Looking at Ceres

At last week's Lunar and Planetary Science Conference, I enjoyed a large number of talks about Ceres, which Dawn is now orbiting at an altitude of merely 385 kilometers. Several sessions worth of talks considered a wealth of new data that has been acquired since the last time I attended scientific sessions on Dawn, at lower altitudes and hence more detail. All that freshly acquired data made for talks bursting with pretty pictures and data but relatively thin on interpretation and with little coordination (yet) across data sets, which makes them a bit hard to summarize briefly. Deputy principal investigator Carol Raymond summed the situation up well at the press briefing: "Clearly, we have a lot of work to do to put together a self-consistent story among all these different data sets."

link.

Simulating the Atmosphere of the Martian Northern Hemisphere

The variability, structure and energy conversion of the northern hemisphere traveling waves simulated in a Mars general circulation model

Authors:

Wang et al

Abstract:

Investigations of the variability, structure and energetics of the m = 1−3 traveling waves in the northern hemisphere of Mars are conducted with the MarsWRF general circulation model. Using a simple, annually repeatable dust scenario, the model reproduces many general characteristics of the observed traveling waves. The simulated m = 1 and m = 3 traveling waves show large differences in terms of their structures and energetics. For each representative wave mode, the geopotential signature maximizes at a higher altitude than the temperature signature, and the wave energetics suggests a mixed baroclinic-barotropic nature. There is a large contrast in wave energetics between the near-surface and higher altitudes, as well as between the lower latitudes and higher latitudes at high altitudes. Both barotropic and baroclinic conversions can act as either sources or sinks of eddy kinetic energy. Band-pass filtered transient eddies exhibit strong zonal variations in eddy kinetic energy and various energy transfer terms. Transient eddies are mainly interacting with the time mean flow. However, there appear to be non-negligible wave-wave interactions associated with wave mode transitions. These interactions include those between traveling waves and thermal tides and those among traveling waves.

Planet Nine Might be Smaller and Closer than Brown et al Think

Observational Constraints on Planet Nine: Astrometry of Pluto and Other Trans-Neptunian Objects

Authors:

Holman et al

Abstract:

We use astrometry of Pluto and other TNOs to constrain the sky location, distance, and mass of the possible additional planet (Planet Nine) hypothesized by Batygin and Brown (2016). We find that over broad regions of the sky, the inclusion of a massive, distant planet degrades the fits to the observations. However, in other regions, the fits are significantly improved by the addition of such a planet. Our best fits suggest a planet that is either more massive or closer than argued for by Batygin and Brown (2016) based on the orbital distribution of distant trans-neptunian objects (or by Fienga et al. (2016) based on range measured to the Cassini spacecraft). The trend to favor larger and closer perturbing planets is driven by the residuals to the astrometry of Pluto, remeasured from photographic plates using modern stellar catalogs (Buie and Folkner 2015), which show a clear trend in declination, over the course of two decades, that drive a preference for large perturbations. Although this trend may be the result of systematic errors of unknown origin in the observations, a possible resolution is that the declination trend may be due to perturbations from a body, additional to Planet Nine , that is closer to Pluto, but less massive than, Planet Nine .

3d Printing Called Crucial to Hypersonic Weapons

The race is on to build hypersonic weapons, missiles that blow through a target’s defenses at more than five times the speed of sound. Or should that be “the race to grow hypersonic weapons”? It turns out an unrelated cutting-edge technology, 3D printing, may be the key to making hypersonics work.

The whole aerospace world is intrigued by so-called additive manufacturing — especially for government and/or unmanned applications not subject to laborious FAA safety testing on new technology. NASA has a 3D printer on the International Space Station; the Navy has tested one on a ship. Several rocket engine companies have built key components for these exemplars of high tech using 3D printing; at Elon Musk’s radical venture SpaceX, for example, “they have a big 3D printer [and] they are making parts that are in production rocket engines right now,” said aerospace consultant Kevin Michaels, a vice-president at ICF International.

The ability to build up components dot by dot, layer by layer, can be helpful in making conventional aircraft, spacecraft, and missiles. But when it comes to making hypersonic systems, which require exotic materials and strangely shaped components that conventional methods can’t handle, 3D printing may be essential.

link.

US Navy Nuclear Submarine Plans

Electric Boat has been selected to build the Ohio Replacement nuclear ballistic missile submarines while  Both Electric Boat and Newport News will continue to build the Virginia class nuclear attack submarine.  Maybe.

All American subs will be upgraded to become acoustically stealthier.

Dynamic Antarctic ice sheet during the early to mid-Miocene

Dynamic Antarctic ice sheet during the early to mid-Miocene

Authors:

Gasson et al

Abstract:

Geological data indicate that there were major variations in Antarctic ice sheet volume and extent during the early to mid-Miocene. Simulating such large-scale changes is problematic because of a strong hysteresis effect, which results in stability once the ice sheets have reached continental size. A relatively narrow range of atmospheric CO2 concentrations indicated by proxy records exacerbates this problem. Here, we are able to simulate large-scale variability of the early to mid-Miocene Antarctic ice sheet because of three developments in our modeling approach. (i) We use a climate–ice sheet coupling method utilizing a high-resolution atmospheric component to account for ice sheet–climate feedbacks. (ii) The ice sheet model includes recently proposed mechanisms for retreat into deep subglacial basins caused by ice-cliff failure and ice-shelf hydrofracture. (iii) We account for changes in the oxygen isotopic composition of the ice sheet by using isotope-enabled climate and ice sheet models. We compare our modeling results with ice-proximal records emerging from a sedimentological drill core from the Ross Sea (Andrill-2A) that is presented in a companion article. The variability in Antarctic ice volume that we simulate is equivalent to a seawater oxygen isotope signal of 0.52–0.66‰, or a sea level equivalent change of 30–36 m, for a range of atmospheric CO2 between 280 and 500 ppm and a changing astronomical configuration. This result represents a substantial advance in resolving the long-standing model data conflict of Miocene Antarctic ice sheet and sea level variability.

Carbon cycle history across the Jurassic–Cretaceous boundary

Carbon cycle history through the Jurassic–Cretaceous boundary: A new global δ13C stack

Authors:

Price et al

Abstract:

We present new carbon and oxygen isotope curves from sections in the Bakony Mts. (Hungary), constrained by biostratigraphy and magnetostratigraphy in order to evaluate whether carbon isotopes can provide a tool to help establish and correlate the last system boundary remaining undefined in the Phanerozoic as well provide data to better understand the carbon cycle history and environmental drivers during the Jurassic–Cretaceous interval. We observe a gentle decrease in carbon isotope values through the Late Jurassic. A pronounced shift to more positive carbon isotope values does not occur until the Valanginian, corresponding to the Weissert event. In order to place the newly obtained stable isotope data into a global context, we compiled 31 published and stratigraphically constrained carbon isotope records from the Pacific, Tethyan, Atlantic, and Boreal realms, to produce a new global δ13C stack for the Late Oxfordian through Early Hauterivian interval. Our new data from Hungary is consistent with the global δ13C stack. The stack reveals a steady but slow decrease in carbon isotope values until the Early Valanginian. In comparison, the Late Jurassic–Early Cretaceous δ13C curve in GTS 2012 shows no slope and little variation. Aside from the well-defined Valanginian positive excursion, chemostratigraphic correlation durSchning the Jurassic–Cretaceous boundary interval is difficult, due to relatively stable δ13C values, compounded by a slope which is too slight. There is no clear isotopic marker event for the system boundary. The long-term gradual change towards more negative carbon isotope values through the Jurassic–Cretaceous transition has previously been explained by increasingly oligotrophic condition and lessened primary production. However, this contradicts the reported increase in 87Sr/86Sr ratios suggesting intensification of weathering (and a decreasing contribution of non-radiogenic hydrothermal Sr) and presumably a concomitant rise in nutrient input into the oceans. The concomitant rise of modern phytoplankton groups (dinoflagellates and coccolithophores) would have also led to increased primary productivity, making the negative carbon isotope trend even more notable. We suggest that gradual oceanographic changes, more effective connections and mixing between the Tethys, Atlantic and Pacific Oceans, would have promoted a shift towards enhanced burial of isotopically heavy carbonate carbon and effective recycling of isotopically light organic matter. These processes account for the observed long-term trend, interrupted only by the Weissert event in the Valanginian.

