PaleoGeek - Slashdot User

Comment Re: Wondering if the US is behind it (Score 1) 175

by PaleoGeek on Saturday December 17, 2022 @02:26PM (#63138398) Attached to: GPS Signals Are Being Disrupted in Russian Cities

Selective availability is a capability that alters the clock signal on the satellite such that it degrades the precision of the civilian GPS signal, up to about 100 m. It is either on or off, for the satellite's civilian signal. It cannot be on for one part of the world and off for another. The GPS satellites ARE non-directional broadcasters. The US government has promised never to turn selective availability on again and the newest generation of satellites lacks the ability to turn on SA at all (https://www.gps.gov/systems/gps/modernization/sa/ ; 5 of the 31 operational satellites lack SA capability). Furthermore, the entire GPS constellation's signals are continuously monitored by many organizations around the world, and if SA was ever turned on it would be front-page news because it would endanger many people who depend on GPS.

GPS jamming, on the other hand, is all about affecting the signal strength received over a relatively small area of the Earth. As the article says, Russia has had the capability for years.

And in any case, TFA says the GPS signals are being checked by monitoring ADS-B data showing GNSS signal strength. SA does not affect signal strength. If GPS signal strength were reduced at the satellite, again it would be front-page news.

So, yes, most of the above is tin-foil bullcrap.

An Animal That Lives Without Oxygen 166

Posted by timothy on Wednesday April 07, 2010 @03:25PM from the besides-me dept.

Julie188 writes "Scientists have found the first multicellular animals that apparently live entirely without oxygen. The creatures reside deep in one of the harshest environments on earth: the Mediterranean Ocean's L'Atalante basin, which contains salt brine so dense that it doesn't mix with the oxygen-containing waters above."

Navy Wants Cyber Weapons That Shoot Data Beams 123

Posted by timothy on Saturday April 03, 2010 @12:50AM from the all-your-base-all-your-base-all-your-base dept.

ectotherm writes "By 2018, the US Navy hopes to equip its fighter jets with the ability to shoot data streams containing 'specialized waveforms and algorithms,' useful in an electronic attack or cyber-invasion. A few non-classified details here."

Dead Pigs Used To Investigate Ocean's "Dead Zones" 106

Posted by samzenpus on Thursday March 04, 2010 @03:55PM from the big-ocean-long-pig dept.

timothy writes "As places to study what happens to corpses, the Atlantic Ocean is both much larger and much more specialized than the famous 'body farm' in Knoxville, TN. But for all kinds of good reasons, sending human bodies into Davy Jones' locker just to see where they float and how they bloat is unpopular. Pigs don't pay taxes, and more importantly, they don't vote. So Canadian scientists have taken to using them as human-body proxies, to study what happens when creatures of similar size and hairlessness (aka, us) end up 86ed and in the drink."

Gamma Ray Mystery Reestablished By Fermi Telescope 95

Posted by Soulskill on Wednesday March 03, 2010 @12:23PM from the back-to-the-drawing-board dept.

eldavojohn writes "New observations from NASA's Fermi Gamma-ray Space Telescope reveal that our assumptions about the 'fog' of gamma rays in our universe are not entirely explained by black hole-powered jets emanating from active galaxies — as we previously hypothesized. For now, the researchers are representing the source of unaccounted gamma rays with a dragon (as in 'here be') symbol. A researcher explained that they are certain about this, given Fermi's observations: 'Active galaxies can explain less than 30 percent of the extragalactic gamma-ray background Fermi sees. That leaves a lot of room for scientific discovery as we puzzle out what else may be responsible.' And so we reopen the chapter on background gamma-rays in the science textbooks and hope this eventually sheds even more light on other mysteries of space — like star formation and dark matter."

Dinosaur Feather Color Discovered 219

Posted by timothy on Wednesday January 27, 2010 @05:28PM from the horsefeathers-still-a-mystery dept.

anzha writes "Do you remember being a kid and told we'd never know what colors the dinosaurs were? For at least some, that's no longer true. Scientists working in the UK and China have closely examined the fossils of multiple theropods and actually found the colors and patterns that were present in the fossilized proto-feathers. So far, the answer is orange, black and white in banded and other patterns. The work also thoroughly thrashes the idea that fossils might not be feathers, but collagen fibers instead. If this holds up, Birds Are Dinosaurs. Period. And colorful!"

Test Driving the Wolfram Alpha 124

Posted by kdawson on Sunday May 10, 2009 @10:44PM from the know-what-i-know-if-you-know-what-i-mean dept.

SilverMind writes in to note a blog entry at Byte Size Biology describing in detail a few hours spent with Wolfram Alpha (which we have discussed before). "After playing around with Wolfram Alpha for a few hours, I can safely say the following: it's different, it's incomplete, it's idiosyncratic, and it's funky cool. And no, it will not dethrone Google, nor does it aim to do so."

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