Friday, September 30, 2016

NASA has confirmed “statistically significant evidence” from the Hubble Space Telescope indicating the presence of salty watery ejecta plumes from the Jovian moon Europa. The announcement lends further proof for the existence of a deep, saline ocean under Europa’s icy surface and creates new urgency and objectives for NASA’s upcoming Europa Clipper mission in the mid-2020s.

NASA's New Horizons spacecraft observed (15810) 1994 JR1, a 3:2 resonant Kupier Belt Object (KBO), using the LOng Range Reconnaissance Imager (LORRI) on November 2, 2015 from a distance of 1.85 AU, and again on April 7, 2016 from a distance of 0.71 AU. These were the first close observations of any KBO other than Pluto. Combining ground-based and Hubble Space Telecope (HST) observations at small phase angles and the LORRI observations at higher phase angles, we produced the first disk-integrated solar phase curve of a typical KBO from α=0.6-58∘. Observations at these geometries, attainable only from a spacecraft in the outer Solar System, constrain surface properties such as macroscopic roughness and the single particle phase function. 1994 JR1 has a rough surface with a 37±5∘ mean topographic slope angle and has a relatively rapid rotation period of 5.47±0.33 hours. 1994 JR1 is currently 2.7 AU from Pluto; our astrometric points enable high-precision orbit determination and integrations which show that it comes this close to Pluto every 2.4 million years (104 heliocentric orbits), causing Pluto to perturb 1994 JR1. During the November spacecraft observation, the KBO was simultaneously observed using HST in two colors, confirming its very red spectral slope. These observations have laid the groundwork for numerous potential future distant KBO observations in the New Horizons-Kuiper Belt Extended Mission.

The atmospheric circulation in Venus is well known to exhibit strong super-rotation. However, the atmospheric mechanisms responsible for the formation of this super-rotation are still not fully understood. In this work, we developed a new Venus general circulation model to study the most likely mechanisms driving the atmosphere to the current observed circulation. Our model includes a new radiative transfer, convection and suitably adapted boundary layer schemes and a dynamical core that takes into account the dependence of the heat capacity at constant pressure with temperature.

The new Venus model is able to simulate a super-rotation phenomenon in the cloud region quantitatively similar to the one observed. The mechanisms maintaining the strong winds in the cloud region were found in the model results to be a combination of zonal mean circulation, thermal tides and transient waves. In this process, the semi-diurnal tide excited in the upper clouds has a key contribution in transporting axial angular momentum mainly from the upper atmosphere towards the cloud region. The magnitude of the super-rotation in the cloud region is sensitive to various radiative parameters such as the amount of solar radiative energy absorbed by the surface, which controls the static stability near the surface. In this work, we also discuss the main difficulties in representing the flow below the cloud base in Venus atmospheric models.

Our new radiative scheme is more suitable for 3D Venus climate models than those used in previous work due to its easy adaptability to different atmospheric conditions. This flexibility of the model was crucial to explore the uncertainties in the lower atmospheric conditions and may also be used in the future to explore, for example, dynamical-radiative-microphysical feedbacks.

Today, SpaceX CEO Elon Musk unveiled the Mars vehicle — the spaceship his company plans to build to transport the first colonists to Mars. The spaceship is meant to launch from Earth on top of the booster and then travel the rest of the way on its own to the Red Planet.

Though not finalized, the first spaceship will probably be named “Heart of Gold,” a reference to the spacecraft in Douglas Adams’ Hitchhiker’s Guide to the Galaxy. It will have a diameter of 17 meters.

The plan is to send about 100 people per trip, though Musk wants to ultimately take 200 or more per flight to make the cost cheaper per person. The trip can take as little as 80 days or as many as 150 depending on the year and the technology. The hope is that the transport time will be only 30 days “in the more distant future.”

Yahoo was hacked and 500 million users data has been exposed. Phone companies whose users used Yahoo ought to be concerned. That Yahoo waited two years to report the attack is being called unacceptable. The party who hacked Yahoo is in dispute.