University of Liverpool have developed computer models of the bodies of sauropod dinosaurs

Scientists from the University of Liverpool have developed computer models of the bodies of sauropod dinosaurs to examine the evolution of their body shape.

Sauropod dinosaurs include the largest land animals to have ever lived. Some of the more well-known sauropods include Diplodocus, Apatosaurus and Brontosaurus. They are renowned for their extremely long necks, long tails as well as four thick, pillar-like legs and small heads in relation to their body.

To date, however, there have been only limited attempts to examine how this unique body-plan evolved and how it might be related to their gigantic body size. Dr Karl Bates from the University's Department of Musculoskeletal Biology and his colleagues used three-dimensional computer models reconstructing the bodies of sauropod dinosaurs to analyse how their size, shape and weight-distribution evolved over time.

link.

Changes in environmental stresses and eukaryotes during the Early Triassic to the early Middle Triassic

Secular changes in environmental stresses and eukaryotes during the Early Triassic to the early Middle Triassic

Authors:

Saito et al

Abstract:

The Early Triassic, following the end-Permian mass extinction, was an interval of severe low diversity. Increasing amounts of evidence demonstrate that variable environmental stresses were widespread and intense after the end-Permian mass extinction. Here we report biomarkers from lowest Triassic to lower Middle Triassic strata in South China (Qingyan and Chaohu sections), including biomarkers for environmental stress (2-methyl hopane index) and eukaryotic algae (steranes and C21n-alkylbenzene ratio). Using the 2-methyl hopane index, we detected the persistence of environmental stress during most of the Early Triassic. Using steranes and the C21n-alkylbenzene ratio, we found a gradual increase in the biomass of eukaryotic algae during the Early to early Middle Triassic. A decrease in environmental stress in the Qingyan section (Leidapo Member) during the early Middle Triassic was synchronous with the “explosion” of the Qingyan Biota, which is characterized by a high abundance and diversity of invertebrate marine animals. Because the environmental stresses revealed by the 2-methyl hopane index encompass various factors (e.g., pH and temperature), we cannot identify the exact stresses at that time; however, our results reflect the amelioration of harsh environments for life during the interval of complete biotic recovery.

Scuffle in the South China Sea #36

The HQ-9 antiship missile emplacements by the Chinese are upping the ante in the South China Sea's tensions.  Pictures and video are here.  China has defended its placement of the missiles now.

The clashes of China and Indonesia are looked at here.

The positions of Australia and China with regards to the South China Sea are explored here.

The US has stated the air strips made by the Chinese on their reclaimed islands are definitely intended for military aircraft.

The Philippines is considering purchasing submarines due to the tensions in the South China Sea.

Vietnam has expressed interest in the Su-35s and also S-3 Vikings from the US.

Ukraine War Update: да, да. Они являются марионетками носка

Russia is running a "shadow government" in rebel-held territories of eastern Ukraine under the control of the FSB intelligence service, German daily Bild reported Wednesday, citing minutes from an official commission.

The report said that basic administrative functions of the cities of Donetsk and Lugansk are being run by six working groups at five Russian ministries.

The officials, who manage areas including tax law, transport infrastructure and the establishment of an electricity market, work under the auspices of the FSB and answer to Russian Deputy Prime Minister Dmitry Kozak, a close ally of President Vladimir Putin, according to the minutes cited in Bild.

"It is notable that no members of the self-declared people's republics in eastern Ukraine are on the commission," Bild said.

"They are simply informed about its findings and their political implementation."

link.

SETI Talk: On the Shores of Titan's Farthest Sea

The Predicted Interaction of Lava and Glaciers on Early Mars

Lava heating and loading of ice sheets on early Mars: Predictions for meltwater generation, groundwater recharge, and resulting landforms

Authors:

Cassanelli et al

Abstract:

Recent modeling studies of the early Mars climate predict a predominantly cold climate, characterized by the formation of regional ice sheets across the highland areas of Mars. Formation of the predicted “icy highlands” ice sheets is coincident with a peak in the volcanic flux of Mars involving the emplacement of the Late Noachian – Early Hesperian ridged plains unit. We explore the relationship between the predicted early Mars “icy highlands” ice sheets, and the extensive early flood volcanism to gain insight into the surface conditions prevalent during the Late Noachian to Early Hesperian transition period. Using Hesperia Planum as a type area, we develop an ice sheet lava heating and loading model. We quantitatively assess the thermal and melting processes involved in the lava heating and loading process following the chronological sequence of lava emplacement. We test a broad range of parameters to thoroughly constrain the lava heating and loading process and outline predictions for the formation of resulting geological features. We apply the theoretical model to a study area within the Hesperia Planum region and assess the observed geology against predictions derived from the ice sheet lava heating and loading model. Due to the highly cratered nature of the Noachian highlands terrain onto which the volcanic plains were emplaced, we predict highly asymmetrical lava loading conditions. Crater interiors are predicted to accumulate greater thicknesses of lava over more rapid timescales, while in the intercrater plains, lava accumulation occurs over longer timescales and does not reach great thicknesses. We find that top-down melting due to conductive heat transfer from supraglacial lava flows is generally limited when the emplaced lava flows are less than ∼10 m thick, but is very significant at lava flow thicknesses of ∼100 m or greater. We find that bottom-up cryosphere and ice sheet melting is most likely to occur within crater interiors where lavas accumulate to a sufficient thickness to raise the ice-melting isotherm to the base of the superposed lavas. In these locations, if lava accumulation occurs rapidly, bottom-up melting of the ice sheet can continue, or begin, after lava accumulation has completed in a process we term “deferred melting”. Subsurface mass loss through melting of the buried ice sheets is predicted to cause substantial subsidence in the superposed lavas, leading to the formation of associated collapse features including fracture systems, depressions, surface faulting and folding, wrinkle-ridge formation, and chaos terrain. In addition, if meltwater generated from the lava heating and loading process becomes trapped at the lava flow margins due to the presence of impermeable confining units, large highly pressurized episodic flooding events could occur. Examination of the study area reveals geological features which are generally consistent with those predicted to form as a result of the ice sheet lava heating and loading process, suggesting the presence of surface snow and ice during the Late Noachian to Early Hesperian period.

Could Planet Nine Have Formed in its Current Orbit

Making Planet Nine: Pebble Accretion at 250--750 AU in a Gravitationally Unstable Ring

Authors:

Kenyon et al

Abstract:

We investigate the formation of icy super-Earth mass planets within a gravitationally unstable ring of solids orbiting at 250-750 AU around a 1 solar mass star. Coagulation calculations demonstrate that a system of a few large oligarchs and a swarm of pebbles generates a super-Earth within 100-200 Myr at 250 AU and within 1-2 Gyr at 750 AU. Systems with more than ten oligarchs fail to yield super-Earths over the age of the solar system. As these systems evolve, destructive collisions produce detectable debris disks with luminosities of 10−5 to 10−3 relative to the central star.

