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Comment Re:Local CO2 (Score 1) 42 42

I have seen arguments that it is ok to have CO2 measurement station on top of vulcano, because CO2 mixes so well

If you're referring to Mauna Loa weather observatory, the reason you can get accurate CO2 measurements on top of that volcano is that the active vents are all 20+ miles south, and the trade winds come from the west. There hasn't been an active caldera on top of the mountains since some time during the last ice age. If you read the summary a little more thoroughly you might have noticed that they're also measuring a number of other chemicals besides just carbon dioxide.

Comment Re:Simpler? (Score 1) 42 42

A sensor mounted on a building gives a sample of one location. Mounted on a car taking one sample per minute gives 480 geo-located samples that can be correlated to photos of the surroundings at that exact point in time in an 8 hour day. A map with one data point is pretty useless unless you happen to work or live in that building.

Comment Re:Why not read the number on the RFID chip? (Score 1) 26 26

ALL have tripwire to detect if they are opened

No, not actually (although your installer probably claimed they did). It can be done, but it's expensive, a pain in the ass to set up and false alarms are frequent. For the most part if you have a decent set of security tools you can get into the reader (although not the controller) and do what you want with it. As long as the cover stays the same and the functionality doesn't change (LED colors are right, flashing or not, door opens when it's supposed to) the main risk would be getting noticed playing with the reader.

Comment Re:Page loading has always been far slower with ad (Score 1) 375 375

there is reason to believe that the 'estimated' response for traditional media advertising has been vastly over-estimated.

That would explain the massive amount of junk mail still being sent out. I don't know anyone who opens the big thick envelope of ads that we get every Tuesday, or who has ever even leafed through the ten page advertising flyer that comes on Tuesday and Friday. The local bird-cage-liner newspaper claims a circulation of 40,000, but most of those never make it any further into the house than the recycle bin.

I guess I shouldn't complain though, the junk mail helps subsidize the USPS.

Comment Re:Hell, I'd buy it (Score 1) 550 550

Of course as an AC it wouldn't be possible to actually hold you to any sort of accountability so why not just volunteer to contribute a gazillion dollars? The last couple of years the number of Anonymous Cowards posting in every thread has exploded, while the average quality of their posts has deteriorated to only slightly better than what is found on Free Republic. I hope the buyer finds some way to get the AC plague under control. Something Awful got fed up enough they got rid of the Anon option entirely, and they never looked back.

Comment Re:Too Far Away (Score 1) 134 134

So you are assuming that radio astronomy will just stop advancing from today onward, or what? When Voyager was launched the ability to pick up the signal strength we're currently monitoring didn't exist. IIRC, to monitor the signal from Voyager is the equivalent of viewing a 60 watt light bulb in the orbit of Jupiter. In the next decade or so we'll have radio telescopes in orbit with baselines of tens of thousands of kilometers. Already Earth sends out more radiation than the Sun at several interesting wavelengths, we should be totally detectable within a sphere of 100 light years.

I think that, rather than a technical problem, detection of a civilization by monitoring the radio band is an issue of timing. After barely a century we're already moving away from high power radio broadcasts towards lower-powered directed communications, I don't see why another civilization wouldn't follow a similar path.

Comment Re:What will water be like on denser planets? (Score 1) 134 134

The density of the planet would refer to the average of the entire planet. Water won't be any denser just because the planet has more metal and less silicon, there just won't be much if any ground water because it won't be able to percolate very deep. Now if the gravity were five times greater the water would be denser (because it's effectively being compressed), and the gradient would be much steeper than comparable depths here on Earth.

Comment Re:Polynesians on Easter Island (Score 1) 103 103

Interesting. At least one type of Andean highland chicken, the 'chachara', carries the Chinese "frizzle" gene and may have been introduced by Chinese explorers in the 15th century. I hadn't realized there was evidence for the earlier presence of chickens. Thanks.

Comment Re:Drifters (Score 3, Interesting) 103 103

There has never been a land connection to Australia since the continent broke off from Africa shortly after the KT Event, which is why all the mammals were marsupials. The closest islands in the South Asian Archipelago (which themselves have never been reachable by land) could barely see mountain peaks in Australia on a clear day. The only way the Aborigines could have arrived was by boat or raft.

BTW, dingos arrived only about 4000-6000 years ago, the original immigrants appear to have arrived well before dogs and humans began living together.

Comment Re:Intercourse. (Score 2) 103 103

The last that I read there were at least three major influxes of immigration prior to the arrival of the European barbarians, and almost certainly multiple minor ones. That the Spaniards found people with red hair in South America and black skin in Central America when they arrived would seem to confirm the latter. Some minor influxes from Europe seem inevitable, particularly prior to the Viking domination of the North Atlantic, and Thor Heyerdahl showed that one-way trips from Africa were possible and in fact likely for any raft caught in the North Atlantic Gyre.

Considering that the Aborigines have been in Australia for as much as 60,000 years the antiquity of the progenitor population suggests a very early migration to North America as well. The extremely low population density and the fact that the coastline of the time (the most likely populated area) is now submerged make recovery of any artifacts unlikely, unfortunately.

Comment Re:On the topic of production... (Score 1) 617 617

My dad had one of the first Lowrance GPS receivers on the consumer market. About the size and weight of a brick, he used it until he passed away. It did exactly what he needed it to do and could survive laying in the bottom of the boat during a rainstorm, so he never saw the need to replace it.

"And do you think (fop that I am) that I could be the Scarlet Pumpernickel?" -- Looney Tunes, The Scarlet Pumpernickel (1950, Chuck Jones)