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Gravity satellites could provide warning months ahead of floods

Flooding along the Missouri River on the Iowa-Nebraska border in 2011.

When the twin GRACE satellites were launched in 2002, the casual observer might have been underwhelmed by their mission—to make precise measurements of Earth's gravity. They've proved, however, to be unbelievably useful Swiss Army knives of geoscience, measuring everything from the loss of ice from Greenland and Antarctica to groundwater depletion in California. Now, the GRACE that keeps on giving has been shown to improve warnings ahead of major floods in some areas.

For many, floods seem to show up suddenly and then overstay their welcome. In some situations, they can be incredibly damaging and often quite dangerous. But a lot more goes into determining the size of a flood than just the amount of rain that falls, and that data provides the key to better forecasting of flood risk.

When looking at graphs of streamflow—the volume of water traveling downstream per second—for a river or stream, hydrologists can identify two kinds of behavior. There's the consistent base flow, supplied mainly by groundwater entering the river, and the temporarily higher flow that follows rain storms.

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Air force sends secret specs for new bomber to same old contractors

The B-2 Spirit was so expensive that its production run was cut. Now the Air Force is looking for a new bomber that will come in at a quarter of the B-2's pricetag.
US Air Force

The US Air Force has kicked off the competition that will determine who will build the Long Range Strike Bomber (LRS-B), a next-generation aircraft intended to replace the venerable B-52 bomber and the B-2 Spirit stealth bomber. This week, the Air Force sent requirements to industry for the program. Its goal is picking a winning design by spring of 2015.

The requirements were largely classified, but the mission isn't very secret. The Air Force has been driving the development of a new bomber around the mission of defending against the Chinese navy, based on a demonstration in 2004 that echoed Gen. Billy Mitchell's demonstration of the superiority of air power in 1921.

The 2004 bombing and sinking of the ex-USS Schenectady by a B-52, using laser-guided ordnance, after it was deliberately set adrift off Hawaii. The ship was found and targeted using sensors aboard the bomber, demonstrating how long-range bombers could be used in maritime strike.

Just like the Army and Marine Corps planes' sinking of the "unsinkable" German battleship Ostfriesland was intended to demonstrate the vulnerability of ships to bomber planes—and to shore up the budget for the then-shrinking Army Air Corps—the location and bombing of the former USS Schenectady off Hawaii was intended to demonstrate the role the Air Force could play in defending the Pacific against the growing threat of Chinese naval power. The role could include launching from bases out of range from China's "carrier-killer" anti-ship ballistic missiles and other long-range tactical weapons. The Air Force has been pushing for a plane built for that type of mission ever since, desiring a bomber capable of evading detection by the Chinese and striking at targets at sea.

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Thursday Dealmaster saves you $400 on a 2-pack of Monster Headphones

Greetings, Arsians! Our partners at LogicBuy are back with a pile of new deals this week. Do you like music? Do you have a friend who also likes music? Well then listen up, because this week's top deal is for both of you. $599 gets you two pairs of noise canceling headphones from Monster and a $300 Amazon gift card. If you count the $300 in Amazon money against the cost of the headphones, they're costing you about $150 each!

Featured deal
Monster Inspiration Active Noise Canceling Over-Ear Headphones (2-Pack) + $300 Amazon Gift Card for $599 with free shipping (list price $999)

Laptops and desktops

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Nadella to Microsoft: “Devices and services” out, but still “mobile first, cloud first”

E-mail sent—yes!
Microsoft

Microsoft CEO Satya Nadella sent a company-wide (and public) e-mail to mark the start of the company's 2015 financial year. The message announces a forthcoming reorganization and a shift in focus away from the "devices and services" that Steve Ballmer pushed toward the end of his time at the company.

It's not entirely clear what that new focus really is, however. Nadella isn't doing away with his "mobile first, cloud first" mantra, as mathematically challenged as it is, and "mobile first, cloud first" still seems to feel a lot like "devices and services." The lynchpin of the mobile experience is the device; the raison d'être of the cloud is to provide services.

The e-mail reinforces some themes that we've already seen from the company in past months. Nadella says that Microsoft's apps will be "built for other ecosystems," a policy that's already extant with apps including OneDrive, Skype, and most recently, Office. The parallel positioning of Visual Studio as an environment that's increasingly suitable for cross platform development lines up neatly with this.

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Amazon lets kids run amok with in-app purchases, says FTC suit

The Federal Trade Commission has filed a lawsuit against Amazon over its allowance of allegedly unauthorized in-app purchases charged by children to their parents' accounts, according to a press release Thursday. Kids could charge their parents up to $99.99 per in-app purchase, often without needing a password, writes the FTC, and Amazon's system has been lacking in controls since it was introduced in November 2011.

As Ars pointed out in December 2011, Amazon has long had parental controls for in-app purchases in its Kindle Fire OS. However, in its early days, the parental controls were off by default, and in-app purchases were allowed by default.

