Three years ago, security consultant Dragos Ruiu was in his lab when he noticed something highly unusual: his MacBook Air, on which he had just installed a fresh copy of OS X, spontaneously updated the firmware that helps it boot. Stranger still, when Ruiu then tried to boot the machine off a CD ROM, it refused. He also found that the machine could delete data and undo configuration changes with no prompting. He didn't know it then, but that odd firmware update would become a high-stakes malware mystery that would consume most of his waking hours.link.
In the following months, Ruiu observed more odd phenomena that seemed straight out of a science-fiction thriller. A computer running the Open BSD operating system also began to modify its settings and delete its data without explanation or prompting. His network transmitted data specific to the Internet's next-generation IPv6 networking protocol, even from computers that were supposed to have IPv6 completely disabled. Strangest of all was the ability of infected machines to transmit small amounts of network data with other infected machines even when their power cords and Ethernet cables were unplugged and their Wi-Fi and Bluetooth cards were removed. Further investigation soon showed that the list of affected operating systems also included multiple variants of Windows and Linux.
"We were like, 'Okay, we're totally owned,'" Ruiu told Ars. "'We have to erase all our systems and start from scratch,' which we did. It was a very painful exercise. I've been suspicious of stuff around here ever since."
In the intervening three years, Ruiu said, the infections have persisted, almost like a strain of bacteria that's able to survive extreme antibiotic therapies. Within hours or weeks of wiping an infected computer clean, the odd behavior would return. The most visible sign of contamination is a machine's inability to boot off a CD, but other, more subtle behaviors can be observed when using tools such as Process Monitor, which is designed for troubleshooting and forensic investigations.
Another intriguing characteristic: in addition to jumping "airgaps" designed to isolate infected or sensitive machines from all other networked computers, the malware seems to have self-healing capabilities.
"We had an air-gapped computer that just had its [firmware] BIOS reflashed, a fresh disk drive installed, and zero data on it, installed from a Windows system CD," Ruiu said. "At one point, we were editing some of the components and our registry editor got disabled. It was like: wait a minute, how can that happen? How can the machine react and attack the software that we're using to attack it? This is an air-gapped machine and all of the sudden the search function in the registry editor stopped working when we were using it to search for their keys."
Thursday, October 31, 2013
Keeping with the Scary Halloween Theme: Meet badBIOS, the Malware Which Can Infect Across Air Gaps
Must be Titled With a Sense of Irony: Can “Skynet” and “the Borg” Solve EW and Cyber Challenges?
People fear drones. People fear “killer robots.” People fear death by push button. People need to put away their fears and remember that computing power, coupled with automation and rules-based decision-making, has saved many lives and is likely to save many more than any runaway robot ever will.
That was the general consensus of a group of experts here at the annual meeting of the military’s electronic warfare experts discussing the provocatively titled subject: Can “Skynet” and “the Borg” Solve EW and Cyber Challenges?
The short answer was yes, probably. The long answer was, yes, probably, but it’s a long way off. Panelist Harry Wingo, former counsel to Google and to the Senate Commerce Committee, said he wished he was smart enough to come up with Wingo’s Law, which would predict the rate at which robots would save lives.
“There are going to be so many instance of robotics saving lives,” he said, offering the example of the combination of robotic defibrillators. A passerby who witnessed what looks like a heart attack could open an emergency app and hail a defibrillator which would respond more quickly and efficiently than would an emergency medical technician.
But on the issue of automated weapons that can kill people, the issues of fear and ethics are clearly still being grappled with at the Pentagon and in society at large. For example, Friedman ointed to the Flash Crash of May 6, 2010 when the market fell almost 1,000 points in a matter of minutes. “We have absolutely no idea what happened,” he noted of the automated trading disaster. That, of course, leaves commanders and policymakers wary of automated actions.
David Slayton, fellow at the conservative Hoover Institution, citing conversations with senior officials, said “there is a certain degree of discomfort with determining where you are going to achieve control over that kill chain.” That raises the question if we then “allow the next step to an automated system.”
Automated systems, of course, don’t get angry and are unlikely to order a retributive strike or to lose control and keep shooting after the target is killed. “Machines have the advantage over us in that they are a bit cooler and dispassionate, because they are machines,” Wingo said.
The issue is greatly complicated because there are clearly different types of attacks in the electronic world, which is what this panel was most closely focused on. Most attacks in the electronic world would be considered espionage or criminal activity. The financial world is most advanced in launching automated electronic actions, as everyone who has ever read about high-speed trading and hedge funds knows. Problems with those have wreaked havoc the cause of which is still not completely understood, said panelist Allan Friedman, an expert at the Brookings Institution.
Extend automated capabilities to electronic warfare and cyber weapons and you really raise few questions distinctive from those any military has to grapple with in deciding when and where to kill an enemy or to destroy their weapons.
In an interesting piece, the Air Force’s top lawyer offered this opinion last year in an official blog on “killer robots:”
link.
I am hoping and praying this is meant as an ironic twist just for Halloween.
Right? Right???? Right??????!?!?!?!?!
Captain James Kirk Takes Command (not kidding) of the USS Zumwalt
link.
The officer has probably earned it, but, damn, if it doesn't seem like the Navy is a bunch of Trekkies...
Mars One Claims to Fly Unmanned Martian Lander in 2016
Mars One will send “a small craft that will demonstrate the technologies we need for our human colony” and is inviting partners to join the mission…
The first step is to test whether conditions for sustaining humans can be created, by sending experimental systems on a lander.
“If you have a reason to get something to Mars, get in touch with me,” Lansdorp told the conference.
“It could be a country that wants to do an experiment on Martian soil.
“I know the UK space agency has been interested in getting to Mars in the past. They could put something on our lander and get a payload there.
“We also have consumer firms that are interested in becoming ‘the first brand on Mars’.”
Another idea is to allow a “high schools payload” similar to the recent Youtube Space Lab.
This is my raised, disbelieving eyebrow.
link via Parabolic Arc.
OGLE-2012-BLG-0358Lb: Jovian Planet Found Around Brown Dwarf
MICROLENSING DISCOVERY OF A TIGHT, LOW-MASS-RATIO PLANETARY-MASS OBJECT AROUND AN OLD FIELD BROWN DWARF
Authors:
Han et al
Abstract:
Observations of accretion disks around young brown dwarfs (BDs) have led to the speculation that they may form planetary systems similar to normal stars. While there have been several detections of planetary-mass objects around BDs (2MASS 1207-3932 and 2MASS 0441-2301), these companions have relatively large mass ratios and projected separations, suggesting that they formed in a manner analogous to stellar binaries. We present the discovery of a planetary-mass object orbiting a field BD via gravitational microlensing, OGLE-2012-BLG-0358Lb. The system is a low secondary/primary mass ratio (0.080 ± 0.001), relatively tightly separated (~0.87 AU) binary composed of a planetary-mass object with 1.9 ± 0.2 Jupiter masses orbiting a BD with a mass 0.022 M ☉. The relatively small mass ratio and separation suggest that the companion may have formed in a protoplanetary disk around the BD host in a manner analogous to planets.
Planetary Systems Seem to be Forming Around Class A Stars HD 131488 and HD 121191
COPIOUS AMOUNTS OF HOT AND COLD DUST ORBITING THE MAIN SEQUENCE A-TYPE STARS HD 131488 AND HD 121191
Authors:
Melis et al.
Abstract:
We report two new dramatically dusty main sequence stars: HD 131488 (A1 V) and HD 121191 (A8 V). HD 131488 is found to have substantial amounts of dust in its terrestrial planet zone (L IR/L bol ≈ 4 × 10–3), cooler dust farther out in its planetary system, and an unusual mid-infrared spectral feature. HD 121191 shows terrestrial planet zone dust (L IR/L bol ≈ 2.3 × 10–3), hints of cooler dust, and shares the unusual mid-infrared spectral shape identified in HD 131488. These two stars belong to sub-groups of the Scorpius-Centaurus OB association and have ages of ~10 Myr. HD 131488 and HD 121191 are the dustiest main sequence A-type stars currently known. Early-type stars that host substantial inner planetary system dust are thus far found only within the age range of 5-20 Myr.
