craft. The overall mass and center of mass is greatly affected by this component, which begs to question if there may possibly be room for improvement. A sailboat mast is defined as a tall vertical spar, sometimes sectioned, that rises from the keel or deck of a sailing vessel to support the sails and the standing and running rigging. Sailboat masts are long, slender structures. They must be designed to be able to hold the thrust loads that are acting on them from the sails which will differ based on wind conditions. A mast must also be made of a material that will allow it to go through the varying environmental conditions without fatiguing. When designing a sailboat mast a few of the main goals are to have a low center of gravity, be light weight, and also aerodynamically efficient. During this research a Hobie 16 mast design was taken as a baseline design for testing. The current mast on the market weighs between 50–60 lbs. While this is not extremely heavy, the center of gravity is approximately 13.5 feet from the end of the mast. This high center of gravity makes it tough to raise and lower the mast when launching the boat. One important objective in this work is to create a mast that will be easier for the user to raise and lower without sacrificing the structural integrity of the mast. Three masts have been created in solid modeling software, and their performance characteristics have been tested using finite element analysis software ANSYS. Two of the designs are original works, while one is a copy of the original Hobie Cat design. The original design was analyzed, providing baseline data for which to compare the new designs with. In addition to the new designs, all designs have been constructed from three different materials as Aluminum Alloy 6061, Aluminum Alloy 7075 and Acrylic. This allows for comparison of designs and possible new materials. After an in depth analysis of all masts, the recommendation is made that Hobie 16 users would benefit greatly from the use of a tapered mast made of aluminum alloy 7075

The Pluto system: Initial results from its exploration by New Horizons

The Pluto system was recently explored by NASA's New Horizons spacecraft, making closest approach on 14 July 2015. Pluto's surface displays diverse landforms, terrain ages, albedos, colors, and composition gradients. Evidence is found for a water-ice crust, geologically young surface units, surface ice convection, wind streaks, volatile transport, and glacial flow. Pluto's atmosphere is highly extended, with trace hydrocarbons, a global haze layer, and a surface pressure near 10 microbars. Pluto's diverse surface geology and long-term activity raise fundamental questions about how small planets remain active many billions of years after formation. Pluto's large moon Charon displays tectonics and evidence for a heterogeneous crustal composition, its north pole displays puzzling dark terrain. Small satellites Hydra and Nix have higher albedos than expected.Comment: 8 pages - Initial Science paper from NASA's New Horizons Pluto Encounte

The Pluto system: Initial results from its exploration by New Horizons

The Pluto system was recently explored by NASA's New Horizons spacecraft, making closest approach on 14 July 2015. Pluto's surface displays diverse landforms, terrain ages, albedos, colors, and composition gradients. Evidence is found for a water-ice crust, geologically young surface units, surface ice convection, wind streaks, volatile transport, and glacial flow. Pluto's atmosphere is highly extended, with trace hydrocarbons, a global haze layer, and a surface pressure near 10 microbars. Pluto's diverse surface geology and long-term activity raise fundamental questions about how small planets remain active many billions of years after formation. Pluto's large moon Charon displays tectonics and evidence for a heterogeneous crustal composition; its north pole displays puzzling dark terrain. Small satellites Hydra and Nix have higher albedos than expected