US Army Looking to More Than Double Range of 155mm Howitzers

On March 19, U.S. Marine Corps staff sergeant Louis Cardin, a field artilleryman assigned to the 26th Marine Expeditionary Unit, died during an attack on Fire Base Bell outside of Makhmur, Iraq. Coincidentally, the U.S. Army is hard at work developing a farther-firing howitzer that could help keep artillery troops out of range of enemy forces.

The Army is cooking up a suite of improvements could double the range of the existing M-777 howitzer. Right now the 155-millimeter gun, in service with the Army and Marines, can lob shells at targets up to 18 miles away.

[...]

The modifications add fewer than 1,000 pounds of extra weight onto the older howitzers. The updates include improvements that will help gunners fire more accurately plus a mechanism to automatically load rounds into the gun.

The biggest change is the addition of new barrel that’s six feet longer. The longer M-777ER should be able to hit enemy forces more than 43 miles away. And with more powerful propellant charges and rocket-assisted shells, crews might be able to increase that range even more in the near future.

link.

US Navy Progress Report to Congress on Railgun & Laser Weapon Development

link.

Marine Biota was Brought into Songliao Lake by Marine Incursions During the Late Cretaceous

Late Cretaceous marine fossils and seawater incursion events in the Songliao Basin, NE China

Authors:

Xi et al

Abstract:

The Songliao Basin is the largest non-marine oil-bearing basin in China. Because of the absence of substantial evidence, the hypothesis of seawater incursion events into the Songliao Basin remains controversial. The presence of marine fossils could provide direct proof to support this supposition. Here, we report new discoveries of foraminifera, calcareous nannofossils, brackish dinoflagellates, and other marine and brackish-water fossils to support the suggestion of seawater incursion events in the Songliao Basin. Relatively abundant benthic and planktonic foraminifera, calcareous nannofossils, marine and brackish-water dinoflagellates, fish, and bivalves have been discovered in Members 1 and 2 of the Nenjiang Formation, a few foraminifera and brackish-water dinoflagellates have been found in the lower Qingshankou Formation, and just a few brackish-water bivalves have been found in the uppermost Qingshankou Fm. Based on the presence of marine molecular fossils and other evidence, we suggest that relatively large seawater incursion events occurred during the sedimentation of the lower Nenjiang Fm., relatively smaller seawater incursions occurred during the deposition of the lower Qingshankou Fm., and possibly a very small seawater incursion occurred during the sedimentation of the uppermost Qingshankou Fm. These seawater incursion events in the Songliao Basin were controlled by regional tectonic activity, evolution of the palaeo Songliao Lake, and global sea level change. These periodic seawater incursions brought marine biota into the palaeo Songliao Lake.

Preparing for the end of the Cassini Mission

SETI Institute researcher Matt Tiscareno will continue to be on the front lines as the famed Cassini spacecraft embarks on its final mission. NASA has announced that Tiscareno will be a Participating Scientist as Cassini prepares to take the best images of Saturn's rings ever made.

Since 2011, the Cassini Project has selected Participating Scientists to enhance the scientific return of the Cassini mission by broadening the community of researchers taking part in the analysis and interpretation of data. Tiscareno began working with the Cassini mission as a postdoc in 2004, and was first selected as a Participating Scientist in 2012. He is one of four such researchers selected this year by NASA.

Already among the most successful spacecraft missions in history – one whose discoveries have ranged from the geysers of Enceladus to the storms of Saturn, the seas of Titan, and enigmatic features in the rings – Cassini will spend its last year performing a "Grand Finale." It will repeatedly dive close to the rings and the planet for nearly a year, before finally plunging into Saturn in September 2017.

In addition to close-range measurements of Saturn's gravity and magnetic fields (both of which yield insights into the gas giant's interior structure), Cassini will directly sample the atmosphere and measure the mass of the rings. It will also make repeated passes very close to the rings – at distances only a few times the diameter of Earth. In such close proximity, Cassini can garner images with two to three times better resolution than those obtained during the main part of the mission.

link.

Melas Chasma MAY Have had Prolonged Periods of Near Surface Water

Implications for the aqueous history of southwest Melas Chasma, Mars as revealed by interbedded hydrated sulfate and Fe/Mg-smectite deposits

Authors:

Liu et al

Abstract:

Using visible and near infrared data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), we identified a sequence of hydrated sulfates and Fe/Mg-smectites in southwest Melas Chasma. Specifically, these hydrated sulfate and semectite deposits are interbedded and have been highly deformed. Equilibrium thermodynamic calculations of coupled basalt weathering and fluid evaporation predict that sequential formation of Fe/Mg-smectites and sulfate evaporites in similar quantities, as observed in the interbedded smectite-sulfate sequences, is chemically plausible. The Fe/Mg-smectite-sulfate deposits may have thus formed through in situ basalt weathering and fluid evaporation, although an origin involving repeated cycles of transport and deposition of detrital clays by a neutral fluid containing Mg and SO4 and subsequent evaporation cannot be ruled out. If the Fe/Mg-smectites are authigenic, the Hesperian (or younger) age Melas Chasma would have experienced prolonged periods with near-surface water, providing potentially habitable conditions.

Is Planet Nine a Scattered Giant From the Inner Solar System?

Making Planet Nine: A Scattered Giant in the Outer Solar System

Authors:

Bromley et al

Abstract:

Correlations in the orbits of several minor planets in the outer solar system suggest the presence of a remote, massive Planet Nine. With at least ten times the mass of the Earth and a perihelion well beyond 100 AU, Planet Nine poses a challenge to planet formation theory. Here we expand on a scenario in which the planet formed closer to the Sun and was gravitationally scattered by Jupiter or Saturn onto a very eccentric orbit in an extended gaseous disk. Dynamical friction with the gas then allowed the planet to settle in the outer solar system. We explore this possibility with a set of numerical simulations. Depending on how the gas disk evolves, scattered super-Earths or small gas giants settle on a range of orbits, with perihelion distances as large as 300 AU. Massive disks that clear from the inside out on million-year time scales yield orbits that allow a super-Earth or gas giant to shepherd the minor planets as observed. A massive planet can achieve a similar orbit in a persistent, low-mass disk over the lifetime of the solar system.

US Army Testing Multi-Mission Launcher Capable of Firing Multiple Missile Types

The US Army announced that it fired a Stinger missile from its self-built Multi-Mission Launcher on Wednesday at Eglin Air Force Base, Florida.

The missile test was part of a demonstration of the service’s new ground-based Indirect Fire Protection Capability Increment 2-Intercept (IFPC Inc 2-I) system to defeat unmanned aircraft systems, cruise missiles, rockets, artillery and mortars.

IFPC Inc 2-I will also use the Sentinel radar and the Integrated Air and Missile Defense Battle Command System (IBCS) for its command and control which will reach initial operational capability in fiscal 2019.

Stingers were developed as a man-portable air defense infrared homing surface-to-air missile, but has been “adapted to fire from a wide variety of ground vehicles,” the Army said in a statement released Thursday.

The MML is also able to fire Raytheon's AIM-9X Sidewinder missiles and Lockheed Martin's Longbow Hellfire missiles.

Other types of missiles will be tested at White Sands Missile Range, New Mexico, as part of an IFPC Inc 2-I engineering demonstration “in the coming weeks,” the Army said.

There are two prototypes of the MML which represent the first development of a major program by the government industrial base in more than 30 years, according to the statement.

link.

Stealth Saga #38

RQ-170:

Air and Space has a profile of the RQ-170.