Marrella-like Arthropod Fossil From Cambrian Australia Links Oresten-type and Burgess Shale Assemblages
A Marrella-like arthropod from Cambrian of Australia: A new link between "Orsten"-type and Burgess Shale assemblages
Authors:
Haug et al
Abstract:
An isolated exopod in uncompressed three−dimensional “Orsten”−type preservation from the Cambrian of Australia represents a new species of Marrellomorpha, Austromarrella klausmuelleri gen. et sp. nov. The exopod is composed of at least 17 annuli. Each of the proximal annuli carries a pair of lamellae: one lamella on the lateral side and one on the median side. The distal annuli bear stout spines in the corresponding position instead of lamellae, most likely representing early ontogenetic equivalents of the lamellae. The new find extends the geographical range of the taxon Marrellomorpha. Additionally, it offers a partial view into marrellomorph ontogeny. The occurrence of a marrellomorph fragment in “Orsten”−type preservation provides new palaeo−ecological insights into the possible connections between the “Orsten” biotas and other fossil Lagerstätten. Finding such connections is necessary for understanding the complex ecosystems of early Palaeozoic times.
Mistralestes and Valentinella: New Eutherian Mammals From Campanian and Maastrichtian Cretaceous France
New eutherian mammals from the Late Cretaceous of Aix-en-Provence Basin, south-eastern France
Authors:
Tabuce et al
Abstract:
In Europe, the fossil record of Late Cretaceous eutherian mammals is very poor, being limited to only three genera (Labes, Lainodon, and Valentinella). Labes and Lainodon are well-supported members of Zhelestidae, a stem eutherian clade, whereas Valentinella is more problematic, being recently considered as a nomen dubium. Based on X-ray computed microtomography scan analysis of the holotype and thanks to the discovery of new specimens from the type locality (Vitrolles-La Plaine, south-eastern France, late Maastrichtian), we reassessed Valentinella. This genus is unique by the association of an enlarged and rounded jaw angle with an assumed relatively elevated angular process, a bulbous protoconid and an unbasined heel on p4, a p5 with a wide molariform talonid and a hypoflexid, a robust molar morphology with a potential specialized crushing-grinding function (bulbously constructed cusps, large talonid, and horizontal apical wear facet of the hypocone), a somewhat reduced m3 relative to m2, a premolariform ?P3 or ?P4 lacking a metacone, and a relatively large hypocone on upper molars. These characters reinstate Valentinella as a valid genus. We also describe Mistralestes arcensis gen. et sp. nov. from a newly discovered locality (La Cairanne-Highway, south-eastern France, late Campanian). Mistralestes is defined by a robust premolariform p5 with no cingulid, paraconid, or metaconid; molars with a transverse protocristid, a gradual compression of the trigonid from m1 to m3, and paracristid and protocristid probably confluent on m3. Based on comparisons and phylogenetic analyses, Valentinella and Mistralestes may belong to Zhelestidae but this systematic attribution remains poorly supported.
North China Craton Shows Rifting Within Statherian PaleoProterozoic Supercontinent Columbia
Wang et al
Abstract:The Yanliao rift zone along the northern margin of the North China Craton exposes a suite of volcanic rocks comprising trachybasalts and trachytes interlayered with dolostones in the Tuanshanzi Formation of the Changcheng Group. The overlying Dahongyu Formation is composed of olivine basalts, trachybasalts, trachyandesites, trachytes, and minor sub-alkaline basalts, intercalated with a lower sandstone and an upper dolostone sequence. LA-ICP-MS zircon U-Pb age data from the volcanics reveal that the Tuanshanzi Formation was deposited at ca. 1670 Ma, and the Dahongyu Formation at ca. 1625–1664 Ma. Combined with previous studies, these new data indicate that the lowest boundary age of the Changcheng Group, marking the timing of initiation of the Yanliao rift, is ca. 1680 Ma. Except for the sub-alkaline basalts, the other alkaline volcanic rocks of the two formations are characterized by high Nb/Y ratios (1–3), and possess SiO2 contents of 43.3-60.5 wt.%, K2O of 0.72-15.69 wt.%, MgO of 0.10-8.56 wt.%, and with Mg# of 2–64. These rocks also display strongly fractionated REE patterns and generally positive Nb and Ta anomalies, with high (Nb/La)PM and (Nb/Th)PM values of 0.85-1.39 and 0.96-2.05, respectively. They show positive zircon εHf(t) values (+ 0.1 to + 1.8 for the trachybasalt sample 11PG31-2) and whole-rock εNd(t) values (+ 0.83 to + 2.25). These geochemical features, together with trace element modeling, suggest that the alkaline volcanic rocks were generated by fractional crystallization of magma derived from low-degree partial melting of an OIB-like depleted asthenospheric mantle source, with only minor involvement of melts generated from the overlying enriched lithospheric mantle source. In contrast, the sub-alkaline basalts are characterized by low Nb/Y ratios of 0.09-0.19, and show fractionated REE patterns and pronounced negative Nb-Ta anomalies with low (Nb/La)PM and (Nb/Th)PM values of 0.07-0.21 and 0.10-0.33, respectively. In combination with the positive zircon εHf(t) values (+ 0.8- + 4.3), we infer that these rocks were derived from the partial melting of a depleted lithospheric mantle source previously metasomatized by fluids from subducted slab. Combined with previous studies on the 1680–1780 Ma magmatic rocks along the northern margin of the NCC, our study identifies a late Paleoproterozoic asthenospheric upwelling in this region. The generation of the Yanliao rift and the eruption of these volcanic rocks were possibly triggered by the delamination of the continental lithosphere in a post-orogenic setting following the final amalgamation of the North China Craton within the Columbia supercontinent.
China in Africa: The $1 Billion Loan to Niger
Niger has accepted a controversial $1 billion loan from the Export-Import Bank of China (China Exim Bank) to finance development projects, the West African nation's planning minister said Tuesday.
Repayment of the 25-year loan will start in eight years' time "thanks to resources from the sale of oil being produced" by China National Petroleum Corporation (CNPC) in the east of the country, Amadou Boubacar Cisse announced.
The agreement, the conditions of which Cisse said were "very favourable", was signed in China on September 30.
Details were not immediately available, but typically China Exim Bank loans require the borrower nation to allocate work and equipment contracts for the project to Chinese companies.
link.
Lockheed Signs Deal with China to Build World's Largest (10 megawatt) Ocean Thermal Power Plant
Leading U.S. defense contractor Lockheed Martin signed a contract on Wednesday to design the biggest power station fueled by differences in ocean temperatures, a 10-megawatt plant that would provide electricity for a new Asian resort.
The contract between Lockheed and Beijing-based Reignwood Group, a Chinese consumer products and lifestyle firm, is the initial 10-month stage in a 3-1/2-year effort to build the green energy electric plant, which would generate power using a process known as ocean thermal energy conversion (OTEC).
"This is just more or less the tip of the iceberg and what both parties are most interested in is ultimately getting the plant built so we can offer it to other customers. And that's where the business is for Lockheed," said Dan Heller, vice president of new ventures for Lockheed's Mission Systems and Training unit.
Heller declined to say how much the contract is worth for Lockheed or to estimate the potential cost of constructing the facility, which uses a process that has been tested in smaller plants but has never been developed on a commercial scale.
Other companies and organizations are pursuing OTEC energy projects as well. But Heller said the facility planned for Reignwood would "be magnitudes larger than anybody else, including ourselves, have ever attempted."