The FTC writes that Amazon updated its policy in March 2012 to require a password only for in-app purchases over $20. Amazon updated the process yet again in March 2013. Now, authorizing with a password opens an undisclosed 15-minute window when any attempted in-app charges will go through.

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Two of the exoplanets closest to Earth don’t actually exist

The Gliese 581 system, as it looked before the recent paper.

Two exoplanets, once considered excellent candidates in the search for life elsewhere in the Universe, do not exist, according to a new study in the journal Science. Both non-planets, Gliese 581d and 581g, were thought to be part of the Gliese 581 star system, located only 20 light-years away.

To those familiar with the history of the Gliese 581 system, the news comes as little surprise. Claims have been repeatedly made regarding the likelihood of habitability for some planet in the system, only to see that likelihood vanish upon closer scrutiny.

Excitement about Gliese 581 first peaked in 2007 when planet c was discovered. As one of the first exoplanets found in its star's habitable zone (the region around a star where the temperature is 'just right' for liquid water to exist), planet c seemed a good candidate for life. So good that, in 2008, a high-powered digital radio signal, dubbed "A Message From Earth," was sent in the direction of planet c. (It will arrive there in 2029, and, if anyone's there to respond, we can expect a reply 20 years after that).

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Parking spot auction app caves under pressure, halts in San Francisco

MonkeyParking, the Italian startup that allows iPhone users to auction off public parking spaces via its smartphone app, announced that it is temporarily suspending operations in San Francisco.

The move comes just one day before the San Francisco City Attorney's Office said it would sue the firm if it did not stop its activities in the city. Last month, the city sent the firm a cease-and-desist letter informing the company that what it was doing violated local law.

The company insisted that what it was doing was legal and that it would not shut down. But in a statement Thursday, MonkeyParking said it was altering course.

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FCC Republican says net neutrality rules too “onerous” for ISPs

You don't say.

FCC Commissioner Michael O'Rielly today blasted the commission's net neutrality proposal, calling it too "onerous" for Internet service providers and saying there should be no net neutrality rules until "there's evidence of an actual problem it would address."

O'Rielly, one of two Republicans on the five-member FCC, co-wrote an op-ed in National Review with US Rep. Marsha Blackburn (R-TN). In it, they discussed the rules the FCC voted in favor of in May. This proposal was also widely panned by net neutrality advocates because even though it would prevent ISPs from blocking content, it would also allow them to charge third-party Web services for a faster path to consumers, or a "fast lane." FCC Chairman Tom Wheeler said his rules would prevent ISPs from degrading the traffic of Web services that don't pay fast lane tolls, but opponents say that creating a faster path for those that do pay is essentially the same thing.

O'Rielly thinks the FCC erred by issuing rules at all. "In its most recent Notice of Proposed Rulemaking on net neutrality, the FCC shirked its responsibility again. The commission's woefully inadequate 'analysis' started with an unfounded assumption that the rules would be beneficial, then proposed several pages of onerous requirements, and concluded with one meager paragraph seeking comment on how to minimize the unquantified burdens," Blackburn and O'Rielly wrote. "Seeking comment on burdens is no substitute for performing an actual cost-benefit analysis, and doing so as an afterthought shows a disregard for the president's directives."

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Recently revived ISEE-3 probe can’t fire engines, can’t change orbit

NASA

Not every space story can have a Hollywood ending, and unfortunately it's looking like the situation with the newly resurrected ISEE-3 space probe is going to have a bittersweet conclusion. The International Sun-Earth Explorer 3 satellite has been dormant since 1998, but a crowdfunded group of "citizen scientists" were given permission by NASA to assume control of the spacecraft and see about bringing it into a closer orbit. The group, called the ISEE-3 Reboot Project, has been posting periodic updates on its blog, but the latest news isn't good at all—ISEE-3's thrusters aren't operating as expected.

The probe uses small monopropellant rockets for attitude and translation (i.e., turning and moving); these thrusters work by squirting some amount of toxic hydrazine fuel into a thrust chamber coated with a catalyst. The hydrazine reacts very energetically with the catalyst, and the resulting puff of gas is directed out of a thrust nozzle, turning or moving the craft. The catch—and this is a catch for any engine—is that you need a way to move the fuel from its tank into the engine. For most rocket engines intended to operate in microgravity and vacuum, the simplest way to do this is not with complex pumps but rather by pressurizing the fuel tank with some amount of non-reactive gas (nitrogen is the most common). When you need to fire the engine, you squeeze fuel out of the tanks by pushing in more nitrogen.

It appears that ISEE-3's nitrogen reserves have either been depleted or have leaked away into the void. Although the spacecraft was able to act on some of the commands sent to it during a spin-up on July 3 and a Trajectory Correction Maneuver on July 8, the ISEE-3 Reboot Project scientists suspect that the spacecraft's initial movement was the result of residual pressurized fuel in the propulsion system. The team has been performing remote troubleshooting on the craft and they believe they have eliminated malfunctioning valves and other hardware issues as a source of failure (and you thought fixing your parents' e-mail over the phone was hard!).

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