Russia is preparing to renew flight testing of a high-power flying laser designed to operate as an anti-satellite weapon, the Tass news agency reported. Mounted on a modified Ilyushin Il-76MD-90E transport plane the airborne laser laboratory aircraft flew for its first test mission in August 19, 1981. Two aircraft were modified and equipped for the tests that ceased following the collapse of the Soviet Union. In 2009 the project was revived as the A-60SE, mounting the original 1LK222 laser. This laser weapon will likely be used to dazzle adversary satellites or burning through sensitive optics and sensors using intensive enery laser bursts. With an effective range of 1,500 km (930 miles) such a laser can target reconnaissance satellites orbiting at low earth orbit (LEO). The effect on target range to temporarily disrupt to disabling adversary reconnaissance or missile warning satellites. Some sources claim the program also aims to develope a more powerful laser, that will be able to defeat aircraft and missiles.

The program discontinued in 2011 due to lack of funding but has apparently regained interest among Moscow’s strategists as it is considered as an asymmetrical response to looming space-based threats. Platforms suggested for the operational systems may be the original, refurbished A-60SE, newer Ilyushin-476 platforms, or the prospective strategic bomber PAK-DA.

The Russian laser weapon is not equivalent to the American anti-ballistic laser (ABL) developed and tested in the early 2000s. The United States developed a much more powerful chemical laser designated YAL-1. It was designed as an anti-missile proof of concept. YAL-1 demonstrated such capabilities in 2010, but the results were incolclusive and the project was scraped in 2011. According to some media sources the Russians could be considering a similar high power chemical laser for the ‘Sokol Eshelon’ (Falcon-Eshelon) program, developed by Voronezh-based Khimprom-Avtomatika corporation.

Assessing the onset and extent of Northern Hemisphere glaciation is required to understand Cenozoic climate change and its impact on topography. While the onset of accelerated Cenozoic erosion is generally associated with the Quaternary at mid-latitudes, some high-latitude passive margins may have undergone earlier glaciation starting at 38–30 Ma or even 45 Ma. Here we document a rapid phase of exhumation in the East Greenland margin between 68°N and 76°N starting at 30 ± 5 Ma. The timing is coincident with the dramatic worldwide fall of surface temperature at the Eocene-Oligocene transition. Our inference is based on apatite fission track and apatite helium data. We suggest that a transition from an Eocene fluvial to an Oligocene glacial-dominated landscape triggered a period of enhanced erosion. This study provides the first onshore potential evidence of the onset of continental ice in East Greenland margin at the Eocene-Oligocene transition (ca. 34 Ma), contemporaneously with the onset of Antarctica glaciation and erosion. Our interpretation is consistent with that based on the oldest ice-rafted debris found in the sedimentary records offshore East Greenland and implies that East Greenland exhibits the oldest onshore record of Cenozoic glacial erosion on Earth.

‘Symmetrodontans’ are extinct mammals characterized by having a reversed-triangle molar pattern in which three main cusps define a triangular molar crown. This dental morpholgy has been regarded as being intermediate between the ‘triconodont’ tooth and the tribosphenic pattern characterizing therians; it is a key feature in taxonomy of Mesozoic mammals and one to understand mammalian evolution and palaeobiology. Here we report a new genus and species of ‘symmetrodontan’ mammal, Lactodens sheni, from the Early Cretaceous Jehol Biota, represented by a partial skeleton with dentary and upper and lower teeth with dental morphologies well-preserved. The new species has a dental formula of three upper incisors, one canine, three premolars, and six molars/three lower incisors, one canine, five premolars and six lower molars, double-rooted canines, extremely low-crowned and transversely thin premolars, and acute angled molars. The dental morphologies of molars and peculiar deciduous premolars are similar to those of Spalacolestes from North America. The associated upper and lower dentitions from one individual animal helped to clarify tooth identification of some spalacotheriids represented only by fragmentary material. Phylogenetic analyses indicate a close relationship of the new species to North American spalacolestines and faunal interchanges between Eurasia and North America, thus supporting the notion that small-bodied spalacotheriids were diverse and had a pan-Laurasian distribution during the Early Cretaceous. Absence of the Meckelian groove suggests acquisition of the definitive mammalian middle ear in spalacolestines, and deciduous canines and premolars in the slim and extremely long dentary imply a faunivorous diet.

