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Comment Controlled for all factors? (Score 4, Insightful) 55

This bugs me: "Wind-tunnel experiments have shown that a patch of sand would take winds of about 80 mph to move on Mars compared with only 10 mph on Earth."

In order to move the sand, the wind must overcome friction. Sealed wind-tunnel experiments with different atmospheres can easily show that winds of low-pressure atmospheres need to have more energy to move sand than winds of higher pressure atmospheres.

But the wording of that statement doesn't mention gravity. In order to move the sand, the wind must overcome the force of friction, and of course friction depends on gravity. Did anyone adjust for Mars gravity being 38% of Earth's?

Comment Re:lasts for ages (Score 1) 254

I just bought my first ever cell phone (an iPhone 4S), and I did it because my iPod touch finally ran out of space.

Only my family and a few close friends have my number. Everyone else can continue to reach me through e-mail.

Comment My experience (Score 1) 405

I've run a voting booth for a Canadian federal election. Here's how it works.

A voter approaches and must be found on the list, and not marked as having already voted with an absentee ballot. I had a problem or two there.

I tear a perforated strip off the ballot and stuff it in a bag while giving an eligible voter the ballot. The strips are not identified but serve as a check on the number of ballots in the box.

At the end of the voting, all ballots are counted by hand. There is no electronic counting. The number of voters is validated by the names crossed off the list, by the paper strips, and by the ballots themselves. It's ridiculously easy to tell what a vote is as the ballot is all black with white names and a white circle for the voting mark. Party representatives may observe the counting.

Once the count is done, you report it to the head of the polling station. All ballots and documents are secured inside the taped-up ballot box kept.

There's only one real opportunity for fraud, and that's in the deciding for which candidate a ballot has been cast or if a ballot has been spoiled. That fraud has assuredly happened - and was completely ignored, with orders to destroy the ballots. It was a travesty, but at least the cheating side didn't win.

Comment Context (Score 1) 312

Robots/automation would be/are able to handle any of these tasks under perfect conditions. Google has cars that drive themselves with a passenger in the driver's seat, as mandated by law. As pointed out above, automatic pilots can already fly planes over the entire flight, rotations included. Food preparation may also been dome automatically, etc. etc.

Where robots may fail, al least at present, is in extreme conditions or when experience needs to be applied.

Let's look at planes. A robot can't see other than through its instruments. What if a pitot tube is clogged? How does a robot decide between a malfunctioning artificial horizon and the real one? Could a robot make emergency landings like the Gimli glider or Air Transat Flight 236? Could a robot detect the difference between a bird likely to fly away and a piece of debris on the runway before it decides to abort a full-speed take-off? I don't yet trust a plane without a pilot to oversee it.

Could a robot chef detect a leak that contaminates the food? A smear of motor oil?

Assuming there's some form of communication available, the least damage in a failure has to be a robotic ship. Navigation is simple, operation is slow, and the rules of emergency are fairly simple. The only real danger in malfunction is during docking, and even then the damage is primarily material with injuries rather than fatalities.

Cars and buses are dangerous as it is, not necessarily from robots, but from idiot drivers and cyclists.

If I'm putting my life in the hands of a robot today, it will be on a ship.


Mars Images Reveal Evidence of Ancient Lakes 128

Matt_dk writes "Spectacular satellite images suggest that Mars was warm enough to sustain lakes three billion years ago, a period that was previously thought to be too cold and arid to sustain water on the surface, according to research published today in the journal Geology. Earlier research had suggested that Mars had a warm and wet early history but that between 4 billion and 3.8 billion years ago, before the Hesperian Epoch, the planet lost most of its atmosphere and became cold and dry. In the new study, the researchers analysed detailed images from NASA’s Mars Reconnaissance Orbiter, which is currently circling the red planet, and concluded that there were later episodes where Mars experienced warm and wet periods."

Apple Orders 10 Million Tablets? 221

Arvisp writes "According to a blog post by former Google China president Kai-Fu Lee, Apple plans to produce nearly 10 million tablets in the still-unannounced product's first year. If Lee's blog post is to be believed, Apple plans to sell nearly twice as many tablets as it did iPhones in the product's first year."

Comment Netsurfer Digest (Score 1) 430

That was my baby, and we had been around for two years by 1996.

Our archive of back issues is available to all. Go cruise our 1996:

One sample issue, NSD 2.20, leads with the launch of Quake and the new MSNBC, whose DNS entry was suspended for lack of payment.

The main archive is here:

Comment Huh? (Score 4, Interesting) 200

I have no problem with the imterpretation that these are stone tools from 1.8 MYA (and you can tell by my pretentious use of the "MYA" abbreviation that I was once on the road to related Ph.D.).

But I don't understand this:

The stone hand-axes were discovered last year...embedded in a type of rock formed by meteorites....

How or why were these tools embedded in rock formed by meteorites? This rock was either formed before or after the tools. If formed before, they could only have been embedded manually, by H. erectus miners, I guess.

If the rock formed later, then these tools survived intact a meteorite strike, which seems unlikely. (Or was the rock formed by meteorite splash sediments?)

There is one other possibility, but it's so unlikely that I reject it: that the tools and rocks were thrown up in to the air and the whole mess coalesced and solidified.

I wish the article had more info, or I could find the original paper, although here is an AP article with a photo of the rocks.

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