UCLASS:

Despite doing a tanker drone first, the US Navy has stated it still wants a UCLASS drone.

The GAO reported on the progress on UCLASS.

ATD-X/X-2:

Here's a high resolution photo of the X-2. 

F-3:

Japan has reached out to Boeing and Lockheed for help in building its 5th generation fighter.  The Russians are calling the F-3 a sixth generation fighter.  That remains to be seen.

J-20:

PAK-FA:

The Indian variant of the PAK-FA, the FGFA, may end up armed with the hypersonic Brahmos missile.

B-21:

WiB argues the B-21 needs to become more open for it to survive the funding battles coming up.  Its not to say it should be a 'white' program, but less grey.  Unforunately, while they have the right idea, they use the disastrous Navy A-12 program as the basis of their argument.  The A-12 program was not canceled due to a funding fight with the F-22 though.  It was cancelled because it was run atrociously.


F-35:

The USS America has joined the fleet after having its deck strengthened for flying the F-35.

The US Marines will be standing up a second F-35B squadron in June.

The first USMC F-35B squadron will deploy on time to Japan.

The F-35A IOC may be delayed due to the software fixes.  And cyber vulnerabilities.

The total costs of F-35 acquisition has dropped $13 billion.

However, the last F-35 will fly until 2070 now.  That will increase the total life time costs of the program.  I also have a hard time believing the F-35 will remain in the inventory until I am 96.  There are going to be some major tech changes that will obsolete the F-35 by the 2050s at the latest.

The head of the F-35 program and the GAO are at odds.

The F-35 is going on a global publicity tour to wins hearts and minds at least of the legislatures backing the project.

WiB grouses at the expense of F-35 upgrades.

General:

A Chinese businessman has plead guilty to spying on the F-22 and F-35 programs.

The US Air Force is being criticized for still believing it can have a 100% stealth air fleet.

Does Climate Change Threaten the Primates?

This is the battle that nobody wins. According to a new study, climate change will adversely affect every single primate species on Earth. That’s every ape, monkey, gibbon, lemur and loris, no matter how super or strong they might be.

The study, published in the International Journal of Primatology, reveals that primate habitats will, on average, feel the pinch of a warming world 10 percent more severely than non-primate habitats. Not only will temperatures change, so will rainfall, with some species experiencing 7.5 percent more or less precipitation per degree C of global warming.

This is troubling news for the world’s primates, as many species rely on narrow habitats or have extremely specialized diets. Some primates only eat one or two things, so their food and habitats are particularly sensitive to disruption. Many primates are already endangered by habitat loss, hunting, or the illegal pet trade, so this additional threat could push several species over the brink.

link.

Evidence for an Aptian Cretaceous Carbon Perturbation in China

Lacustrine sedimentary record of early Aptian carbon cycle perturbation in western Liaoning, China

Authors:

Zhang et al

Abstract:

The early Aptian abrupt carbon isotope excursion in marine carbonate and sedimentary organic matter reflects a major perturbation in the global carbon cycle. However, until now almost all the evidences of this event came from marine deposits. Here we present organic-carbon isotope (δ13Corg) data from the non-marine Jehol Group in western Liaoning, China. The lacustrine δ13Corg curve is marked by a relative long-lasting δ13Corg minimum followed by two stages of positive δ13Corg excursions that are well correlated with contemporaneous marine records. The carbon isotope correlation shows that the lacustrine strata of the Jehol Group were deposited at the same time of the early Aptian Oceanic Anoxic Event (OAE1a). The relative long-lasting δ13Corg minimum supports the hypothesis that volcanic CO2 emission may have played the main role in triggering the negative δ13C excursion and global warming at the onset of this event. In addition, the onset of δ13Corg minimum is concomitant with the radiation of the Jehol Biota, implying that the evolutionary radiation of the Jehol Biota may have been closely related with the increase in atmospheric CO2 and temperature.

Purgatorius pinecreeensis: A New Omnivorous Species of Purgatoriid Plesiadapiform Primate From Paleocene Paleogene Saskatchewan, Canada

A new species of the basal plesiadapiform Purgatorius (Mammalia, Primates) from the early Paleocene Ravenscrag Formation, Cypress Hills, southwest Saskatchewan, Canada: further taxonomic and dietary diversity in the earliest primates

Authors:

Scott et al

Abstract:

The fossil record of the earliest primates, purgatoriid plesiadapiforms, has become increasingly well documented during the past two decades, but their dietary preferences remain poorly understood. While the available evidence, which consists mostly of isolated teeth and incomplete jaws with teeth, suggests that purgatoriids were insectivorous to omnivorous, we describe here a new species of Purgatorius, Purgatorius pinecreeensis sp. nov., that extends the range of purgatoriid dental disparity toward greater omnivory than had been known before. Purgatorius pinecreeensis sp. nov., from the early Paleocene (Puercan) Ravenscrag Formation of southwestern Saskatchewan, differs from other species of Purgatorius in having slightly lower crowned teeth with a lower trigonid relative to talonid, blunter and more swollen major cusps, more transverse lower molar paracristids, and m3 with a more robustly developed posterior lobe. Taken together, these specializations enhanced the capacity for crushing and grinding at the expense of orthal shear, and represent the first instance of a modest degree of bunodonty in the family. The discovery of P. pinecreeensis sp. nov., along with other recently reported basal plesiadapiforms from the Puercan and Torrejonian of the northern Western Interior, lends additional support to the notion of a significant primate radiation soon after the Cretaceous–Paleogene extinction event.

How Much can we Trust Zircons? Not Much for Archean South Africa

How far can we trust provenance and crustal evolution information from detrital zircons? A south African case study

Authors:

Andersen et al

Abstract:

U–Pb and Lu-Hf data are routinely used to trace detrital zircon in clastic sediments to their original source in crystalline bedrock (the protosource), to map out paths of sediment transport, and characterize large-scale processes of crustal evolution. For such data to have a provenance significance, a simple transport route from the protosource in which the zircon formed to its final site of deposition is needed. However, detrital zircon data from Phanerozoic sedimentary cover sequences in South Africa suggest that this “source to sink” relationship has been obscured by repeated events of sedimentary recycling. Phanerozoic sandstones (Cape Supergroup, Karoo Supergroup, Natal Group, Msikaba Formation) and unconsolidated, Cenozoic sands in South Africa share major detrital zircon fractions of late Mesoproterozoic (940–1120 Ma, εHf ≈ 0 to + 15) and Neoproterozoic age (470–720 Ma, εHf ≈ − 10 to + 8). A Permian age fraction (240–280 Ma, εHf ≈ − 8 to + 5) is prominent in sandstones from the upper part of the Karoo Supergroup. All of these sequences are dominated by material derived by recycling of older sedimentary rocks, and only the youngest, late Palaeozoic fraction has a clear provenance significance (Gondwanide orogen). The virtual absence of Archaean zircon is a striking feature in nearly all suites of detrital zircon studied in the region. This indicates that significant events in the crustal evolution history of southern African and western Gondwana are not represented in the detrital zircon record. South Africa provides us with a record of recycling of cover sequences throughout the Phanerozoic, and probably back into the Neoproterozoic, in which the “sink” of one sedimentary cycle will act as the “source” in subsequent cycles. In such a setting, detrital zircon may give information on sedimentary processes rather than on provenance.