Heller said the two firms agreed to an initial 10-month contract for design of the plant because of the uncertainty surrounding the ultimate cost of a small commercial-scale facility. He said the design phase would help clarify the cost.
link.
Wednesday, October 30, 2013
More Academic Bun Fight: The Younger Dryas Impact Argument Continues (And Starts Getting...Sharp)
Younger Dryas impact model confuses comet facts, defies airburst physics
Authors:
Boslough et al
Excerpt:
In PNAS, Wittke et al. (1) present evidence that they indicate supports major airbursts and/or impacts at the beginning of the Younger Dryas, as proposed by Firestone et al. (2). One of the major criticisms of the hypothesis has been the lack of any physics-based model for the hypothesized event (3). Wittke et al. (1) attempt to remedy this flaw by including a section entitled “Preliminary Impact Model.” Their model diverges significantly from the original but still provides no physics based argument and demonstrates a misunderstanding of comets, as well as the physics of airbursts.
Counterargument:
Reply to Boslough et al.: Decades of comet research counter their claims
Authors:
Napier et al
Excerpt:
Boslough et al. (1) offer no alternate explanation for ∼10 million tonnes of Younger Dryas spherules recovered from 18 sites across ∼50 million square kilometers of North America, Europe, and the Middle East (2). In addition, the authors claim that our hypothesis “demonstrates a misunderstanding of comets.” However, the misunderstanding is theirs alone, because the model they criticize is their own creation and not the one we adopt, which derives from a substantial body of comet literature (e.g., ref. 3).
And its getting personal...
Siberian Skeleton Hints Native Americans Have Some PreColumbian, PreViking European Roots
Where did the first Americans come from? Most researchers agree that Paleoamericans moved across the Bering Land Bridge from Asia sometime before 15,000 years ago, suggesting roots in East Asia. But just where the source populations arose has long been a mystery.
Now comes a surprising twist, from the complete nuclear genome of a Siberian boy who died 24,000 years ago—the oldest complete genome of a modern human sequenced to date. His DNA shows close ties to those of today's Native Americans. Yet he apparently descended not from East Asians, but from people who had lived in Europe or western Asia. The finding suggests that about a third of the ancestry of today's Native Americans can be traced to "western Eurasia," with the other two-thirds coming from eastern Asia, according to a talk at a meeting* here by ancient DNA expert Eske Willerslev of the University of Copenhagen. It also implies that traces of European ancestry previously detected in modern Native Americans do not come solely from mixing with European colonists, as most scientists had assumed, but have much deeper roots.
"I'm still processing that Native Americans are one-third European," says geneticist Connie Mulligan of the University of Florida in Gainesville. "It's jaw-dropping." At the very least, says geneticist Dennis O'Rourke of the University of Utah in Salt Lake City, "this is going to stimulate a lot of discussion."
Researchers have been trying to parse the origins of the first Americans for decades. Most agree that people moved across Beringia, via a vast ice age land bridge (see map p. 410), and began spreading through the Americas, reaching Chile by 14,500 years ago. But the origins of the source populations are not clear, and some archaeologists have even suggested that ancient Europeans crossing the Atlantic were part of the mix (Science, 16 March 2012, p. 1289). Others have contended that early skeletons found in the Americas, such as the 9000-year-old Kennewick Man, show some European features (Science, 10 April 1998, p. 190). In his talk, Willerslev argued that the ancient genome "can actually explain a lot of these inconsistencies," by offering glimpses of prehistoric populations before more recent migrations and other demographic events blurred the picture.
The genome comes from the right upper arm bone of a boy aged about 4 years, who lived by Siberia's Belaya River. Those who buried him adorned his grave with flint tools, pendants, a bead necklace, and a sprinkling of ochre. In the 1920s, Russian archaeologists discovered the burial and other artifacts near a village called Mal'ta, which gave the celebrated site its name. Willerslev and co-author Kelly Graf of Texas A&M University in College Station, traveled to the State Hermitage Museum in St. Petersburg, Russia, where the boy's remains are housed, and took a bone sample.
Willerslev reported that the team was able to sequence the boy's genome, and also to radiocarbon date the bone. The team then used a variety of statistical methods to compare the genome with that of living populations. They found that a portion of the boy's genome is shared only by today's Native Americans and no other groups, showing a close relationship. Yet the child's Y chromosome belongs to a genetic group called Y haplogroup R, and its mitochondrial DNA to a haplogroup U. Today, those haplogroups are found almost exclusively in people living in Europe and regions of Asia west of the Altai Mountains, which are near the borders of Russia, China, and Mongolia.
One expected relationship was missing from the picture: The boy's genome showed no connection to modern East Asians. DNA studies of living people strongly suggest that East Asians—perhaps Siberians, Chinese, or Japanese—make up the major part of Native American ancestors. So how could the boy be related to living Native Americans, but not to East Asians? "This was kind of puzzling at first," Willerslev told the meeting. But there seemed little doubt that the finding was correct, he said, because nearly all Native Americans from North and South America were equally related to the Mal'ta child, indicating that he represented very deep Native American roots.
link.
USS Zumwalt, the Destroyer as Big as WW2 Heavy Cruisers, Launched
General Dynamics Bath Iron Works (BIW) successfully launched the Navy’s first Zumwalt-class destroyer Oct. 28 at their Bath, Maine shipyard. The future USS Zumwalt (DDG 1000) will be the lead ship of the Navy’s newest destroyer class, designed for littoral operations and land attack. At 610 feet (186 meter) long, and 15,610 (long) tons displacement, the Zumwalt looks unlike any ship the navy has sailed, with an angular superstructure, a low-slung “tumblehome” hull to “pierce” waves for a smoother ride, Other new provisions include electric propulsion and a futuristic bridge, that looks more like it belongs on Star Trek’s USS Enterprise than a real Navy ship.link.
The $4 billion warship, built by Bath Iron Works in Maine, was launched on the Kennebec River Monday, five years after construction began. The Zumwalt, hull number DDG-1000, was meant to be the first of a class to replace the DDG-51 Arleigh Burke-class destroyers. Rising construction costs caused caused the Pentagon to tack, limiting the program to just three Zumwalts. They are 100 feet longer than their predecessor, but require half the crew.
Warming of Permafrost on Siberian Coast is Greatly Increasing Erosion
This photo illustration shows the erosion of the east-Siberian island Muostakh. The blue line marks ist coastal line in the year 1951, the red line presents its status in the year 2012. In the upper right corner one can see an aerial picture of the island's northern tip, taken in the year 2012. At its narrowest point the island is shrinking more than four meters per year.
The high cliffs of Eastern Siberia – which mainly consist of permafrost – continue to erode at an ever quickening pace. This is the conclusion which scientists of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research have reached after their evaluation of data and aerial photographs of the coastal regions for the last 40 years. According to the researchers, the reasons for this increasing erosion are rising summer temperatures in the Russian permafrost regions as well the retreat of the Arctic sea ice. This coastal protection recedes more and more on an annual basis. As a result, waves undermine the shores. At the same time, the land surface begins to sink. The small island of Muostakh east of the Lena Delta is especially affected by these changes. Experts fear that it might even disappear altogether should the loss of land continue.link.
The interconnectedness is clear and unambiguous: The warmer the east Siberian permafrost regions become, the quicker the coast erodes. "If the average temperature rises by 1 degree Celsius in the summer, erosion accelerates by 1.2 meters annually," says AWI geographer Frank Günther, who investigates the causes of the coastal breakdown in Eastern Siberia together with German and Russian colleagues, and who has published his findings in two scientific articles.
Kepler-78b: A DOOMED Earth Sized World of (probably) Burning Lava
Kepler-78b is a planet that shouldn't exist. This scorching lava world circles its star every eight and a half hours at a distance of less than one million miles - one of the tightest known orbits. According to current theories of planet formation, it couldn't have formed so close to its star, nor could it have moved there.