The tetrapod forelimb is one of the most versatile structures in vertebrate evolution, having been co-opted for an enormous array of functions. However, the structural relationships between the bones of the forelimb have remained largely unchanged throughout the 375 million year history of Tetrapoda, with a radius and ulna made up of elongate, paralleling shafts contacting a series of shorter carpal bones. These features are consistent across nearly all known tetrapods, suggesting that the morphospace encompassed by these taxa is limited by some sort of constraint(s). Here, we report on a series of three-dimensionally preserved fossils of the small-bodied (less than 1 m) Late Triassic diapsid reptile Drepanosaurus, from the Chinle Formation of New Mexico, USA, which dramatically diverge from this pattern. Along with the crushed type specimen from Italy, these specimens have a flattened, crescent-shaped ulna with a long axis perpendicular to that of the radius and hyperelongate, shaft-like carpal bones contacting the ulna that are proximodistally longer than the radius. The second digit supports a massive, hooked claw. This condition has similarities to living “hook-and-pull” digging mammals and demonstrates that specialized, modern ecological roles had developed during the Triassic Period, over 200 million years ago. The forelimb bones in Drepanosaurus represent previously unknown morphologies for a tetrapod and, thus, a dramatic expansion of known tetrapod forelimb morphospace.

The Neoproterozoic Sturtian glaciation is considered to be among the most severe glaciations in Earth history, possibly encompassing the entire planet and lasting for more than 50 m.y. Iron formations are globally associated with Sturtian glacial successions, although the influence of glaciation on the genesis of these iron formations remains contentious. Here we examine the Sturtian iron formations of Namibia and Australia that feature finely laminated ironstones containing up to 55% total iron. These ironstones are repeatedly interbedded with massive diamictites, yet dropstones and other clastic input are nearly absent in the laminated ironstone facies. Intercalated diamictites are variably ferruginous and characterized by a strong glacial influence with evidence of glaciotectonism. The ferruginous facies are laterally discontinuous and commonly occupy paleobathymetric depressions. Rare earth element signatures from these iron formations are similar to those from modern seawater but lack cerium anomalies. The paradox of dropstone-free, laminated sediments intimately interlaminated with massive ice-proximal diamictites can be resolved by deposition under an ice shelf. Polynya activity and the mixing of cold, oxygenated glacial fluids with ferruginous seawater via an ice pump mechanism may explain the deposition of these iron formations and their restriction to Sturtian glacial successions globally

Friday, September 23, 2016

Bitcoin qualifies as money, a federal judge ruled on Monday, in a decision linked to a criminal case over hacking attacks against JPMorgan Chase & Co and other companies.

U.S. District Judge Alison Nathan in Manhattan rejected a bid by Anthony Murgio to dismiss two charges related to his alleged operation of Coin.mx, which prosecutors have called an unlicensed bitcoin exchange.

Murgio had argued that bitcoin did not qualify as "funds" under the federal law prohibiting the operation of unlicensed money transmitting businesses.

But the judge, like her colleague Jed Rakoff in an unrelated 2014 case, said the virtual currency met that definition.

The origin of rings around giant planets remains elusive. Saturn's rings are massive and made of 90-95% of water ice. In contrast, the much less massive rings of Uranus and Neptune are dark and likely to have higher rock fraction. Here we investigate, for the first time, the tidal disruption of a passing object, including the subsequent formation of planetary rings. First, we perform SPH simulations of the tidal destruction of big differentiated objects (Mbody=1021−23) that experience close encounters with Saturn or Uranus. We find that about 0.1−10% of the mass of the passing body is gravitationally captured around the planet. However, these fragments are initially big chunks and have highly eccentric orbits around the planet. Then, we perform N-body simulations including the planet's oblateness, starting with data obtained from the SPH simulations. Our N-body simulations show that the chunks are tidally destroyed during their next several orbits. Their individual orbits then start to precess incoherently around the planet's equator, which enhances their encounter velocities on longer-term evolution, resulting in more destructive impacts. These collisions would damp their eccentricities resulting in a progressive collapse of the debris cloud into a thin equatorial and low-eccentricity ring. These high energy impacts are expected to be catastrophic enough to produce small particles. Our numerical results also show that the mass of formed rings is large enough to explain current rings including inner regular satellites around Saturn and Uranus. In the case of Uranus, a body can go deeper inside the planet's Roche limit resulting in a more efficient capture of rocky material compared to Saturn's case in which mostly ice is captured. Thus, our results can naturally explain the compositional difference between the rings of Saturn, Uranus and Neptune.