Measuring the Speed of Sound in Titan's Seas Might Reveal Their Composition

How speed of sound measurements could bring constraints on the composition of Titan's seas

Author:

Cordier

Abstract:

The hydrocarbons seas of Titan, discovered by Cassini/Huygens mission are among the most mysterious and interesting features of this moon. In the future, a possible dedicated planetary probe, will certainly measure the speed of sound in this cryogenic liquid, as it was planned in the case of a Huygens landing into a sea. Previous theoretical studies of such acoustic measurements were based on rather simple models, leading in some cases to unphysical situations. Employed in a vast body of chemical engineering works, the state of the art PC-SAFT model has been recently introduced in studies aimed at Titan. Here, I revisit the issue of the speed of sound in Titan's liquids, in the light of this theory. I describe, in detail, the derivation of the speed of sound from the chosen equation of state and the potential limitations of the approach. To make estimations of the composition of a ternary liquid mixture N2:CH4:C2H6 from speed of sound measurements an original inversion algorithm is proposed. It is shown that 50 measures between 90 K and 100 K are enough to ensure an accuracy of the derived compositions better than 10%. The influence of the possible presence of propane is also investigated.

Argon isotopes as tracers for martian atmospheric loss

Argon isotopes as tracers for martian atmospheric loss

Authors:

Slipski et al

Abstract:

Recent measurements of the present-day Ar abundance and isotopic ratios in the martian atmosphere by the SAM instrument suite onboard the Curiosity rover can be used to constrain the atmospheric and volatile evolution. We have examined the role of volcanic outgassing, escape to space via sputtering, crustal erosion, impact delivery, and impact erosion in reproducing the Ar isotope ratios from an initial state 4.4 billion years ago. To investigate the effects of each of these processes, their timing, and their intensity we have modeled exchanges of Ar isotopes between various reservoirs (mantle, crust, atmosphere, etc.) throughout Mars’ history. Furthermore, we use present-day atmospheric measurements to determine the parameter space consistent with observations. We find that significant loss to space (at least 48% of atmospheric 36Ar) is required to match the observed 36Ar/38Ar ratio. Our estimates of volcanic outgassing do not supply sufficient 40Ar to the atmosphere to match observations, so in our model at least 31% of 40Ar produced in the crust must have also been released to the atmosphere. Of the total 40Ar introduced into the atmosphere about 25% must have been lost to space. By adding the present-day isotopic abundances with our results of total integrated Ar loss we find a “restored” value of atmospheric 40Ar/36Ar, which represents what that ratio would be if the total integrated Ar loss had remained in the atmosphere. We determine the restored value to be ∼900–1500. This is below the present martian atmospheric value (1900 ± 300), but 3–5 times greater than the terrestrial value.

Frozen Nitrogen Lake, Channels Spotted on Pluto

NASA's New Horizons spacecraft spied several features on Pluto that offer evidence of a time millions or billions of years ago when – thanks to much higher pressure in Pluto's atmosphere and warmer conditions on the surface – liquids might have flowed across and pooled on the surface of the distant world.

"In addition to this possible former lake, we also see evidence of channels that may also have carried liquids in Pluto's past," said Alan Stern, Southwest Research Institute, Boulder, Colorado—principal investigator of New Horizons and lead author of the scientific paper.

This feature appears to be a frozen, former lake of liquid nitrogen, located in a mountain range just north of Pluto's informally named Sputnik Planum. Captured by the New Horizons' Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Pluto on July 14, 2015, the image shows details as small as about 430 feet (130 meters). At its widest point the possible lake appears to be about 20 miles (30 kilometers) across.

link.

Russian Navy Upgrading Akula Class Attack Subs to use Kalibr (Sizzler) Antiship missiles

The upgrade of Russia's Project 971 Bars ('Akula')-class nuclear-powered attack submarines will arm them with Kalibr 3M-54 (SS-N-27A 'Sizzler') anti-ship missiles, Viktor Kochemazov, chief of the Russian Navy Training Department, told the RSN radio channel on 21 March. "Now, the upgrade of the Project 971 submarines provides for equipping them with the Kalibr system," he said.

The weapon "proved itself" during trials, according to Kochemazov. "Its use by the Rostov-on-Don diesel-electric submarine showed that the system is facing bright vistas in terms of further development," he said.

link.

US Navy Planning Network of Robo Subs, Drones to Work with Future Attack Subs

Submarines today, and even more so in the future, will not only deliver weapons but will also carry a family of unmanned underwater and aerial vehicles to help extend their area of influence. Richard said the Navy has bought about 150 3-inch unmanned aerial vehicles (UAVs) and about a dozen 21-inch UAVs that are fully integrated with the submarine and send information back. The submarine community also has 16 21-inch Littoral Battlespace Sensing Autonomous Underwater Vehicles coming into the fleet for additional intelligence-gathering underwater.

In the future, though, Richard said there will be more UUVs, but “they won’t always come by submarine, they may come by a number of mechanisms – you may launch them from a surface ship, they may be launched from the pier. It’s just a capability, a node in an undersea constellation that will include the seabed, fixed distributed systems. Not all UUVs are going to look like little submarines, there’s a bunch of different ways to put this effect in there.”

This idea plays into Richard’s view of the undersea domain – operations shouldn’t be platform-centric but rather domain-centric. In a graphic of future underwater operations, Richard said “the submarine’s not in the middle of the picture. That’s intentional to show that it is just part of a larger system that we’re putting out there.”

link.

report to congress on UUVs.

T-90 Tank Appears to Have Survived TOW Missile Hit

For all the videos coming out of the Syrian civil war, a one minute, 31-second clip of a U.S.-made TOW missile slamming into a T-90 tank got more attention than most. In the video uploaded in February, Russia’s most advanced operational battle tank met one of the United States’ main tank killers on the battlefield.

The T-90 was Russian made, but likely crewed by Syrian troops. The missile was supplied by the United States — most likely via Saudi Arabia or the CIA — to the Hawks Mountain Brigade fighting near Aleppo.

For the participants, the whole experience might have been terrifiying. For most of the rest of the world, it was a chance to see what happens when state-of-the-art hardware from two major world powers violently collide in the Middle East.

The only good news is that nobody appeared to get killed. What happened to the tank … well, no one who watched the video was exactly sure.

We saw the wire-guided missile bob toward the T-90, which was parked on a crest between two low-slung buildings. Then the missile hit the tank’s turret with a tremendous flash which sent up a cloud of smoke. One of the crew members bailed and the video ended.

There was no fire and the tank didn’t “brew up,” meaning the fuel tank didn’t ignite and burn the crew to death. (The Syrian army has lost thousands of tanks since the war began in 2011.) This one, it seemed, survived.

A recent photograph circulated on Russian military forums shows what the tank looked like after impact. Sure enough, the T-90’s Kontakt-5 reactive armor appeared to save it. Reactive armor explodes outwards and stops incoming missiles from penetrating into the tank and killing the crew.

link.

In 1200 BC a Massive Battle Over a Bridge Took Place in the Tollense Valley

About 3200 years ago, two armies clashed at a river crossing near the Baltic Sea. The confrontation can’t be found in any history books—the written word didn’t become common in these parts for another 2000 years—but this was no skirmish between local clans. Thousands of warriors came together in a brutal struggle, perhaps fought on a single day, using weapons crafted from wood, flint, and bronze, a metal that was then the height of military technology.

Struggling to find solid footing on the banks of the Tollense River, a narrow ribbon of water that flows through the marshes of northern Germany toward the Baltic Sea, the armies fought hand-to-hand, maiming and killing with war clubs, spears, swords, and knives. Bronze- and flint-tipped arrows were loosed at close range, piercing skulls and lodging deep into the bones of young men. Horses belonging to high-ranking warriors crumpled into the muck, fatally speared. Not everyone stood their ground in the melee: Some warriors broke and ran, and were struck down from behind.

link.