"This planet is a complete mystery," says astronomer David Latham of the Harvard-Smithsonian Center for Astrophysics (CfA). "We don't know how it formed or how it got to where it is today. What we do know is that it's not going to last forever."
"Kepler-78b is going to end up in the star very soon, astronomically speaking," agrees CfA astronomer Dimitar Sasselov.
Not only is Kepler-78b a mystery world, it is the first known Earth-sized planet with an Earth-like density. Kepler-78b is about 20 percent larger than the Earth, with a diameter of 9,200 miles, and weighs almost twice as much. As a result it has a density similar to Earth's, which suggests an Earth-like composition of iron and rock.
The tight orbit of Kepler-78b poses a challenge to theorists. When this planetary system was forming, the young star was larger than it is now. As a result, the current orbit of Kepler-78b would have been inside the swollen star.
"It couldn't have formed in place because you can't form a planet inside a star. It couldn't have formed further out and migrated inward, because it would have migrated all the way into the star. This planet is an enigma," explains Sasselov.
According to Latham, Kepler-78b is a member of a new class of planets recently identified in data from NASA's Kepler spacecraft. These newfound worlds all orbit their stars with periods of less than 12 hours. They're also small, about the size of Earth. Kepler-78b is the first planet in the new class to have its mass measured.
"Kepler-78b is the poster child for this new class of planets," notes Latham.
link. 2nd link. 3rd link.
KOI-351 Appears to Have Seven Exoplanets Within One AU (the Orbit of Earth)
A team of astrophysicists at the German Aerospace Center (Deutsches Zentrum für Luft und- Raumfahrt; DLR), together with German and other European colleagues, has discovered the most extensive planetary system to date. Seven planets circle the star KOI-351 – more than in other known planetary systems. They are arranged in a similar fashion to the eight planets in the Solar System, with small rocky planets close to the parent star and gas giant planets at greater distances. Although the planetary system around KOI-351 is packed together more tightly, it provides an interesting comparison to our cosmic home.
Important step in the search for a 'twin Solar System'
Astrophysicists around the world have been searching for a star system similar to our own for a long time. Now, the team led by Juan Cabrera, an astrophysicist at the DLR Institute of Planetary Research in Berlin-Adlershof has taken a major step in this direction. Three of the seven planets in orbit around the star KOI-351 were discovered in recent years, and have periods of 331, 211 and 60 days, similar to those of Earth, Venus and Mercury.
The planets discovered by Cabrera and his team are even closer to the star and have orbital periods of 7, 9, 92 and 125 days. The outermost planet orbits the star at a distance of about 150 million kilometres, or roughly one Astronomical Unit (AU), so the entire planetary system is compressed into a space corresponding to the distance between Earth and the Sun.
In the article published in the Astrophysical Journal, Juan Cabrera and his colleagues emphasise the similarities between KOI-351 and the Solar System: "No other planetary system shows such a similar 'architecture' to that of our cosmic home as does the planetary system around KOI-351," says Cabrera. "Just as in the Solar System, rocky planets with roughly the size of Earth are found close to the star, while, 'gas giants' similar to Jupiter and Saturn are found as you move away from the star."
"We cannot stress just how important this discovery is. It is a big step in the search for a 'twin' to the Solar System, and thus also in finding a second Earth," said Cabrera. Heike Rauer, head of the Extrasolar Planets and Atmospheres working group at the DLR Institute of Planetary Research and professor at the Centre for Astronomy and Astrophysics at the University of Berlin, adds: "The discovery of this complex planetary system helps us to better understand the processes that give rise to such planetary systems." Tilman Spohn, Head of the DLR Institute of Planetary Research states that: "DLR is proud to have made a significant contribution to the discovery of new planetary systems."
Specially developed computer program enabled discovery
The development of a special computer algorithm enabled Juan Cabrera and his team to detect the four new planets around KOI-351. The DLR astrophysicist was able to filter out the light curves that reveal the 'transit' of a planet across its parent star from the Kepler measurements. A transit is inferred from the small, periodic dimming of the star's light as the planet crosses the star's disc. This technological development is likely to be crucial in the search for similar multiple systems using large data sets from future space telescopes. The discovery was confirmed shortly afterwards by a US group led by Joseph R. Schmitt of Yale University, by visual inspection of the light curves recorded by Kepler.
KOI is the abbreviation for 'Kepler Object of Interest', which means the star was observed by NASA's Kepler space telescope, between 2008 and 2013, and classified as a candidate for the existence of exoplanets. At present, KOI-351 is the star with the most extrasolar planets, or exoplanets for short. The star is 2500 light years away from Earth.
Unusual resonances between the planets
"The resonances of the planetary orbits are another interesting feature of this system," explains Szilárd Csizmadia, a member of the team led by Cabrera. Orbital resonance occurs when two or more orbiting bodies exert a regular, periodic gravitational influence on one another. "Resonances also play an important role in the Solar System; for example, the moons of Jupiter. So KOI-351 is a gold mine for all researchers investigating planetary formation and the stability of multi-body systems."
The resonances in the planetary system of KOI-351, however, greatly complicated the search for the planets. Due to the strong interaction between the planets, the signals sought by Juan Cabrera in the Kepler data were not strictly periodic, but showed strong variations in the orbital periods. Rudolf Dvorak of the University of Vienna highlights the planet KOI-351g as being particularly interesting: "The orbital period of planet g varies by about a day between consecutive transits during the observations. Disturbances of this kind have been noted previously, but so far only with maximum deviations of a few minutes."
link,
Modeling the Locomotion of Sauropod Argentinosaurus huinculensis (with video)
March of the Titans: The Locomotor Capabilities of Sauropod Dinosaurs
Authors:
William Irvin Sellers, Lee Margetts, Rodolfo Anı´bal Coria and Phillip Lars Manning
Abstract:
Sauropod dinosaurs are the largest terrestrial vertebrate to have lived on Earth. This size must have posed special challenges for the musculoskeletal system. Scaling theory shows that body mass and hence the loads that must be overcome increases with body size more rapidly than either the ability of the muscles to generate force, or the ability of the skeleton to support these loads. Here we demonstrate how one of the very largest sauropods, Argentinosaurus huinculensis (40 metres long, weighing 83 tonnes), may have moved. A musculoskeletal model was generated using data captured by laser scanning a mounted skeleton and assigning muscle properties based on comparative data from living animals. Locomotion is generated using forward dynamic simulation to calculate the accelerations produced by the muscle forces, coupled with machine learning technique to find a control pattern that minimises metabolic cost. The simulation demonstrates that at such vast body size, joint range of motion needs to be restricted to allow sufficient force generation for an achievable muscle mass. However when this is done, a perfectly plausible gait can be generated relatively easily. Whilst this model represents the best current simulation of the gait of these giant animals, it is likely that there are as yet unknown mechanical mechanisms, possibly based on passive elastic structures that should be incorporated to increase the efficiency of the animal9s locomotion. It is certainly the case that these would need to be incorporated into the model to properly assess the full locomotor capabilities of the animal.
Triassic Sauropterygian Keichousaurus hui Sexual Dimorphism Described
New information on sexual dimorphism and allometric growth in Keichousaurus hui, a pachypleurosaur from the Middle Triassic of Guizhou, South China
Authors:
Xue Yifan et al.
Abstract:
Keichousaurus hui is a small pachypleurosaur (Reptilia: Sauropterygia) from the Triassic of China. Many specimens of various growth stages are known, making it ideal for ontogenetic research. We report 22 new specimens from the Middle Triassic of Xingyi (Guizhou, south China), and combined their skeletal measurements with those from 85 published specimens to analyze the ontogenetic trajectory of sexual dimorphism. An Exploratory Factor Analysis suggests that the largest factors behind morphological disparity within the species are body size followed by gender. Sexual dimorphism is most clearly reflected in selected skeletal ratios that are more pronounced in males than in females. We found that the relative length of femur to body size was useful in gender identification, in addition to three ratios that are traditionally used, namely a distal expansion of the humerus relative to its shaft, humerus length relative to body size, and humerus length relative to femur length. Two distinctive patterns exist in allometric changes of these four ratios. The distal expansion of the humerus is exceptional in that it is equally pronounced in juvenile and adult males and therefore must have been fully established during embryonic growth. The other three features are not pronounced at birth size and subsequently become pronounced during postembryonic growth. However, males and females already show different growth trajectories at birth size even in these three. Therefore, the fate of sexually dimorphic features seems to have already been set during embryonic growth in K. hui.