We report on a variety of standard techniques used by New Horizons including a solar ultraviolet occultation, ultraviolet airglow observations, and high-phase look-back particulate search imaging to search for an atmosphere around Pluto's large moon Charon during its flyby in July 2015. Analyzing these datasets, no evidence for a present day atmosphere has been found for 14 potential atomic and molecular species, all of which are now constrained to have pressures below 0.3 nanobar, as we describe below, these are much more stringent upper limits than the previously available 15-110 nanobar constraints (e.g., Sicardy et al. 2006); for example, we find a 3σ upper limit for an N2 atmosphere on Charon is 4.2 picobars and a 3σ upper limit for the brightness of any atmospheric haze on Charon of I/F=2.6x10−5. A radio occultation search for an atmosphere around Charon was also conducted by New Horizons but will be published separately by other authors.

In a press conference on Wednesday, Chinese officials appear to have confirmed what many observers have long suspected: that China is no longer in control of its space station. China's Tiangong-1 space station has been orbiting the planet for about 5 years now, but recently it was decommissioned and the Chinese astronauts returned to the surface. In a press conference last week, China announced that the space station would be falling back to earth at some point in late 2017.

Abelisauroid dinosaurs normally reached an average body length (BL) of 5–9 m, but there are controversies due to the incomplete or fragmentary nature of most specimens. For Ekrixinatosaurus, for example, BL was estimated as 10–11 m or 7–8 m; for Pycnonemosaurus it was proposed 7–8 m, however its preserved bones are larger than any other described abelisauroid. The lack of a consistent methodology complicates comparisons of estimated BL, so we reevaluated the estimative for the seven most complete specimens of abelisauroids and compared the values against 40 measurements from the skull, vertebrae and appendicular elements using bivariate equations. It allowed estimating the BL of other 30, less complete, specimens of abelisauroids and to evaluate the allometric scaling of the skeletal parts. Strong correlations (R2 > 0.96) were obtained for all vertebrae and hindlimb measurements, as well as skull height, and length of skull roof, lacrimal–squamosal, scapulocoracoid and humerus; other skull and forelimb measurements present weak correlation due to extreme morphological transformations observed in Abelisauridae and were not adequate for BL estimation. Abelisauroids gradually increased in size during evolution: the mean BL was 3.3 ± 2.5 m for basal abelisauroids and Noasauridae, 5.4 ± 1.8 m for basal Brachyrostra and Majungasauridae, and 7.1 ± 2.1 m for Furileusaura. Despite this variation, diversity of BL on each geographic region and stratigraphic epoch was relatively constant (BL usually varied from 4 to 8 m). The smallest noasaurid and abelisaurid are, respectively, Velocisaurus (1.5 ± 0.1 m) and Genusaurus (3.6 ± 0.0 m). The largest abelisaurids is Pycnonemosaurus nevesi (8.9 ± 0.3 m) followed by Carnotaurus (7.8 ± 0.3 m), Abelisaurus (7.4 ± 0.7 m) and Ekrixinatosaurus (7.4 ± 0.8 m). Skull measurement scale negatively at a similar rate but the height scales almost isometrically and the skull roof length scales more negatively; this probably caused a bending on the skull that may explain the upward orientation of the snout in large taxa.

