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Comment Re:Martian Water (Score 4, Interesting) 97

I share your exasperation with the lack of popsci understanding of Mars' variable temperatures & pressures.

When I used to run planetarium shows for kids, I used to explain the temperature gradient by telling them, "If you stood on Mars, you'd wear sandals and a parka, since your feet would be as warm as a summer day but by the time you reached your head it'd be colder than winter in Antarctica!" which, although on the "tiny lies of oversimplification" side, is true-ish and a vivid enough image that they remembered months later.

Comment Terminiology & Reccommended Reading (Score 3, Informative) 97

I love that "above some critical threshold" is listed like a mysterious or complex thing. It's the angle of repose, the angle that a material naturally sits at when you let it fall from a height and pile up. It might be, if things are very complicated, the angle of repose + cohesion, but then you're back at water-based theories again since water is the easiest way to remove cohesion and trigger failure.

I also really like that the experimenters managed to recreate a sand flow in their lab. Of course they did. The field of prior research involving laboratory sand flows is immense, especially if you start including the ones with tiny glass beads of carefully varied diameters instead of sand. The only problem is thioxtropy -- landslides are renowned for having material that exhibit viscosity inversely proportional to velocity -- which is not easily replicable in small-scale lab settings.

I'm not sure if this is a, "Physicists discover what geologists already knew" moment, or a "Journalists are puzzled by the mundane mysteries of science," or what, exactly, but if you want to learn more about landslides on Mars, check out geotechnical journals starting with Lucchitta 1978 (Bulletin of the Geological Society of America, v89, pg 1601) and work your way forward. As the lunar and Martian landslides discredited an entire set of excess mobility theories, they're very well described and discussed.

Comment Re:Email Ad Agencies - They May Be Intrigued. (Score 1) 351

As far as detecting tsunamis from space, while not what the article poster is suggesting, would be a better use of orbiting lasers - detection of small rise in sea-level over a large area would, presumably, be a phenomena easily spotted from space.

...although more sensible than the article's idea, this one also won't work. The ocean isn't anywhere close to smooth -- follow the links on the difficulties of calibrating satellites from this 2007 article for an intro, then look up info on calculating the geoid -- and tsunamis are very, very small in open ocean.

But that's alright, since the science on predicting where the waves will go and when they'll arrive is incredibly good. The science on how big they'll be when they get there... now, that's an interesting problem worthy of more research & innovation!

Comment Notification Systems (Score 1) 351

If you want to take the parent's suggestion of studying this stuff seriously, some pointers:
- Check out U of Colorado's Natural Hazards Center. They have info on the major disaster research mailing lists, and put out a very good bulletin on the latest and greatest of ideas.
- A tsunami notification system (via email or SMS) already exists; it has the same inherent flaws as any other automated tsunami warning in that it only activates for earthquakes (not landslides) and lacks in expert judgment on if an event is likely to occur.

As for the easiest, cheapest, and most effective means of reducing tsunami danger: let the mangroves regrow. Mangroves act as an absorbing buffer; the areas with the least destruction and deaths from the Boxing Day Tsunami were all where the mangroves were intact. Tourist destinations tend to pluck the mangroves (huge beaches are so much more attractive for hotels), removing that protection. For the ugliest enactment of this risk-increasing policy, check out the mudflats of Cairns, Australia.

Comment Geomorphic stability (Score 3, Informative) 235

Just a pedantic little thing -- as a geomorphology instructor, I can tell you that rivers and coastlines are very, very likely to have changed. Check out pretty much any river mouth in Victoria, Australia, or any island off Maine, US in google earth vs google maps satellite mode for examples of how much they can change inside of just a few years. If something catastrophic has happened (big storm, big earthquake...), huge changes can shift the coastline inside of hours.

If you're going to use geomorphic features for your geocoding, find out what's most stable in your region (keyword search academic journals for geomorphology + your location + change and see what doesn't pop up, or ask a local university geo prof). Vegetated topography can be pretty stable over decades, especially if you only need relative shapes.

Comment Who ya gonna call? A Geologist (Score 1) 192

The geotechnical/geological engineers have also been treating soils as fluids for years -- check out any papers by Oldrich Hungr or Stephen Evans on landslides. Neil Balmforth, a geologist/mathematician, has piles of papers on fluid dynamics of small grains (sands or glass beads).

As a physicist working in earth science, yes, it is really nice to finally have some more solid reasons behind treating soft soils as fluids besides "because it works," but I disagree with the summary's claim that the discovery will lead to a whole new approach to soil sciences since it's already been treated as true for ages.

Submission + - NASA names space station treadmill after Colbert (sfgate.com)

willith writes: "Looks like the SF Chronicle is jumping the gun by an hour or so, but they've got an AP article up detailing the results of the International Space Station Node 3 naming contest (previously on Slashdot). Comedian and fake-pundit Stephen Colbert conducted a bombastic write-in campaign and repeatedly urged his show's fan base (the "Colbert Nation") to stuff the ballot box with his name, which resulted in "Colbert" coming in first in the write-in contest with almost a quarter-million votes. Although the Node 3 component will not be named "Colbert"--NASA has instead chosen to call it "Tranquility"--one of the Node 3 components will bear the honor: the second ISS treadmill, which will be installed in Node 3, will be named the Combined Operational Load Bearing External Resistance Treadmill. The formal announcement will be made on air tonight at 22:30 EDT on the Colbert Report on Comedy Central by astronaut Sunita Williams."