A World Without Life is a World With Smaller Continents
Biotic vs. abiotic Earth: A model for mantle hydration and continental coverage
Authors:
Höning et al
Abstract:
The origin and evolution of life has undoubtedly had a major impact on the evolution of Earth's oceans and atmosphere. Recent studies have suggested that bioactivity may have had an even deeper impact and may have caused a change in the redox-state of the mantle and provided a path for the formation of continents. We here present a numerical model that assumes that bioactivity increases the continental weathering rate and that relates the sedimentation rate to the growth of continents and to the hydration of the mantle using elements of plate tectonics and mantle convection. The link between these factors is provided by assuming that an increase of the thickness of the sedimentary layer of low permeability on top of a subducting oceanic slab will reduce its dewatering upon subduction. This in turn leads to a greater availability of water in the source region of andesitic partial melt, resulting in an enhanced rate of continental crust production, and to an increased regassing rate of the mantle. The mantle in turn responds by reducing the mantle viscosity and increasing the convective circulation rate, degassing rate and plate speed. We use parameters that are observed for the present Earth and gauge uncertain parameters such that the present day continental surface area and mantle water concentration can be obtained. Our steady state results show two stable fixed points in a phase plane defined by the fractional continental surface area and the water concentration in the mantle, one of them pertaining to a wet mantle and the continental surface area of the present day Earth, and the other to a dry mantle and a small continental surface area. When the sedimentation rate is reduced, both fixed points move and the area of attraction of the latter fixed point increases systematically. We conclude that if the presence of life has increased the continental weathering rate, as is widely believed, and led to the observables of a wet mantle and a continental surface coverage of roughly 40%, an abiotic Earth would likely have evolved towards a dry mantle with a small continental surface area instead.
India is Pushing for a Larger Share of Joint Development of the Russian PAK-FA/T-50 Derived Fighter
India’s share in research-and-development work for the joint Fifth Generation Fighter Aircraft (FGFA) project with Russia is currently limited by India’s domestic industrial capabilities but will gradually increase with the project’s implementation, a Russian military expert said Friday.
India’s The Economic Times newspaper reported on October 17 that Indian military officials were concerned over the country’s work share in the FGFA project, which is currently only 15 percent even though New Delhi is bearing 50 percent of the cost.
According to the paper, India’s defense minister is expected to raise that issue during his visit to Russia beginning November 15.
“The figure cited by the Indian side reflects current capabilities of India’s industry, in particular the Hindustan Aeronautics Limited [HAL] corporation,” said Igor Korotchenko, head of the Moscow-based Center for Analysis of Global Arms Trade.
link.
Russian Threatens Reignite Gas Wars With Ukraine
Russian Prime Minister Dmitry Medvedev says Russia will ask Ukraine to start pre-paying for gas supplies in case Ukraine doesn't settle outstanding debts.
Medvedev's statement is the latest attempt to put pressure on Ukraine as it hopes to sign a landmark association agreement with the European Union next month, which would establish a free-trade zone and bolster political ties.
Russia has warned Ukraine that doing business between the two countries will be more difficult if Ukraine signs the deal.
link.
Tuesday, October 29, 2013
InfinitEye Prototype VR Display: a Road to VR Review
InfinitEye is a prototype head mounted display that uses dual 1280×800 displays to create a massive 210 degree field of view. I traveled to Toulouse, France to be the first journalist in the world to go hands-on with the unit. These are my thoughts on the trip, the team, and the HMD itself.
link.
US Navy Testing Anti-torpedo Missile
The Navy is gearing up for the deployment and a new round of tests of its Surface Ship Torpedo Defense System — a high tech system designed to protect aircraft carriers by locating, tracking and intercepting incoming torpedoes, Navy leaders said Oct. 24 at the Naval Submarine League, Falls Church, Va.
The upcoming tests, slated to take place on the USS George H.W. Bush, are designed as a follow on to initial end-to-end testing of an early prototype model aboard the Bush this past May. The Navy plans to equip all aircraft carriers with SSTD by 2035.
The SSTD system, which consists of a sensor, processor and small interceptor missile, is a first-of-its-kind “hard kill” countermeasure for ships and carriers designed to defeat torpedoes, said Rear Adm. Dave Johnson, Program Executive Officer, Submarines.
The SSTD is slated for additional testing on board the USS Bush later this month in what’s called a Quick Reaction Assessment, Johnson said. The SSTD will be an Engineering Development Model of the technology, meaning it will be further tweaked and refined before deploying aboard the USS Bush in the near future.
link.
Korea Aerospace Industries Pushes for Changes to KF-X Program
Korea Aerospace Industries (KAI) is pushing for South Korea to cut the technical challenges of its proposed KF-X fighter program, offering a single-engine concept that probably has a distant connection with the Lockheed Martin F-16. KAI's KFX-E design should be cheaper to develop and build than the larger proposals put forward by the Agency for Defense Development (ADD), the chief proponent of the KF-X.link.
Also much smaller than and more differentiated from the Lockheed Martin F-35, the KFX-E may offer the further advantage of minimizing competition from that U.S. stealth fighter. But it may have Lockheed Martin or other U.S. intellectual property in its design, exposing it to a foreign veto over sales or even development.
Seoul will probably have a foreign alternative to consider, too. Western proposals for KF-X include twin-tail developments of the F-16 and Eurofighter Typhoon, and an advanced version of the Boeing F/A-18E/F Super Hornet. Those offerings were included as technology transfer in bids for the separate F-X Phase 3 program for 60 fighters. F-X Phase 3 has been abandoned, but a successor competition will be needed, probably reviving foreign KF-X proposals.
KAI has moved from cooperation to competition with ADD. For a decade, the manufacturer was a design contractor in support of the agency. But industry officials say that at least some KAI executives have long regarded ADD's plan to develop a twin-engine Typhoon-size KF-X as too ambitious. Meanwhile, the South Korean government has repeatedly deferred launching the KF-X. If it goes ahead, it cannot enter service before the mid-2020s. Cutting costs by accepting a smaller size would probably improve the program's chances.
In July, KAI coyly published a picture of a stealthy KF-X concept related to its T-50 supersonic trainer and called KFX-E (or KF-X-E). It gave no details then and did not respond to Aviation Week's request for comment (AW&ST July 22, p. 33). But now the company has stepped up to make its case for the aircraft, arguing at an official seminar that the KFX-E would meet all air force requirements, except for being powered by just one engine.
The KFX-E turns out to be much larger than the T-50, with an empty weight of 9.3 metric tons. It is larger even than the 8.9-ton F-16, from which the T-50 is derived, but remains much smaller than ADD's two proposals, the C103 and C203, each about 11 tons empty (AW&ST April 29, p. 46).
KAI has worked out two versions of the KFX-E, one with a single fin and one with two, the latter presumably demanding more development work but reducing radar reflections. KAI has not provided for a weapons bay in the KFX-E; ADD has reserved space for a bay in its designs, though neither the C103 nor C203 would initially have one. Following a 2009 decision to downgrade the stealthiness of the KF-X, the ADD proposed first to field an aircraft whose shape would give it the makings of a low-observable fighter. Later versions would introduce features to realize that potential.
Attempt no Landings Here: Does Europa Have Penitentes Guarding its Equator?