Ontogenetic changes in the skull and mandible of thirty-one specimens of Galesaurus planiceps, a basal non-mammaliaform cynodont from the Early Triassic of South Africa, are documented. The qualitative survey indicated eight changes in the craniomandibular apparatus occurred during growth, dividing the sample into three ontogenetic stages: juvenile, subadult, and adult. Changes in the temporal region, zygomatic arch, occiput, and mandible occurred during the transition from the subadult to adult stage at a basal skull length of 90 mm. At least four morphological and allometric differences divided the adult specimens into two morphs, indicating the presence of sexual dimorphism in Galesaurus. Differences include extensive lateral flaring of the zygomatic arches in the ‘male' morph resulting in a more anterior orientation of the orbits, and a narrower snout in the ‘female'. This is the first record of sexual dimorphism in a basal cynodont, and the first time it is quantitatively documented in a non-mammaliaform cynodont. An ontogenetic comparison between Galesaurus and the more derived basal cynodont Thrinaxodon revealed differences in the timing and extent of sagittal crest development. In Galesaurus, the posterior sagittal crest, located behind the parietal foramen, developed relatively later in ontogeny, and the anterior sagittal crest rarely formed suggesting the anterior fibres of the temporalis were less developed than in Thrinaxodon. In contrast, craniomandibular features related to the masseters became more developed during the ontogeny of Galesaurus. The development of the adductor musculature appears to be one of the main factors influencing skull growth in these basal non-mammaliaform cynodonts.

Less than a month ahead of its commissioning, the Navy’s next-generation destroyer Zumwalt (DDG-1000) suffered an engineering casualty that could take up to two weeks to repair, Navy officials confirmed to USNI News on Tuesday.

The ship’s crew – currently pier side at Naval Station Norfolk, Va. – found the fault in the ship’s engineering plant on Sept. 19 ahead of at-sea tests. Zumwalt is now undergoing repairs that may take anywhere from 10 days to two weeks.

“The crew discovered the casualty after detecting a seawater leak in the propulsion motor drive lube oil auxiliary system for one of the ship’s shafts. The built-in redundancy of the ship’s propulsion plant allows this first-in-class ship to operate with multiple engine configurations. However, it was determined that the repairs should be completed in port prior to the ship transiting to sea,” U.S. Naval Surface Forces said in a statement to USNI News.

“Zumwalt will conduct the repairs at Naval Station Norfolk prior to getting underway for training and certification operations.”

There remains substantial debate concerning the relative roles of tectonics and global climate in driving the evolution of climate in Central Asia. Today, interior Asia—including the Taklamakan, Gobi, and Ordos Deserts—is exceptionally arid and is surrounded by distinct rainfall boundaries, such as those generated by the Asian monsoon systems to the east and south and those generated by high topography to the north and west. Determining how and why these boundaries have varied over the Neogene is hindered by the lack of a single proxy that can be broadly applied through space and time. We construct isoscapes of pedogenic carbonate δ13C (δ13Cc) over the Neogene in Asia by combining a compilation of 2236 published measurements with new data from three localities in northern Central Asia. Pedogenic carbonate δ13C records local aridity—excepting localities impacted by C4 grasslands and during large changes in atmospheric pCO2—through variations in soil respiration, depth of carbonate formation, and the effect of water stress on plant δ13C. Together, these effects reflect changes in both primary productivity and mean annual precipitation. Throughout the Neogene, we find consistent and exceptionally high δ13Cc in interior Asia with a ring of lower δ13Cc that demarcates higher precipitation. This persistent ring of lower δ13Cc corresponds in the south and east with the influence of the Asian monsoon systems; in the west and north, it reflects both orographic rainfall due to uplift of the Tian Shan and to moisture delivery by the mid-latitude westerlies. Finally, δ13Cc and, hence, aridity increases regionally in the latest Neogene, reflecting the effects of Northern Hemisphere glaciation and cooling. This widespread "de-greening" would have increased regional albedo and modified basin-scale water balances, resulting in greater dust fluxes due to reduced vegetative cover and precipitation.