Submission + - Best of the Earth Observatory (nasa.gov)

SpaceMika writes: To celebrate the 10th anniversary of NASA's Earth Observatory, readers are voting on the most beautiful, most fascinating, or most unusual images from the Image of the Day collection. In the tradition of Apollo's "earthrise," do any of the images resonate as cultural icons? Browse now for the 50 best photos, or check back on 29 April for the winner.
United States

Submission + - Study Says People Don't Understand Rain Forecasts 1

Hugh Pickens writes: "Cognitive Psychologist Susan Joslyn writes that many people don't understand what the 20 percent chance of rain actually refers to. Many people think it means that it will rain over 20 percent of the area covered by the forecast or for 20 percent of the time period covered by the forecast. "When a forecast says there is 20 percent chance of rain tomorrow it actually means it will rain on 20 percent of the days with exactly the same atmospheric conditions," Joslyn says. To probe people's understanding of the term probability of precipitation, a technique used in public forecasts since the late 1960s, Joslyn and her colleagues tested more than 450 Pacific Northwest college students. Each student only saw one icon or "precipicons," that is visual representation of the chance of rain and forecast, and filled out a questionnaire. Two of the questions asked how much of the time it would rain and over approximately what area of the region would it likely rain today. The correct answer for both questions was "can't tell from this forecast," and only 43 percent of the students correctly responded to both questions. Joslyn says that if the misunderstandings uncovered in this research exist among a college-educated group of students from the Pacific Northwest, where it frequently rains, then similar error probably occur in similar, or larger, numbers elsewhere among the general public. "In dealing with a forecast about rain people must simultaneously consider several hypothetical outcomes, their corresponding levels of uncertainty and their consequences. For some people it may be easier to commit to a single outcome, reducing cognitive load, and proceed as through the uncertainty has been resolved. In some cases they may not be aware of this simplification.""

Comment Re:It would have likely occurred anyway (Score 1) 193

Exactly! It's in the key words: "cause" is the underlaying geology/structures/faults/etc that made it possible for this chunk to fail, "trigger" is why it happened at this particular time. If a trigger didn't happen (the dam wasn't built), then something else would act as a trigger later. Yes, the exact nature of the outcome would be different due to the intensity & distribution of the triggering event and other complex interactions blah blah blah, but it still would've been an earthquake. One of the big landslide bloggers posted an informal response to the academic article the news stories are based on. I thought his point about an artificially-triggered earthquake having liability consequences was interesting. I don't know the stats on death & damage for this event, but it'd certainly be enough to bankrupt anyone who was found fully or partially responsible for the disasters. I can see the usual suspects of conspiracy-theorists calling foul if the dam-triggering-earthquake theory is rejected by other scientists. After all, it wouldn't have anything to do with evaluating theories based on observations; the scientists would be protecting the geological engineers/regional planners/etc from bankruptcy, right? ;)

Researchers Discover How To Make the Perfect Phone Call Screenshot-sm 85

Having made amazing discoveries such as how to make the perfect cheese sandwich, linking heavy caffeine use to sleeplessness, and figuring out where all the teaspoons have gone, science has made the greatest breakthrough yet. They have uncovered the secrets of making the perfect phone call. The perfect phone call clocks in at a mere 9 minutes and 36 seconds, easily 11 minutes shorter than any conversation I've ever had with my mom. Unlike a call to mom, the perfect phone call is almost devoid of any gossip about her divorced neighbor and her heavily tattooed daughter. Instead three minutes should be spent catching up with news about family and friends, one minute on personal problems, a minute on work/school, 42 seconds on current affairs, 24 seconds on the weather, and 24 seconds talking about the opposite sex. What's left of your 9 mins 36 secs is a free for all.

Cisco Demos Public Rooms For Telepresence 65

CWmike writes "Matt Hamblen reports that Cisco Systems Inc. has announced the first telepresence videoconferencing rooms available for public use. It demonstrated the technology simultaneously in four locations in India, the US and the UK Three of the four demonstration sites were retrofitted rooms in Taj Hotels in London, Bangalore, India and Boston. The luxury hotel chain will build the videoconferencing rooms for business and guest use at rates starting at $400 an hour in the Boston location. Cisco said prices will vary from $299 to $899 an hour at various locations globally, depending on the number of users. The rooms can accommodate from one to 18 people."

Comment Detecting Exoplanets (Score 5, Informative) 142

There are two ways of detecting exoplanets:
1. Wobbles -- what you explained: watch a star for deviations in its orbit by observing tiny redshifts and blueshifts. Our own sun does a little jiggle thanks mostly to Jupiter.
2. Dimness -- what they did for this object. Watch a star for dimming as something passes in front of it, although you have to be careful of other causes of temporary decreases in luminescence (like sunspots).

In both cases, it really needs repeated observations over time to establish that it's an orbital event and not something random. In the good ol' days of exoplanet discovery when the equipment wasn't so hot & we expected to find planets pretty much like ours, it took a whole lot of observations before anyone was willing to take the risk of announcing a discovery. Now, with better equipment making it easier to detect hiccups in a star's routine and a more open attitude about how planets behave, discoveries are being announced a lot earlier in the observation process.

To be fair, TFA does give itself a whole lot of wiggle room in interpreting the data. It just fails to mention that follow-up observations aren't confirming the orbital parameters of the assumed planet.

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