A deadly bed of icy javelins could be awaiting any spacecraft that tries to land on some parts of the ice-covered world Europa, say researchers who have carefully modeled the ice processes at work on parts of the Jovian moon to detect features beyond the current low resolution images.
If the prediction of long vertical blades of ice is correct, it will not only help engineers design a lander to tame or avoid the sabers, but also help explain a couple of nagging mysteries about the strange moon.
Currently, the very best images of Europa only see 10 meters per pixel, at best, said Daniel Hobley of the University of Colorado. That means that if giant ice daggers do exist, they could still be several meters long and still escape detection.
To learn more, Hobley and his colleagues looked to Chile, where high in the mountains there are peculiar icy features called penitentes that are not found in polar regions.
"Penitentes are very, very sharp blades and spikes of ice," said Hobley. "They are famously well developed in Chile and only develop in the tropics on Earth."
The reason for the tropical location is that in order to sculpt the blade, the sun's rays must shine down almost vertically throughout the year so the light is always drilling down at the bottom of the crevices, between the blades, rather than the sides of the blades. In contrast, at higher latitudes the sun's angle changes dramatically through even a single season, so that light would shine on the sides of the blades and melt them before they had time to develop to any significant size.
The researchers also predict that penitentes, perhaps up to five meters long, could crowd Europa's surface in a wide band centered on the equator.
link.
Sensitivity of Biosignatures on Earth-like Planets orbiting in the Habitable Zone of Cool M-Dwarf Stars to varying Stellar UV Radiation and Surface Biomass Emissions
Authors:
Grenfell et al
Abstract:
We find that variations in the UV emissions of cool M-dwarf stars have a potentially large impact upon atmospheric biosignatures in simulations of Earth-like exoplanets i.e. planets with Earth's development, and biomass and a molecular nitrogen-oxygen dominated atmosphere. Starting with an assumed black-body stellar emission for an M7 class dwarf star, the stellar UV irradiation was increased stepwise and the resulting climate-photochemical response of the planetary atmosphere was calculated. Results suggest a “Goldilocks” effect with respect to the spectral detection of ozone. At weak UV levels, the ozone column was weak (due to weaker production from the Chapman mechanism) hence its spectral detection was challenging. At strong UV levels, ozone formation is stronger but its associated stratospheric heating leads to a weakening in temperature gradients between the stratosphere and troposphere, which results in weakened spectral bands. Also, increased UV levels can lead to enhanced abundances of hydrogen oxides which oppose the ozone formation effect. At intermediate UV (i.e. with x10 the stellar UV radiative flux of black body Planck curves corresponding to spectral class M7) the conditions are “just right” for spectral detection. Results suggest that the planetary O3 profile is sensitive to the UV output of the star from ∼(200–350) nm.We also investigated the effect of increasing the top-of-atmosphere incoming Lyman-α radiation but this had only a minimal effect on the biosignatures since it was efficiently absorbed in the uppermost planetary atmospheric layer, mainly by abundant methane. Earlier studies have suggested that the planetary methane is an important stratospheric heater which critically affects the vertical temperature gradient, hence the strength of spectral emission bands. We therefore varied methane and nitrous oxide biomass emissions, finding e.g. that a lowering in methane emissions by x100 compared with the Earth can influence temperature hence have a significant effect on biosignature spectral bands such as those of nitrous oxide. Our work emphasizes the need for future missions to characterize the UVof cool M-dwarf stars in order to understand potential biosignature signals.
Increased Understanding of the Orbits of Multi Exoplanet Systems
DISK-PLANETS INTERACTIONS AND THE DIVERSITY OF PERIOD RATIOS IN KEPLER'S MULTI-PLANETARY SYSTEMS
Authors:
Clement Baruteau and John C. B. Papaloizou
Abstract:
The Kepler mission is dramatically increasing the number of planets known in multi-planetary systems. Many adjacent planets have orbital period ratios near resonant values, with a tendency to be larger than required for exact first-order mean-motion resonances. This feature has been shown to be a natural outcome of orbital circularization of resonant planetary pairs due to star-planet tidal interactions. However, this feature holds in multi-planetary systems with periods longer than 10 days, in which tidal circularization is unlikely to provide efficient divergent evolution of the planets' orbits to explain these orbital period ratios. Gravitational interactions between planets and their parent protoplanetary disk may instead provide efficient divergent evolution. For a planet pair embedded in a disk, we show that interactions between a planet and the wake of its companion can reverse convergent migration and significantly increase the period ratio from a near-resonant value. Divergent evolution due to wake-planet interactions is particularly efficient when at least one of the planets opens a partial gap around its orbit. This mechanism could help account for the diversity of period ratios in Kepler's multiple systems from super-Earth to sub-Jovian planets with periods greater than about 10 days. Diversity is also expected for pairs of planets massive enough to merge their gap. The efficiency of wake-planet interactions is then much reduced, but convergent migration may stall with a variety of period ratios depending on the density structure in the common gap. This is illustrated for the Kepler-46 system, for which we reproduce the period ratio of Kepler-46b and c.
Paleoecology of Azhdarchid Pterosaurs: Giant Pelicans or Theropod Competitors
Apex predators from ecosystems containing giant azhdarchids to scale with a giant azhdarchid
species, A, the largest known tyrannosaurid, Tyrannosaurus rex from North America, contemporary
of Quetzalcoatlus northropi and other large azhdarchids; B, the small Haţeg dromaeosaur Balaur
bondoc, contemporary of Hatzegopteryx thambema;. C, the 10 m wingspan Arambourgiania
philadelphiae (note that H. thambema was proportionally more robust than Arambourgiania); D,
Homo sapiens, standing height of 1.83 m. {two column width}
Azhdarchid pterosaurs: water-trawling pelican mimics or "terrestrial stalkers"?
Authors:
Mark P. Witton and Darren Naish
Abstract:
The lifestyles of all pterosaurs are contentious, but those of the pterodactyloid clade Azhdarchidae are particularly debated. A 2008 review of the functional morphology of azhdarchid pterosaurs concluded that they were probably terrestrial foragers, as evidenced by their long limbs, generalised skull construction, the arthrological limitations of their cervical series, trackway data indicating terrestrial proficiency, a strong continental skew in the depositional context of their fossils, and several additional lines of corroborating evidence. This hypothesis was recently challenged on three counts: 1) azhdarchid fossils routinely occur in aquatic deposits; 2) terrestrially-foraging pterosaurs were highly vulnerable to predation and 3), aerial ‘water trawling’, where the mandible is pulled though water to catch food in a distended throat pouch, is a more likely foraging strategy. Pelican-like jaw mechanics were suggested for azhdarchids because of the asymmetrical jaw joints in these pterosaurs, which permit lateral deflection of the mandibular rami during jaw extension. We evaluate these three claims and conclude that all are flawed. The frequent occurrence of azhdarchid fossils in aquatic sedimentary systems is not significant with regard to ecology or behaviour, since these provide the overwhelming mechanism for the preservation of all fossil terrestrial animals. Likely pterosaur takeoff abilities and the ubiquitous nature of modern, terrestrially-foraging birds indicate that predation risks on ground-foraging pterosaurs are probably overstated. The kinematics of pterosaur jaws are entirely different to those of pelicans, which are highly specialised compared to those of all other tetrapods, and there are no indications from azhdarchid jaw anatomy that azhdarchids indulged in pelican-like foraging behaviour. The estimated amount of jaw expansion present in azhdarchids was minimal compared to that of pelicans, even when the asymmetrical jaw joints of azhdarchids are taken into account. Moreover, the widespread occurrence of asymmetrical jaw joints in other reptiles demonstrates that they are not related to any specific feeding habits. We conclude that terrestrial foraging remains the most parsimonious habit for azhdarchid pterosaurs.
Mark also has an awesome post up on his own blog on the paper.