Potentially NO Aptian and Albian Cretaceous Atmospheric CO2 changes during oceanic anoxic events

Aptian and Albian atmospheric CO2 changes during oceanic anoxic events: Evidence from fossil Ginkgo cuticles in Jilin Province, Northeast China

Authors:

Sun et al

Abstract:

The Early Cretaceous was a time with super-greenhouse conditions and episodic global oceanic anoxic events. However, relative timing of atmospheric CO2 emissions and oceanic anoxic events, and their causal relationships remain matters of debate. Using the stomatal index approach, well-preserved fossil cuticles of Ginkgo from the Lower Cretaceous Changcai Formation, eastern Jilin, and from the Lower Cretaceous Yingcheng Formation, central Jilin, Northeast China, were investigated to reconstruct atmospheric CO2 concentrations during the Aptian and earliest Albian (Early Cretaceous). The results indicate that the CO2 concentrations reached 1098–1142 ppmv (Carboniferous standardization) or 970–1305 ppmv (regression function) during the Aptian and earliest Albian. Our estimates of palaeoatmospheric CO2 concentrations during the earliest Albian (OAE 1b) are slightly higher than the data between the early Aptian Selli (OAE 1a) and the middle Aptian Fallot OAEs; this may indicate the absence of any great emissions of CO2 during the latest Aptian and earliest Albian.

Montirictus kuwajimaensis: a new Tritylodontid Mammaliamorph From Barremian/Aptian Cretaceous Japan

A new Early Cretaceous tritylodontid (Synapsida, Cynodontia, Mammaliamorpha) from the Kuwajima Formation (Tetori Group) of central Japan

Authors:

Matsuoka et al

Abstract:

We describe tritylodontid remains from the Lower Cretaceous Kuwajima Formation (Tetori Group) in central Japan as representing a new genus, Montirictus kuwajimaensis, gen. et sp. nov. Montirictus is a medium-sized tritylodontid genus characterized by upper cheek teeth having the cusp formula 2-2-2 with subequal cusps, buccal and lingual cusps retaining a crescentic shape with both buccal and lingual ridges anteriorly, and ‘V’-shaped buccolingual cross-sections of two anteroposterior grooves between the three cusp rows. Tentative dating of the Kuwajima Formation to the Barremian–Aptian makes it the stratigraphically youngest representative of a long-lived, globally distributed and abundant mammaliamorph lineage and extends the known geographic range of tritylodontids.

Where did all the Impactors Come From During the PaleoArchean?

Spherule layers, crater scaling laws, and the population of ancient terrestrial impactors

Authors:

Johnson et al

Abstract:

Ancient layers of impact spherules provide a record of Earth's early bombardment history. Here, we compare different bombardment histories to the spherule layer record and show that 3.2–3.5 Ga the flux of large impactors (10–100 km in diameter) was likely 20–40 times higher than today. The E-belt model of early Solar System dynamics suggests that an increased impactor flux during the Archean is the result of the destabilization of an inward extension of the main asteroid belt (Bottke et al., 2012). Here, we find that the nominal flux predicted by the E-belt model is 7–19 times too low to explain the spherule layer record. Moreover, rather than making most lunar basins younger than 4.1 Gyr old, the nominal E-belt model, coupled with a corrected crater diameter scaling law, only produces two lunar basins larger than 300 km in diameter. We also show that the spherule layer record when coupled with the lunar cratering record and careful consideration of crater scaling laws can constrain the size distribution of ancient terrestrial impactors. The preferred population is main-belt-like up to ∼50 km in diameter transitioning to a steep distribution going to larger sizes.

The Tallest Mountains on Titan Named

In a nod to extraterrestrial mountaineers of the future, scientists working on NASA's Cassini mission have identified the highest point on Saturn's largest moon, Titan.

Titan's tallest peak is 10,948 feet (3,337 meters) high and is found within a trio of mountainous ridges called the Mithrim Montes. The researchers found that all of Titan's highest peaks are about 10,000 feet (3,000 meters) in elevation. The study used images and other data from Cassini's radar instrument, which can peer through the obscuring smog of Titan's atmosphere to reveal the surface in detail.

"It's not only the highest point we've found so far on Titan, but we think it's the highest point we're likely to find," said Stephen Wall, deputy lead of the Cassini radar team at NASA's Jet Propulsion Laboratory in Pasadena, California.

The results, which use data collected by Cassini's radar instrument, are being presented today at the 47th annual Lunar and Planetary Science Conference at The Woodlands, Texas.

Most of Titan's tallest mountains appear to be close to the equator. The researchers identified other peaks of similar height within the Mithrim Montes, as well as in the rugged region known as Xanadu, and in collections of more isolated peaks called "ridge belts" located near the landing site of ESA's Huygens probe.

link.

Modeling Titan's Upper Atmosphere

Examining the exobase approximation: DSMC models of Titan's upper atmosphere

Authors:

Tucker et al

Abstract:

Chamberlain ([1963] Planet. Space Sci., 11, 901–960) described the use of the exobase layer to determine escape from planetary atmospheres, below which it is assumed that molecular collisions maintain thermal equilibrium and above which collisions are deemed negligible. De La Haye et al. ([2007] Icarus., 191, 236–250) used this approximation to extract the energy deposition and non-thermal escape rates for Titan's atmosphere by fitting the Cassini Ion Neutral Mass Spectrometer (INMS) density data. De La Haye et al. assumed the gas distributions were composed of an enhanced population of super-thermal molecules (E >> kT) that could be described by a kappa energy distribution function (EDF), and they fit the data using the Liouville theorem. Here we fitted the data again, but we used the conventional form of the kappa EDF. The extracted kappa EDFs were then used with the Direct Simulation Monte Carlo (DSMC) technique (Bird [1994] Molecular Gas Dynamics and the Direct Simulation of Gas Flows) to evaluate the effect of collisions on the exospheric profiles. The INMS density data can be fit reasonably well with thermal and various non-thermal EDFs. However, the extracted energy deposition and escape rates are shown to depend significantly on the assumed exobase altitude, and the usefulness of such fits without directly modeling the collisions is unclear. Our DSMC results indicate that the kappa EDFs used in the Chamberlain approximation can lead to errors in determining the atmospheric temperature profiles and escape rates. Gas kinetic simulations are needed to accurately model measured exospheric density profiles, and to determine the altitude ranges where the Liouville method might be applicable.

The Paleoclimate and Enviroment of Early Cretaceous Sichuan Basin, China

Lower Cretaceous paleosols and paleoclimate in Sichuan Basin, China

Authors:

Li et al

Abstract:

Abundant Lower Cretaceous (Berriasian–Hauterivian) paleosols have been recognized in the Sichuan Basin, along with the preserved pedogenetic features, e.g., soil horizons, soil structure, root traces and pedogenic nodules. Chemical, geochemical and mineralogical analyses were used to examine the paleosols. These paleosols were classified as Entisols, Inceptisols, Aridisols and Alfisols in terms of the modern soil taxonomic system. Early Cretaceous paleoprecipitation and paleotemperature in the Sichuan Basin were estimated from the degree of chemical weathering for non-calcareous paleosols, and from the depth to the calcic horizon and stable oxygen isotopic composition of pedogenic carbonates in calcareous paleosols, respectively. A temperate semi-arid climate generally prevailed in the Sichuan Basin as a part of the South China Block (SCB) and was controlled by subtropical high-pressure and a rain-shadow effect because the humid air masses from the Paleo-Pacific were impeded by the highlands of the South China Block. Further, several intervals of sub-humid paleoclimate occurred due to strengthened monsoonal circulation in the Early Cretaceous. Using the paleosol barometer, the paleoatmospheric CO2 levels of the Early Cretaceous are estimated to range from ∼120 to ∼520 ppmv, with a mean of 305 ppmv. Regional temperature is generally coupled with atmospheric CO2 concentration and is roughly consistent with the sea level fluctuation.

