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Comment Re:R2D2 (Score 1) 23

"public outreach"
Quite correct.
But of course there are some useful scientific objectives to this research. These sounds are demodulated audio from radio waves captured from the magnetosphere surrounding Jupiter and Ganymede. Electromagnetic energy in the ELF/VLF/LF range (0-60kHz) from lighting and other discharges are trapped in magnetic force lines and circulated through the magnetosphere. Juno has a onboard electric dipole and magnetic search coil to receive E and B signals in this frequency emitted from Jupiter and modulated by Ganymede. The large rise and fall of the signal is due Doppler effect of the flyby on the received signals.
https://meetingorganizer.coper...

Comment Plus ca change ... (Score 2) 23

Think how "antiquated" this new "wafer scale" fabrication process is, reminiscent of the photogravure process used to prepare photographs for printing. The first example of this process, almost 200 years old now, is credited to Nicephore Niepce, who also is credited for making the first permanent photograph with a camera.

"A chip begins as a cylindrical ingot of crystallized silicon, about a foot across; the ingot gets sliced into circular wafers a fraction of a millimeter thick. Circuits are then "printed" onto the wafer, through a process called photolithography. Chemicals sensitive to ultraviolet light are carefully deposited on the surface in layers; UV beams are then projected through detailed stencils called reticles, and the chemicals react, forming circuits"

Nicephore used direct sunlight, in 1822, instead of UV, but the engraving process is essentially the same.
https://en.wikipedia.org/wiki/...

Comment Life is extremely adaptive (Score 4, Interesting) 56

"...100 times more powerful than any experienced in our solar system..."
So just because higher forms of life in our system would likely not survive such an event, it is not proof that life could not develop and continue to evolve in the Centauri system.

Life is a paradox. Extremely fragile, yet extremely robust.

Comment Re:MOND vs. dark matter (Score 2) 98

"There are some observations where MOND completely breaks down, most notably the Bullet Cluster."

MOND does not "completely break down" here, because there are plausible explanations for the lensing which do not require DM, according to Moti Milgrom, who created the MOND theory in 1982.
http://astroweb.case.edu/ssm/m...

Comment Re:Diversity of belief has been "redlined" (Score 1) 103

And yet flooding, fires, stronger hurricanes, droughts, batshit crazy weather showing up in unexpected places, plus real efforts at local mitigation are in real time.

I actually did not make such claims about those things in regard to re-analysis, except for the uncertainty/ambiguity it has introduced into meteorology. So, you must believe that all re-analyses are 'correct', even when they contradict each other? And you believe massive squelching freedom of thought and beliefs is a good thing?

But I (and many other skeptics) do believe that virtually all of that "it's worse than we thought" is pure alarmism. Extreme weather has always existed, even the kind of political propaganda you are quoting, in real time.

https://www.google.com/search?...
Are hurricanes getting worse? - Washington Times

Comment Diversity of belief has been "redlined" (Score 0) 103

"The article goes on to describe uses that analysts make of satellite data and GIS analysis," adds Slashdot reader mikeebbbd. "Is there a risk that this could create a modern version of 'redlining?'"

Yes, it is now very easy to see that political and mass media groups are systematically "categorizing" thoughts and beliefs, resulting in discrimination and prejudice against groups labeled "conservative".

As for using satellite data to "analyze" climate risk, be aware that it is really what is called "re-analysis". Instead of measuring "current" temperature directly with thermometers, reanalysis will apply computer models to "forecast" what the temperature outside "really" is, likely not the same value as your thermometer is telling you.

For example, the online "windy.com" weather tool uses reanalyzed satellite data to display "current" temperatures around the world, even in places where there are no thermometers.

Look at Antarctic for example, green denotes areas with temperatures above freezing. But this is "re-analysis", not directly observed temperatures, filtered by the ECMWF weather model. Click on "GFS" and you will get a different set of temperatures.