Eleven species of archaeopterodactyloid pterosaurs have been reported in China, mostly from the Yixian Formation of western Liaoning. The first uncontroversial archaeopterodactyloid from the Jiufotang Formation is described here. A new genus and species, Forfexopterus jeholensis, is erected on the basis of a unique combination of characters and one autapomorphy: the first wing phalanx is shorter than the second, but longer than the third. The sternum of Forfexopterus is nearly complete and provides the first incontrovertible evidence about the position of sternocoracoid articulations in the Archaeopterodactyloidea. A preliminary geometric morphometric analysis of sterna was carried out with data from 17 species of Pterodactylomorpha. The results document the variation in the shape of the sternum, including the length of the cristospine, the shapes of the lateral, posterior, and anterior margins, and the constriction and expansion of the cristospine. These characters can be used to compare sterna in different pterosaur taxa.

The origin of tetrapods is one of the key events in vertebrate history. The oldest tetrapod body fossils are Late Devonian (Frasnian–Famennian) in age, most of them consisting of rare isolated bone elements. Here we describe tetrapod remains from two Famennian localities from Belgium: Strud, in the Province of Namur, and Becco, in the Province of Liège. The newly collected material consists of an isolated complete postorbital, fragments of two maxillae, and one putative partial cleithrum, all from Strud, and an almost complete maxilla from Becco. The two incomplete maxillae and cleithrum from Strud, together with the lower jaw previously recorded from this site, closely resemble the genus Ichthyostega, initially described from East Greenland. The postorbital from Strud and the maxilla from Becco do not resemble the genus Ichthyostega. They show several derived anatomical characters allowing their tentative assignment to a whatcheeriid-grade group. The new tetrapod records show that there are at least two tetrapod taxa in Belgium and almost certainly two different tetrapod taxa at Strud. This locality joins the group of Devonian tetrapod-bearing localities yielding more than one tetrapod taxon, confirming that environments favourable to early tetrapod life were often colonized by several tetrapod taxa.

Coastal-plain paleosols in the 3.0 Ga Farrel Quartzite of Western Australia have organic surface (A horizon) and sulfate-rich subsurface (By) horizons, like soils of the Atacama Desert of Chile, Dry Valleys of Antarctica, and 3.7 Ga paleosols of Mars. Farrel Quartzite paleosols include previously described microfossils, permineralized by silica in a way comparable with the Devonian Rhynie Chert, a well known permineralized Histosol. Five microfossil morphotypes in the Farrel Quartzite include a variety of spheroidal cells (Archaeosphaeroides) as well as distinctive large spindles (new genus provisionally assigned to cf. Eopoikilofusa). Previously published cell-specific carbon isotopic analyses of the Farrel Quartzite microfossils, and unusually abundant sulfate considering a likely anoxic atmosphere, allow interpretation of these morphotypes as a terrestrial community of actinobacteria, purple sulfur bacteria, and methanogenic Archaea.

A high-level Indian delegation will be visiting Russia shortly to finalize an agreement on renting the Yasen class submarine for the Indian Navy. Government sources told Sputnik that renting the second nuclear powered attack submarine from Russia would result in the introduction of newer technology into India, which would eventually pave the way for Russian collaboration with India for it program to build six new SSN.

Friday, September 16, 2016

Previous estimates of the surface temperature of Jupiter's moon, Europa, neglected the effect of the eccentricity of Jupiter's orbit around the Sun, the effect of the eclipse of Europa (i.e., the relative time that Europa is within the shadow of Jupiter), and the effect of Europa's internal heating. Here we estimate the surface temperature of Europa, when Europa's obliquity, eclipse and internal heating, as well as the eccentricity of Jupiter, are all taken into account. For a typical internal heating rate of 0.05 W/m2 (corresponding to an ice thickness of about 10 kms), the equator, pole, and global mean surface temperatures are 101.7 K, 45.26 K, and 94.75 K, respectively. We found that the temperature at the high latitudes is significantly affected by the internal heating. We also studied the effect of the internal heating on the mean thickness of Europa's icy shell and conclude that the polar region temperature can be used to constrain the internal heating and the depth of the ice. Our approach and formalism can be implemented to estimate the temperature of other moons in the solar system.