Amber Isotope Ratios Give Much Lower Atmospheric Oxygen Levels Since Triassic Than Other Proxies
Stable carbon isotopes of C3 plant resins and ambers record changes in atmospheric oxygen since the Triassic
Authors:
Tappert et al.
Abstract:
Estimating the partial pressure of atmospheric oxygen (pO2) in the geological past has been challenging because of the lack of reliable proxies. Here we develop a technique to estimate paleo-pO2 using the stable carbon isotope composition (δ13C) of plant resins—including amber, copal, and resinite—from a wide range of localities and ages (Triassic to modern). Plant resins are particularly suitable as proxies because their highly cross-linked terpenoid structures allow the preservation of pristine δ13C signatures over geological timescales. The distribution of δ13C values of modern resins (n = 126) indicates that (a) resin-producing plant families generally have a similar fractionation behavior during resin biosynthesis, and (b) the fractionation observed in resins is similar to that of bulk plant matter. Resins exhibit a natural variability in δ13C of around 8‰ (δ13C range: −31‰ to −23‰, mean: −27‰), which is caused by local environmental and ecological factors (e.g., water availability, water composition, light exposure, temperature, nutrient availability). To minimize the effects of local conditions and to determine long-term changes in the δ13C of resins, we used mean δ13C values (View the MathML source) for each geological resin deposit. Fossil resins (n = 412) are generally enriched in 13C compared to their modern counterparts, with shifts in View the MathML source of up to 6‰. These isotopic shifts follow distinctive trends through time, which are unrelated to post-depositional processes including polymerization and diagenesis. The most enriched fossil resin samples, with a View the MathML source between −22‰ and −21‰, formed during the Triassic, the mid-Cretaceous, and the early Eocene. Experimental evidence and theoretical considerations suggest that neither change in pCO2 nor in the δ13C of atmospheric CO2 can account for the observed shifts in View the MathML source. The fractionation of 13C in resin-producing plants (Δ13C), instead, is primarily influenced by atmospheric pO2, with more fractionation occurring at higher pO2. The enriched View the MathML source values suggest that atmospheric pO2 during most of the Mesozoic and Cenozoic was considerably lower (pO2 = 10–20%) than today (pO2 = 21%). In addition, a correlation between the View the MathML source and the marine δ18O record implies that pO2, pCO2, and global temperatures were inversely linked, which suggests that intervals of low pO2 were generally accompanied by high pCO2 and elevated global temperatures. Intervals with the lowest inferred pO2, including the mid-Cretaceous and the early Eocene, were preceded by large-scale volcanism during the emplacement of large igneous provinces (LIPs). This suggests that the influx of mantle-derived volcanic CO2 triggered an initial phase of warming, which led to an increase in oxidative weathering, thereby further increasing greenhouse forcing. This process resulted in the rapid decline of atmospheric pO2 during the mid-Cretaceous and the early Eocene greenhouse periods. After the cessation in LIP volcanism and the decrease in oxidative weathering rates, atmospheric pO2 levels continuously increased over tens of millions of years, whereas CO2 levels and temperatures continuously declined. These findings suggest that atmospheric pO2 had a considerable impact on the evolution of the climate on Earth, and that the δ13C of fossil resins can be used as a novel tool to assess the changes of atmospheric compositions since the emergence of resin-producing plants in the Paleozoic.
New Data From Congo Carton Suggests Greenhouse Paleoclimate During Break up of Rodinia
Depositional age, provenance, and tectonic and paleoclimatic settings of the late Mesoproterozoic–middle Neoproterozoic Mbuji-Mayi Supergroup, Democratic Republic of Congo
Authors:
Delpomdor et al.
Abstract:
The late Mesoproterozoic–middle Neoproterozoic period (ca. 1300 Ma–800 Ma) heralded extraordinary climatic and biological changes related to the tectonic changes that resulted in the assembly (~ 1.0 Ga) and the break-up of Rodinia (880 Ma–850 Ma). In the Democratic Republic of Congo, these changes are recorded in the Mbuji-Mayi Supergroup which was deposited in the SE–NW trending siliciclastic-carbonate failed-rift Sankuru-Mbuji-Mayi-Lomami-Lovoy Basin. New LA-ICP–MS U–Pb laser ablation data on detrital zircon grains retrieved from the lower arenaceous-pelitic sequence (BI group) together with C and Sr isotopic data on carbonates from the upper dolomitic-pelitic sequence (BII group) and an 40Ar/39Ar age determination on a dolerite give a new depositional time frame between 1174 ± 22 Ma and ca. 800 Ma for the Mbuji-Mayi Supergroup. The upper age limit is based on the assumption that the transition between the BIIb and BIIc subgroups recorded the Bitter Springs anomaly. In terms of tectonic and paleoclimatic settings, the BII group was deposited in the eastern passive margin of the Congo Craton during warm periods interlaced with temporarily dry and wet seasons, suggesting greenhouse conditions during the fragmentation of Rodinia.
Chinese Pursuing its own E-2 Carrier Borne AWACS
China’s building a second aircraft carrier—a bigger, more capable flattop to take over from Liaoning, a refurbished Russian vessel that Beijing is using to learn naval aviation fundamentals.
And the new carrier could have a powerful new radar plane, thanks to China’s efforts to copy—and steal—details of the America’s own E-2 Hawkeye early-warning aircraft.
In late October, authorities in Taipei revealed that a major in the Taiwanese air force—part of a ring of up to 20 turncoats—had been caught trying to sell technical data on the E-2 to Chinese agents. Taiwan operates six of the twin-engine E-2s, which feature a large rotating radar dish atop their fuselages for detecting ships and airplanes hundreds of miles away.
Taiwan flies its Hawkeyes from land, but the U.S. and French navies use their own E-2s aboard aircraft carriers. The Northrop Grumman-built radar planes are among the most important aircraft on a flattop. Crewed by “battle managers,” they spot targets and help plot courses for jet fighters and other planes.
Rugged, compact and optimized for short takeoffs and landings, the E-2 is ideal for shipboard use. But it requires a catapult to boost it off a carrier’s deck. China’s rebuilt first flattop Liaoning does not have a catapult and therefore cannot operate large, heavy planes like the Hawkeye. But the second carrier, currently under construction, does have a catapult—if a few blurry photos are any indication.
link.
Monday, October 28, 2013
Sierra Nevada's DreamChaser Suffers Mishap From Failed Landing Gear, Causes DC to Flip
[Yesterday], Sierra Nevada Corporation (SNC) performed its first free-flight approach-and-landing test of the Dream Chaserspacecraft. The vehicle successfully released from its carrier aircraft, an Erickson Air-Crane helicopter, as planned at approximately 11:10 a.m. Pacific Standard [sic] Time. Following release, the Dream Chaser spacecraft automated flight control system gently steered the vehicle to its intended glide slope. The vehicle adhered to the design flight trajectory throughout the flight profile. Less than a minute later, Dream Chaser smoothly flared and touched down on Edwards Air Force Base’s Runway 22L right on centerline. While there was an anomaly with the left landing gear deployment, the high-quality flight and telemetry data throughout all phases of the approach-and-landing test will allow SNC teams to continue to refine their spacecraft design. SNC and NASA Dryden are currently reviewing the data.
link.
Northrop Grumman Playing Chess with Bomber Bid? Or Poker?
Northrop Grumman is not saying whether it will compete in the U.S. Air Force’s Long-Range Strike – Bomber program.link.
Boeing and Lockheed Martin have announced that they will be teaming up to pursue the contract, with Boeing as prime and Lockheed as chief teammate.
“Northrop Grumman views the Long-Range Strike Bomber program as vital to both national security and the power projection capability of the U.S. Air Force,” the company stated. “We do not comment on other companies’ business arrangements and have no further comment on the program at this time.”