A Chalicothere Found in Mioecene Neogene Japan

Femur of Schizotheriinae (Perissodactyla, Chalicotheriidae) from the Lower Miocene Hiramaki Formation of the Mizunami Group in Gifu Prefecture, central Japan

Sadly, no abstract available.

Bdelloid rotifers Exchange DNA Like Bacteria do, a First for Metazoans (animals)

Bdelloid rotifers were believed to have persisted and diversified in the absence of sex. Two papers now show they exchange genes with each other, via horizontal gene transfers as known in bacteria and/or via other forms of non-canonical sex.

link.

The "Magic Islands" of Titan's Ligeia Mare are Probably Large Waves

Titan’s “Magic Islands”: Transient features in a hydrocarbon sea

Authors:

Hofgartner et al

Abstract:

The region of Titan’s hydrocarbon sea, Ligeia Mare, where transient bright features were previously discovered, was anomalously bright in the first of two more recent Cassini RADAR observations but not the second. Another transient bright feature in a different region of Ligeia Mare was also discovered in the first of the new observations. Here we present all the high-resolution observations of the regions containing these transient features and the quantitative constraints that we derived from them. We argue that these features are unlikely to be SAR image artifacts or permanent geophysical structures and thus their appearance is the result of ephemeral phenomena on Titan. We find that the transient features are more consistent with floating and/or suspended solids, bubbles, and waves than tides, sea level change, or seafloor change and based on the frequency of these phenomena in terrestrial settings, we consider waves to be the most probable hypothesis. These transient features are the first instance of active processes in Titan’s lakes and seas to be confirmed by multiple detections and demonstrate that Titan’s seas are not stagnant but rather dynamic environments.

Fluvial erosion as a mechanism for crater modification on Titan

Fluvial erosion as a mechanism for crater modification on Titan

Authors:

Neish et al

Abstract:

There are few identifiable impact craters on Titan, especially in the polar regions. One explanation for this observation is that the craters are being destroyed through fluvial processes, such as weathering, mass wasting, fluvial incision and deposition. In this work, we use a landscape evolution model to determine whether or not this is a viable mechanism for crater destruction on Titan. We find that fluvial degradation can modify craters to the point where they would be unrecognizable by an orbiting spacecraft such as Cassini, given enough time and a large enough erosion rate. A difference in the erosion rate between the equator and the poles of a factor of a few could explain the latitudinal variation in Titan’s crater population. Fluvial erosion also removes central peaks and fills in central pits, possibly explaining their infrequent occurrence in Titan craters. Although many craters on Titan appear to be modified by aeolian infilling, fluvial modification is necessary to explain the observed impact crater morphologies. Thus, it is an important secondary modification process even in Titan’s drier equatorial regions.

A SETI Institute Lecture on the Outer Solar System

Converging on Cryptocurrencies #5

AltCoins:

GridCoin is an attempt to incentivize doing BOINC related science computing. This is something I discussed with friends at LBNL a couple years ago. The timing is...amusing.

The Bank of England has paid for the development of RSCoin, a centrally controlled cryptocurrency.  It matches, really well actually, what I predicted for a 'cryptodollar' would be from the US.

Bitcoin:

There was a big mix up about whether or not Microsoft would be accepting bitcoin.

Quickbit, a bitcoin trading platform, had a cyberattack and will be down for an extended period. No funds were supposedly lost though.

Crime:

BitcoinWisdom Ads Remover is a Chrome extension implicated in stealing bitcoins from transactions.

Law enforcement actually really likes bitcoin because it allows for tracking the transactions very clearly due to its public ledger (blockchain).

Regulation:

Bitcoin issuers in Russia face seven years in prison.

Misc:

Should we fear a cashless world?

Greatest Megafauna Mammal Extinctions in Europe Began 3,000 Years Ago

Millennial-scale faunal record reveals differential resilience of European large mammals to human impacts across the Holocene

Authors:

Crees et al

Abstract:

The use of short-term indicators for understanding patterns and processes of biodiversity loss can mask longer-term faunal responses to human pressures. We use an extensive database of approximately 18 700 mammalian zooarchaeological records for the last 11 700 years across Europe to reconstruct spatio-temporal dynamics of Holocene range change for 15 large-bodied mammal species. European mammals experienced protracted, non-congruent range losses, with significant declines starting in some species approximately 3000 years ago and continuing to the present, and with the timing, duration and magnitude of declines varying individually between species. Some European mammals became globally extinct during the Holocene, whereas others experienced limited or no significant range change. These findings demonstrate the relatively early onset of prehistoric human impacts on postglacial biodiversity, and mirror species-specific patterns of mammalian extinction during the Late Pleistocene. Herbivores experienced significantly greater declines than carnivores, revealing an important historical extinction filter that informs our understanding of relative resilience and vulnerability to human pressures for different taxa. We highlight the importance of large-scale, long-term datasets for understanding complex protracted extinction processes, although the dynamic pattern of progressive faunal depletion of European mammal assemblages across the Holocene challenges easy identification of ‘static’ past baselines to inform current-day environmental management and restoration.

Estimating Carbon dioxide Levels From the Early Cretaceous

Atmospheric palaeo-CO2 estimates based on the carbon isotope and stomatal data of Cheirolepidiaceae from the Lower Cretaceous of the Jiuquan Basin, Gansu Province

Authors:

Du et al

Abstract:

The stable carbon isotope compositions and the stomatal parameters (stomatal density and stomatal index) of four Cheirolepidiaceae species, Brachyphyllum ningxiaensis, Brachyphyllum obtusum, Pseudofrenelopsis dalatzensis and Pseudofrenelopsis gansuensis, were analyzed to recover the late Early Cretaceous atmospheric CO2 levels. The fossil plants were collected from 5 consecutive sedimentary members of the uppermost Zhonggou Formation. Based on the stomatal data, the estimated palaeo-atmospheric CO2 concentrations in the Jiuquan Basin during the late Early Cretaceous were 1060–882 ppmv based on the carboniferous standardization and were 641–531 ppmv based on the recent standardization; the pCO2 values present at first a decreasing and then an increasing trend within the sedimentary time of the five members. The δ13Cp values based on the 21 Brachyphyllum specimens showed a large variation, which ranged from −20.98‰ to −25.69‰, with an average of −24.2‰. The values also identified a C3 photosynthetic pathway for the Brachyphyllum specimens. The predicted δ13Ca values varied from −2.1‰ to −6.38‰, with an average of −5.03‰. These two proxies were irregular within the different members; therefore, the correlation with the change in atmospheric CO2 concentrations was not significant. Moreover, a water-stressed environment was proposed based on the δ13C values of the present fossil plants, a proposal that was also supported by the previous palaeobotanical, palynological and stratigraphical evidence. In the present study, an inconsistent relationship between the stable carbon isotope and the stomata values was apparent, which most likely indicated that the stomata numbers of the plant were more sensitive to the variation in the concentration of the atmospheric CO2, whereas the δ13C values were sensitive to the moisture conditions.