Comment Re:Help me out here (Score 1) 47

The warmer Southern Ocean is melting the glacier from underneath and they want to measure exactly what is happening. When the base of the glacier melts further, it will fall, slide, crack and create floating icebergs

The Southern Ocean forms a uniform band around the entire Antarctic Continent, relatively unobstructed by land masses as in the Northern Hemisphere.

So if the "warm", GHE-heated waters of the Southern Ocean are melting the Antarctic coast. Would not the melting occur uniformly around the continent? Yet it seems concentrated in "hot spots", such as Pine Island and the Thwaites Glacier.

And how is this warm water able to "sink" below the colder water above it? The usual pattern of ocean temperatures is a monotonic decline from the surface to the bottom, usually with a rapid drop in the thermocline.

A more believable theory to explain how the glacier seems to be melting from underneath surface would be exposure to enhanced geothermal flux from local volcanic "hot spots". This would create subglacial outflows from rock-ice interface and would also explain the apparent speedup of ice sliding out to the ocean over warmer rock.

In fact, such volcanic activity was discovered recently (2018) around Pine Island. Indeed many dozens of volcanoes are known lie under the West Antarctic Ice Sheet (WAIS):

Previously unsuspected volcanic activity confirmed under West Antarctic Ice Sheet at Pine Island Glacier
Potential effects of volcanic warming on ice-sheet melting and sea level rise still to be determined
https://www.nsf.gov/news/news_...

So, it may have nothing to do with Global Warming, which is primarily observed in the Northern Hemisphere, where the people live. (But CO2 is well mixed gas, so any CO2-induced warming should be uniformly observed in both hemispheres)

Comment Re:Remarkable (Score 3, Informative) 49

So, most of you do not know what is "spintronics", a fairly new magnetic paradigm in electronics fabrication, which will eventually replace most or all of the "conventional memory" chips that we use today, especially 'nor' and 'nand' flash memory, allowing faster and more efficient memory with virtually unlimited reprogramming. 'NOR flash' memory is currently limited to less than one million write cycles, because of HCI (hot carrier injection) which is responsible for allowing creation of non-volatile memory layers, but also destroys the device eventually from the intensive electron radiation ('beta rays') it creates.

The main idea is that all fermions (electrons, protons etc) have a property called 'spin', which allows them to be modelled as tiny magnetic dipoles with spin-up or spin-down polarity. In a default distribution, half are up and the other down. But this polarity can be controlled by an external field, to create "magnetic tunnel junctions" (MTJ), which can be used to re-design more efficiently devices currently using semiconductor P-N junctions etc.

"https://en.wikipedia.org/wiki/Tunnel_magnetoresistance"
https://en.wikipedia.org/wiki/...

"https://en.wikipedia.org/wiki/Spin-transfer_torque"
https://en.wikipedia.org/wiki/...

Comment Re:Evidence and predictions (Score 2) 331

A clean kill of the CO2-driven-climate hypothesis:
https://wattsupwiththat.com/20...

Sure, there is some global warming, due to a long-standing retreat from the Ice Age, less than 2C degrees a century and not correlated to CO2 rise. No big deal really.

Actually, it can be shown that there is virtually no global warming in Southern Hemisphere, discernible to microwave sensing satellites:
https://wattsupwiththat.com/20...

How that that be? Yes, most of the emissions come from the Nothern Hemisphere, but the CO2 is extremely well-mixed, so shouldn't both hemipsheres show roughly the same global temperature behavior? (Don't quote me "extreme temperature record broken _here_ or _there_". That's weather, not climate.)

Comment Re:What does this historically mean? (Score 1) 107

"Open fires were just that: open. And people weren't cooking 24 hours/day. People living in polluted areas are breathing this air 24 hours/day, potentially for their entire lives."

Humans (and humanoids) have been building "open fires" for cooking and warmth, inside their dwellings (hut, cave, igloo etc), for hundreds of thousands years, exposing women and children to this polluted air 24/7, (men were able to spend a little more time outdoors). Perhaps the most polluted areas in China are worse, where kids can grow up without ever seeing blue skies. But I think, on the whole, WHO is overstating this problem, as they tend to do.
https://www.nationalgeographic...

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