The move is surprising, because Northrop has been publicly promoting its qualifications to build the Air Force’s next bomber for more than a decade, based on its experience with the B-2 program. The company continued that campaign through September’s Air Force Association show via advertising and the release of a specially commissioned book about the B-2’s history. But the defense manufacturer elected to no-bid the final stage of the USAF tanker program after investing many years and a great deal of money into its Airbus A330-based proposal.
Even a threat of a no-bid decision puts the Pentagon in an awkward position, because it would turn a program valued at well above $60 billion into a sole-source Boeing effort – which would likely draw widespread scrutiny and some outright opposition in Congress.
One observer notes that Northrop Grumman may be pressuring the Pentagon into more generous funding. The Pentagon is proposing a development program in which cost-reimbursable line items (that is, non-fixed-price) would be limited to areas where the government sees risk, while incentive payments will be tied to tangible deliverables rather than paper milestones. Senior Pentagon leadership expects to supervise a “should cost” process, controlling the release money to the program office.
Alternatively, Northrop Grumman may be looking to level the playing field if – as has been reported – Lockheed Martin is already building an LRS-B-related demonstrator. This would be a replay of the early history of stealth, where Northrop (in 1979) initially declined to bid on what became the B-2 until it was sure that the requirements would not favor Lockheed, which had already flown the Have Blue stealth prototype and was under contract for the F-117.
Total Carbon Input to Eocene Hyperthermal Might Have been 66% Higher Than Previously Thought
Recovering the true size of an Eocene hyperthermal from the marine sedimentary record
Authors:
Sandra Kirtland Turner and Andy Ridgwell
Abstract:
Hyperthermals − episodes of abrupt global warming associated with the massive injection of carbon into the oceans and atmosphere − represent possible analogs for future climate change. However, uncertainties in their magnitude, rate, and duration arising as a result of mixing processes and changes in carbonate preservation as the sediment record is formed, complicate their use in constraining climate sensitivity and the role of carbon cycle feedbacks. Here, we use cGENIE, an Earth system model of intermediate complexity, to assess likely magnitude and rate of carbon input, taking a small hyperthermal event from the early-middle Eocene, C22nH3 (~49.2 Ma) as a case study. We develop an iterative method combined with a sediment model simulating the formation and mixing of deep-sea sediments to converge on an estimate for the ‘true’ magnitude of the carbon cycle perturbation in the atmosphere and ocean that drives the event. In inverting the -0.95‰ benthic δ13C excursion recorded at ODP Site 1258 we obtain an estimate of at least -1.45‰ for the atmospheric CO2 δ13C excursion that drove event C22nH3. We also assess controls on inter-site variation of event shape in model sediments and find that sedimentation rate is the strongest determinant of modeled event size, with higher sedimentation rate sites recording the atmospheric signal more accurately. Our revised estimate for the size of C22nH3 implies a total carbon input almost two thirds higher than would be deduced if the recorded δ13C excursion magnitude was taken at face value.
Carbon Rich Terrestrial Worlds may be Water Poor, Lack Oceans
Planets rich in carbon, including so-called diamond planets, may lack oceans, according to NASA-funded theoretical research.link.
Our sun is a carbon-poor star, and as result, our planet Earth is made up largely of silicates, not carbon. Stars with much more carbon than the sun, on the other hand, are predicted to make planets chock full of carbon, and perhaps even layers of diamond.
By modeling the ingredients in these carbon-based planetary systems, the scientists determined they lack icy water reservoirs thought to supply planets with oceans.
"The building blocks that went into making our oceans are the icy asteroids and comets," said Torrence Johnson of NASA's Jet Propulsion Laboratory in Pasadena, Calif, who presented the results Oct. 7 at the American Astronomical Society Division of Planetary Sciences meeting in Denver. Johnson, a team member of several NASA planetary missions, including Galileo, Voyager and Cassini, has spent decades studying the planets in our own solar system.
"If we keep track of these building blocks, we find that planets around carbon-rich stars come up dry," he said.
Johnson and his colleagues say the extra carbon in developing star systems would snag the oxygen, preventing it from forming water.
"It's ironic that if carbon, the main element of life, becomes too abundant, it will steal away the oxygen that would have made water, the solvent essential to life as we know it," said Jonathan Lunine of Cornell University, Ithaca, N.Y., a collaborator on the research.
paper link.
hat tip to James.
HAT-P-13 system Exoplanets may be Apsidally Locked
SECULAR ORBITAL EVOLUTION OF COMPACT PLANET SYSTEMS
Authors:
Ke Zhang, Douglas P. Hamilton, and Soko Matsumura
Abstract:
Recent observations have shown that at least some close-in exoplanets maintain eccentric orbits despite tidal circularization timescales that are typically much shorter than stellar ages. We explore gravitational interactions with a more distant planetary companion as a possible cause of these unexpected non-zero eccentricities. For simplicity, we focus on the evolution of a planar two-planet system subject to slow eccentricity damping and provide an intuitive interpretation of the resulting long-term orbital evolution. We show that dissipation shifts the two normal eigenmode frequencies and eccentricity ratios of the standard secular theory slightly, and we confirm that each mode decays at its own rate. Tidal damping of the eccentricities drives orbits to transition relatively quickly between periods of pericenter circulation and libration, and the planetary system settles into a locked state in which the pericenters are nearly aligned or nearly anti-aligned. Once in the locked state, the eccentricities of the two orbits decrease very slowly because of tides rather than at the much more rapid single-planet rate, and thus eccentric orbits, even for close-in planets, can often survive much longer than the age of the system. Assuming that an observed close-in planet on an elliptical orbit is apsidally locked to a more distant, and perhaps unseen companion, we provide a constraint on the mass, semi-major axis, and eccentricity of the companion. We find that the observed two-planet system HAT-P-13 might be in just such an apsidally locked state, with parameters that obey our constraint reasonably well. We also survey close-in single planets, some with and some without an indication of an outer companion. None of the dozen systems that we investigate provides compelling evidence for unseen companions. Instead, we suspect that (1) orbits are in fact circular, (2) tidal damping rates are much slower than we have assumed, or (3) a recent event has excited these eccentricities. Our method should prove useful for interpreting the results of both current and future planet searches.
Dinosaur Cove Site in Albanian Cretaceous Australia Has Landing Trackways From Flying Birds
Two fossilized footprints found at Dinosaur Cove in Victoria, Australia, were likely made by birds during the Early Cretaceous, making them the oldest known bird tracks in Australia.
The journal Palaeontology is publishing an analysis of the footprints led by Anthony Martin, a paleontologist at Emory University in Atlanta who specializes in trace fossils, which include tracks, burrows and nests. The study was co-authored by Patricia Vickers-Rich and Michael Hall of Monash University in Victoria and Thomas Rich of the Museum Victoria in Melbourne.
Much of the rocky coastal strata of Dinosaur Cove in southern Victoria were formed in river valleys in a polar climate during the Early Cretaceous. A great rift valley formed as the ancient supercontinent Gondwana broke up and Australia separated from Antarctica.
"These tracks are evidence that we had sizeable, flying birds living alongside other kinds of dinosaurs on these polar, river floodplains, about 105 million years ago," Martin says.
The thin-toed tracks in fluvial sandstone were likely made by two individual birds that were about the size of a great egret or a small heron, Martin says. Rear-pointing toes helped distinguish the tracks as avian, as opposed to a third nearby fossil track that was discovered at the same time, made by a non-avian theropod.
A long drag mark on one of the two bird tracks particularly interested Martin.
"I immediately knew what it was – a flight landing track – because I've seen many similar tracks made by egrets and herons on the sandy beaches of Georgia," Martin says.
Martin often leads student field trips to Georgia's coast and barrier islands, where he studies modern-day tracks and other life traces, to help him better identify fossil traces.
The ancient landing track from Australia "has a beautiful skid mark from the back toe dragging in the sand, likely caused as the bird was flapping its wings and coming in for a soft landing," Martin says. Fossils of landing tracks are rare, he adds, and could add to our understanding of the evolution of flight.
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