A Juvenile Barosaurs (sauropod) From Jurassic Utah also had an Avian-like Airsac Respiratory System

A juvenile sauropod dinosaur from the Late Jurassic of Utah, U.S.A., presents further evidence of an avian style air-sac system

Authors:

Melstrom et al

Abstract:

Well-preserved, articulated juvenile sauropod dinosaur material is very rare, hindering attempts to understand ontogenetic changes within the clade. Here, we describe an exceptionally preserved partial skeleton of a Barosaurus from the Morrison Formation of Dinosaur National Monument, Utah, U.S.A., that is only about one-third adult size. This small size and the lack of fusion of neurocentral and costovertebral sutures indicate that the individual is a juvenile. Apomorphy-based taxonomic identification of the specimen combined with the excellent preservation of its vertebral column allows documentation of both serial and ontogenetic morphological changes in Barosaurus. Each vertebra underwent substantial morphological change in the relative height of the neural spine and location of the zygapophyseal and diapophyseal articular facets during ontogeny but not in the degree of bifurcation of the neural spines. Pneumaticity in the dorsal vertebrae varies serially: large pneumatic fossae punctuate the centra of dorsal vertebrae 1–4 and 8–9, whereas these spaces are occupied by shallow depressions in dorsal vertebrae 5–7. This represents the first known caudal dorsal pneumatic hiatus in a sauropod dinosaur, which suggests that separate air sacs pneumatized the anterior and posterior regions of the dorsal vertebral column, congruent with the pattern observed in non-avian and avian theropod dinosaurs and the presence of an avian-style lung in sauropods.

A new Burgess Shale-type Lagertatte From the Ediacaran NeoProterozoic Mongolia

A new Burgess Shale-type deposit from the Ediacaran of western Mongolia

Authors:

Dornbos et al

Abstract:

Preservation of soft-bodied organisms is exceedingly rare in the fossil record. One way that such fossils are preserved is as carbonaceous compressions in fined-grained marine sedimentary rocks. These deposits of exceptional preservation are known as Burgess Shale-type (BST) deposits. During the Cambrian Period, BST deposits are more common and provide a crucial view of early animal evolution. The earliest definitive fossil evidence for macroscopic animal-grade organisms is found in the preceding Ediacaran Period. BST deposits from the Ediacaran are rarer and lack conclusive evidence for animals. Here we report the discovery of a new Ediacaran BST deposit with exceptional preservation of non-mineralizing macro-organisms in thinly bedded black shale from Zavkhan Province, western Mongolia. This fossil assemblage, here named the Zuun-Arts biota, currently consists of two new species of probable macroscopic multicellular benthic algae. One species, Chinggiskhaania bifurcata n. gen., n. sp., dominates the biota. The other species, Zuunartsphyton delicatum n. gen., n. sp., is known from three specimens. SEM-EDS analysis shows that the fossils are composed of aluminosilicate clay minerals and some carbon, a composition comparable to fossils from the Cambrian Burgess Shale biota. This discovery opens a new window through which to view late Precambrian life.

pop sci link.

The fate of ethane in Titan’s hydrocarbon lakes and seas

The fate of ethane in Titan’s hydrocarbon lakes and seas

Authors:

Mousis et al

Abstract:

Ethane is expected to be the dominant photochemical product on Titan’s surface and, in the absence of a process that sequesters it from exposed surface reservoirs, a major constituent of its lakes and seas. Absorption of Cassini’s 2.2 cm radar by Ligeia Mare however suggests that this north polar sea is dominated by methane. In order to explain this apparent ethane deficiency, we explore the possibility that Ligeia Mare is the visible part of an alkanofer that interacted with an underlying clathrate layer and investigate the influence of this interaction on an assumed initial ethane–methane mixture in the liquid phase. We find that progressive liquid entrapment in clathrate allows the surface liquid reservoir to become methane-dominated for any initial ethane mole fraction below 0.75. If interactions between alkanofers and clathrates are common on Titan, this should lead to the emergence of many methane-dominated seas or lakes.

The physical properties of Titan’s empty lake basins

Constraining the physical properties of Titan’s empty lake basins using nadir and off-nadir Cassini RADAR backscatter

Authors:

Michaelides et al

Abstract:

We use repeat synthetic aperture radar (SAR) observations and complementary altimetry passes acquired by the Cassini spacecraft to study the scattering properties of Titan’s empty lake basins. The best-fit coefficients from fitting SAR data to a quasi-specular plus diffuse backscatter model suggest that the bright basin floors have a higher dielectric constant, but similar facet-scale rms surface facet slopes, to surrounding terrain. Waveform analysis of altimetry returns reveals that nadir backscatter returns from basin floors are greater than nadir backscatter returns from basin surroundings and have narrower pulse widths. This suggests that floor deposits are structurally distinct from their surroundings, consistent with the interpretation that some of these basins may be filled with evaporitic and/or sedimentary deposits. Basin floor deposits also express a larger diffuse component to their backscatter, which is likely due to variations in subsurface structure or an increase in roughness at the wavelength scale (Hayes, A.G. et al. [2008]. Geophys. Res. Lett. 35, 9). We generate a high-resolution altimetry radargram of the T30 altimetry pass over an empty lake basin, with which we place geometric constraints on the basin’s slopes, rim heights, and depth. Finally, the importance of these backscatter observations and geometric measurements for basin formation mechanisms is briefly discussed.

Raytheon's KTech Contracted to Convert 2 Cruise Missiles Into EMP Weapons for Demo

Raytheon’s acquisition of directed energy firm Ktech in 2011 is paying dividends following the US Defense Department’s award of a $4.8 million contract to repackage two air-launched cruise missiles as high-power microwave weapons.

Ktech produced the pulsing electronics kit that Boeing proved could knock out banks of computers in an October 2012 flight demonstration, overseen by the US Air Force Research Laboratory's (AFRL).

The award to Raytheon is the first significant movement on the so-called Counter-electronics High-power microwave Advanced Missile Project (CHAMP) since that 2012 demonstration. The announcement is a blow to Boeing, which no longer leads the effort.

link.

USS Zumwalt Finishes Builder's Trials

Next generation guided missile destroyer Zumwalt (DDG-1000) is back at General Dynamics Bath Iron Works shipyard after four days of successful builder’s trails, according to the service.

The service will now prepare for next month’s acceptance trials ahead of delivery of the ship to the Navy. The ship arrived Thursday afternoon to the Maine yard, sources who saw the ship return to its pier at BIW told USNI News.

During the four days of trials, “representatives from BIW, PCU Zumwalt, the Navy’s Program Office, SUPSHIP Bath and various technical subject matter experts, including Raytheon personnel, tested several ship systems including key propulsion and auxiliary systems as well as boat operations,” read a Friday statement provided to USNI News by the service.

link.

The Coming Cyberwar #6

Cyber Security:

Was there a big breakthrough in cyber security?

Does NASA also have a cybersecurity breakthrough called Gryphon-X?  And why is it at NASA?

The Internet of Things is a security nightmare.

Cyberwarfare:

Cybercommand is looking to work closer with industry.

The wrap up of the series about how the US Navy will fight a war with cyberwarfare being a component.

Cyber attacks can even have effect at the tactical level in the US Army.

Three have been charged for having ties to the Syrian Electronic Army.

Hacking:

In a real cyberwar, unlike in a physical war, hospitals are likely to be some of the major targets.  For hackers, they already are.  Hospitals are being targeted by ransomware.

healthcare.gov has reported 316 cybersecurity incidents.

The US has indicted 7 Iranians on hacking the dam and financial institutions.  A Senator is calling the New York dam hack a wake up call.

The FBI is warning car hacking is a very real threat.

Dozens of Russians banks were hacked.

A security researcher has disappeared while digging into a Bangladesh bank hack.

Some are saying not to panic over the new iphone hack.

There is a new malware targeting air gapped systems called 'USB Thief.'