Although the majority of Centaurs are thought to have originated in the scattered disk, with the high-inclination members coming from the Oort cloud, the origin of the high inclination component of trans-Neptunian objects (TNOs) remains uncertain. We report the discovery of a retrograde TNO, which we nickname "Niku", detected by the Pan-STARRS 1 Outer Solar System Survey. Our numerical integrations show that the orbital dynamics of Niku are very similar to that of 2008 KV42 (Drac), with a half-life of ∼500 Myr. Comparing similar high inclination TNOs and Centaurs (q>10 AU, a<100 and="" au="" i="">60∘), we find that these objects exhibit a surprising clustering of ascending node, and occupy a common orbital plane. This orbital configuration has high statistical significance: 3.8-σ. An unknown mechanism is required to explain the observed clustering. This discovery may provide a pathway to investigate a possible reservoir of high-inclination objects. 100>

For decades, scientists have tried to explain the evidence for fluvial activity on early Mars, but a consensus has yet to emerge regarding the mechanism for producing it. One hypothesis suggests early Mars was warmed by a thick greenhouse atmosphere. Another suggests that early Mars was generally cold but was warmed occasionally by impacts or by episodes of enhanced volcanism. These latter hypotheses struggle to produce the amounts of rainfall needed to form the martian valleys, but are consistent with inferred low rates of weathering compared to Earth. Here, we provide a geophysical mechanism that could have induced cycles of glaciation and deglaciation on early Mars. Our model produces dramatic climate cycles with extended periods of glaciation punctuated by warm periods lasting up to 10 Myr, much longer than those generated in other episodic warming models. The cycles occur because stellar insolation was low, and because CO2 outgassing is not able to keep pace with CO2 consumption by silicate weathering followed by deposition of carbonates. While CO2 by itself is not able to deglaciate early Mars in our model, we assume that the greenhouse effect is enhanced by substantial amounts of H2 outgassed from Mars' reduced crust and mantle. Our hypothesis can be tested by future Mars exploration that better establishes the time scale for valley formation.

Years in the making, but finally revealed on Monday, Blue Origin’s New Glenn rocket has been shown for the first time via its founder Jeff Bezos. Arriving in two variants, the new – and surprisingly powerful – orbital rocket is scheduled to debut from Cape Canaveral’s SLC-36 by the end of the decade. Like its suborbital sister – the New Shepard – its booster stage will be reusable.

The first in a class of new guided missile destroyer has left its Maine shipyard to start a three-month journey to its homeport in San Diego, Calif.

Zumwalt (DDG-1000) headed to the Atlantic down the Kennebec River from its berth at the General Dynamics Bath Iron Works shipyard on Wednesday, the Navy announced.

Following the ship’s planned commissioning in Baltimore on Oct. 15, the ship will then transit to California for a post-delivery maintenance availability focused on activating the ship’s combat system. The ship is set to be “integrated into the fleet” by 2018, the service said on Wednesday.

Scientists
today announced the discovery of a new species of pterosaur from the
Patagonia region of South America. The cranial remains were in an
excellent state of preservation and belonged to a new species of
pterosaur from the Early Jurassic. The researchers have named this new
species 'Allkauren koi' from the native Tehuelche word 'all' for
'brain', and 'karuen' for 'ancient'.

Pterosaurs are an
extinct group of flying reptiles that lived during most of the Mesozoic
Era. This group had an extraordinary adaptation to flight, including
pneumatic bones to lighten its weight, and an elongated digit supporting
a wing membrane. However, pterosaur neuroanatomy is known from only a
few three dimensionally preserved remains and, until now, there was no
information on the intermediate forms. This study therefore provides new
information on the origin, tempo and mode of evolution in this
particular group of flying reptiles.

The fossil of
Allkaruen koi was found in northern central Chubut Province, Patagonia
Argentina and the remains included a superbly preserved and uncrushed
braincase. In order to study the neurocranial anatomy, researchers used
computed tomography to observe, in three dimensions, the cranial
endocast and the inner ear. Subsequently, a comprehensive phylogenetic
analysis of the group was performed, including these cranial data and
other anatomical features. "Allkaruen, from the middle lower jurassic
limit, shows an intermediate state in the brain evolution of pterosaurs
and their adaptations to the aerial environment", said Dr Diego Pol, who
is part of the research team. "As a result, this research makes an
important contribution to the understanding of the evolution of all of
pterosaurs."