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Comment Blue crabs grow bigger shells, mud crabs eat less (Score 5, Informative) 203

Not sure why the link goes to the second page of the article, but on the first page they explain that blue crabs grow their shells faster in water with more carbon. (They note that bigger shells doesn't translate to more meat.) On the second page, they talk about the fact that mud crabs seem confused in water polluted with carbon, and that some mud crabs only ate half as much as in water with less carbon. Relevant quotes from the article:

Higher levels of carbon in the ocean are causing oysters to grow slower, and their predators — such as blue crabs — to grow faster

versus

Under conditions with lower levels of carbon, two mud crabs polished off 20 oysters in six hours. But in the aquariums with higher levels of carbon, the mud crabs seemed confused. They went over to the oysters, but they didn’t eat as many — sometimes fewer than half of what other crabs ate under normal conditions.

Comment Re:Newton (Score 2) 237

Voyager has no need for power to continue its journey; running out of power will have no effect on its velocity.

You're forgetting drag. Just like flying through air, flying through parts of the solar system results in drag from dust. The dust density is expected to increase when the probe reaches the inner Oort cloud, unless Voyager 1's path has angled enough above the ecliptic that it manages to miss it (I thought 35 degrees was high enough, my colleague disagrees.) If dust density increases, the drag will provide a small but continuous slowing effect. Once past the inner Oort cloud dust density will likely decrease, though no one I've worked with has a great guess of the dust density in the outer Oort cloud. It will still be non-zero though, and Voyager can't avoid the outer Oort. Added to the small but still present force of gravity from the sun (which is what keeps the Oort objects from drifting away), you have continuous drag on the craft.

We can't calculate the effect of that drag without knowing the dust density, and our estimates of the size of the Oort clouds are still rough (on the order of +-100AU last paper I read), which is why that NASA paper estimated crossing the outer edge of the Oort cloud in a range from 14K to 28K years. 14K if the Oort cloud is small and fairly dust-free, twice that long if our worst-case estimates of the density and size are correct.

Comment Re:Must be Wednesday (Score 2) 237

the linked stories don't mention how big a change in radiation was experienced. Are we talking 10%, or a factor of 10?

Yes they did, from TFA:

"Anomalous cosmic rays, which are cosmic rays trapped in the outer heliosphere, all but vanished, dropping to less than 1 percent of previous amounts."

and also

"galactic cosmic rays – cosmic radiation from outside of the solar system – spiked to levels not seen since Voyager's launch, with intensities as much as twice previous levels"

Comment Re:Isometric exercise (Score 1) 635

Along the same theme:
  • * Ankle weights. Since you're at a standing desk, put weights on your ankles. It added a surprising amount of extra work for my legs, moving that weight when I shifted my feet around.
  • * Sit on a fitness/yoga ball. I got tired standing so long, and my feet got sore. So I followed my co-workers' advice and alternated standing with sitting on a yoga ball. It takes the stress off your feet and legs for a bit, and really works your core (abs). Plus, it improved my posture (until I figured out a bizarre way to slouch while on a yoga ball.
  • * Electronic muscle stimulator. It's basically isometric exercises, but you don't have to think about doing them - turn on the device and it forces your muscles to flex at specific rates. I hated the feeling of being out of control, but my brother has been talking up his for years.

Comment Re:Like most overgeneralizations... (Score 1) 185

If your pages are not connected via links to any extern sites, then by definitionem, they are not part of the World Wide Web.

Do search engines count? Two of my sites are only linked from Google - a Google search for "link:sitename.com" yields no results, but Googling "sitename", "sitename.com" or some of the other variations returns all the pages. So they are reachable by people who know about them, and also to people who don't know the URL or IP address but know what to search for, but the site fail the "19 clicks" test unless someone has linked to a Google search that returns this site in the results. (Hasn't happened as far as I can tell.)

Security

Submission + - Company offers scholarship to Dawson student who exposed security flaws (www.cbc.ca)

Walking The Walk writes: The Dawson College computer science student who was expelled after discovering a security breach in a system used by students across Quebec has been offered a scholarship by the company behind the software.

"We will offer him a scholarship so he can finish his diploma in the private sector," said Edouard Taza, the president of Skytech.

Taza said he also reached out to Hamed Al-Khabaz, 20, and offered him a part-time job in information technology security.

Comment Re:How's that? (Score 4, Informative) 155

And how do you determine the age of some random rocky mass that you can't even image?

According to the BBC article, they simply guessed the age. The sub-brown dwarf or rogue planet seems to be travelling with a group of stars, and they've estimated the age of the stars to be 50 - 120 million years. It's a form of extra-solar profiling: That thing over there isn't a star, but it's hanging out with those other stars, so it must the same age as them. (Which is apparently OK to do for stars, but not people?)

Comment Re:I think that's all college students (Score 1) 823

Or perhaps you've heard the saying about 75% of people think they're above average? I'm sure there's a real study behind that, somewhere, but it strikes a chord for all of us, either way. ;)

It's easy for most of us to be above average, if the people at the bottom are far from the mean. Take five students writing a test: four of them score 50/100, one falls asleep and scores 0/100. The average score is therefore 40/100, and so 80% of the students scored above average. When you were thinking up the saying, you must have meant the mean not the average?

Comment He thinks $100 for an OS is expensive? (Score 1) 503

Getting Windows 7 from a shop is surprisingly expensive

He didn't even look. NewEgg is selling it for $99. A 30 day WoW subscription is listed on the Blizzard store for $15. So your OS costs less than 7 months of playing just one of the games you listed - tell me again what's expensive?

Submission + - Quantum measurements leave Schrödinger's cat alive (newscientist.com)

Walking The Walk writes: Your co-workers who keep using Schrödinger's cat metaphor may need to find a new one. New Scientist reports that

by making constant but weak measurements of a quantum system, physicists have managed to probe a delicate quantum state without destroying it – the equivalent of taking a peek at Schrodinger's metaphorical cat without killing it. The result should make it easier to handle systems such as quantum computers that exploit the exotic properties of the quantum world.


Comment Forced VOIP + Web Snooping (Score 2) 148

So, hot on the heals of a Slashdot story about Australia moving to fibre so they can push VOIP, we now get a story that states that they want to:

force all Australian telcos and internet service providers to store the online data of all Australians for up to two years

Yeah, don't worry - they're not related though. Really, we just think VOIP will improve everyone's lives.

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