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On Thursday, the Solar Energy Industries Association (SEIA) published a quarterly report that offered surprising results. Despite a 30-percent tariff on solar cells and modules imported to the US, solar installations only fell by about nine percent, year over year.
At the same time, during the first half of 2018, utilities signed more than 8.5 gigawatts' worth of procurement deals for projects that will be completed before 2020. The effect is that US solar installment growth in 2018 and 2019 will likely remain flat year over year compared to 2017. That's better than most analysts expected.
There are a few reasons that President Trump's tariffs haven't had as much of an effect as they could have. According to Abigail Ross Hopper, SEIA's president and CEO, "the solar industry is simply too strong to be kept down." That's perhaps an overly rosy way of looking at it. The report itself notes that a lot of this growth comes from the fact that the US offers a 30-percent investment tax credit on solar installations that are completed before 2020. Tariffs or no, companies wanting to build panels stand to save a significant amount of money if they start building before the end of 2019 and snag that tax credit.
Half-siblings conceived with donated sperm and eggs are connecting online using DNA testing and online registries, forming extraordinarily large genetic families with dozens to hundreds of children linked to one parent, The Washington Post reports.
The modern family ties and genetic sleuthing are making it easier for donor-conceived children to learn about their backgrounds—and harder for anonymous donors to maintain anonymity. That has clearly been proven in tragic cases in which fertility doctors misled patients about their donor’s identity, even using their own sperm to sire dozens of children. But in legal, less-scandalous cases, the online connections are also highlighting the complex consequences of America’s lax regulations of the fertility industry, particularly on sperm and egg donations.
Many other countries have set legal limits on the number of children, families, or pregnancies to which one donor can contribute. Sperm donors in Taiwan can only sire one child, for instance. In Britain, they can donate to 10 families, and in China they can provide starter material for five pregnancies. But in the US, no such limits exist.
In the last few years, teams of scientists have developed a consistent protocol for rapidly analyzing the influence of climate change on extreme weather events. Within a week of the disaster, reports have been available to inform the conversation about whether we can expect more events like it in the future.
But on Wednesday, we saw the first example of something new—an analysis published before the event even happened. A group led by Stony Brook University’s Kevin Reed ran a very simple computer model experiment on Hurricane Florence—which isn’t due to make landfall until Friday—and quickly released the top-line results.
The rapid studies we’ve been seeing are done by examining the historical weather record to estimate how rare and extreme a given storm or heat event would be in that area of the globe. From there, climate model simulations are used to see if climate change is expected to change the frequency of that type of event.
Flying insects like bees, dragonflies, and fruit flies can perform impressive aerodynamic feats, particularly when seeking to evade predators or the swatting motion of a human hand. Now Dutch scientists have built a flying robot capable of executing similar maneuvers—despite being much larger than the average insects—that could shed light on how these creatures achieve those feats. The scientists described their work in a new paper in Science.
There was a time when scientists believed that insect wings worked a lot like airplane wings. The up and down motion of their wings would generate lift because air flowing over the wing follows its slightly tilted surface, while the downward flow lowers the air pressure above the wing, lifting it just enough to keep the body aloft. (This is a simplified, and therefore incomplete, explanation for the complicated aerodynamics of airplane lift based on Bernoulli's principle, but it will suffice for the purposes of this post.) But in the 1990s, a zoologist named Charles Ellington decided to test this theory by putting various insects in actual wind tunnels. The conventional lift they measured simply wasn't sufficient to account for their ability to fly.
Ellington's subsequent research showed that a stable leading-edge vortex is the most likely explanation for how insects stay aloft. Once the vortex forms, it spirals out along the wing toward the tip, drawing air outward so as to avoid a stall. That explains how insects generate lift to hover, but not how they manage to execute complicated maneuvers like making rapid banked turns. That's possibly due to how an insect wing can rotate to slightly get rid of the vortex for an extra bit of lift, enabling the insect to change direction. But there is still plenty of mystery remaining for scientists to explore. And that's where this new flying robot comes in.
The success of Tokamaks for fusion is a story unto itself, with the toroidal magnetic containers setting records for keeping high-energy plasmas under control, a necessary step for sustaining fusion. The overriding narrative, at least on the scientific side, is that when you have an unstable plasma, it is really hard to build a control system that keeps the plasma hot and confined, even in a Tokamak.
Now, researchers have used the Korean KSTAR Tokamak to show that they can gain control of a particularly nasty plasma instability called an edge localized mode. The instability essentially exhausts the plasma onto the wall, ablating it away. If a plasma reactor the size of ITER were to have an edge localized mode instability, it would likely destroy the inner lining of the vacuum vessel.Symmetries giveth, symmetries taketh
I don’t pretend to understand plasma instabilities in a Tokamak very well. But I do know that some of the problems are the result of the shape of the magnetic field. The shape of the Tokamak is a boon: it's symmetric, which makes the device simple, it makes calculations possible, and it offers high confinement.
Ten years ago today, Hurricane Ike made landfall as "only" a Category 2 hurricane along Galveston Island near Houston. Though Ike had 110mph winds at landfall, it had grown very large over the Gulf of Mexico, and this large size allowed it to develop an enormous amount of "integrated energy" that manifested itself as a devastating storm surge. With about $30 billion in damages, Hurricane Ike was, at the time, the second-costliest U.S. hurricane on record.
As of Thursday morning, Hurricane Florence has weakened to 110 mph as it contends with slightly increased wind shear and drier air. Technically this means Florence is no longer a "major" hurricane, and may not be when it reaches the North Carolina coast early on Friday morning. Practically, however, that won't matter when it comes to storm surge and inland rainfall.Storm surge
The simplest, most common metric for the measurement of a storm's intensity is maximum wind speed, and certainly this matters in terms of pure destructive potential when it comes to, say, losing a roof or propelling debris through the air. But when it comes to water, the maximum wind speed matters less than the size of the wind field for both storm surge and the destructive power of waves moving onshore. And Florence is a large storm, with hurricane-force winds extending outward up to 80 miles from the center and tropical-storm-force winds outward up to 195 miles.
The world’s oldest drawing might be easy for a casual observer to miss: a 38.6mm (1.52 inch) long flake of silcrete (a fine-grained cement of sand and gravel) with a few faint reddish lines drawn on one smooth, curved face using an iron-rich pigment called ocher. The lines would have been bolder and brighter when the drawing was new, according to University of Bergen archaeologist Christopher Henshilwood and his colleagues, but over time they’ve lost pigment to rinsing and wear, leaving them faint and patchy. But an archaeologist working at Blombos Cave, about 300km (186 miles) east of Cape Town, South Africa, noticed the markings while analyzing stone flakes and debris excavated from a 73,000-year-old layer of the site.
The design features six nearly parallel lines, with three curved lines cutting across them at an oblique angle, but it hints at a more complex piece of work. All the lines cut off abruptly at the edges of the flake, which suggests that the pattern archaeologists see today is just a fragment of something originally drawn on a larger surface and later broken.
“The pattern was probably more complex and structured in its entirety than in this truncated form,” wrote Henshilwood and his colleague. Modern viewers will likely never know what the rest of the drawing looked like—or what it meant to people 73,000 years ago.
As you may recall, a low-pressure leak occurred aboard the International Space Station in late August. Eventually the crews traced the leak to the orbital module of a Russian Soyuz spacecraft that had arrived at the station in June. After the problem was traced to what appears to be a manufacturing defect, the head of Russia's space program essentially called for the head of whoever made the error.
Now, however, something entirely new is afoot in Russia. A growing number of Russian publications have been putting forth an absurd new theory—that a NASA astronaut deliberately caused the leak on board the station in order to force the evacuation of a sick crew member. The story has spread like wildfire during the last 24 hours, according to Robinson Mitchell, who translates Russian space stories for Ars.
One of the most prominent articles was published Wednesday in Kommersant, which says Russian investigators are vigorously pursuing the claim that Americans may have damaged the Soyuz deliberately. Publicly, Roscosmos leader Dmitry Rogozin was quoted as saying about Russia's investigation into the leak, “Results we have received do not give us an objective picture. The situation is much more complex than we earlier thought.”