Early Earth's air weighed less than half of today's atmosphere

May 9, 2016
One of the lava flows analyzed in the study, from the shore of Australia's Beasley River. Gas bubbles that formed as the lava cooled, 2.7 billion years ago, have since filled with calcite and other minerals. The bubbles now look like white spots. Researchers compared bubble sizes from the top and bottom of the lava flows to measure the ancient air pressure. Credit: Sanjoy Som/University of Washington

The idea that the young Earth had a thicker atmosphere turns out to be wrong. New research from the University of Washington uses bubbles trapped in 2.7 billion-year-old rocks to show that air at that time exerted at most half the pressure of today's atmosphere.

The results, published online May 9 in Nature Geoscience, reverse the commonly accepted idea that the early Earth had a thicker atmosphere to compensate for weaker sunlight. The finding also has implications for which gases were in that atmosphere, and how biology and climate worked on the early planet.

"For the longest time, people have been thinking the atmospheric pressure might have been higher back then, because the sun was fainter," said lead author Sanjoy Som, who did the work as part of his UW doctorate in Earth and space sciences. "Our result is the opposite of what we were expecting."

The idea of using bubbles trapped in cooling as a "paleobarometer" to determine the weight of air in our planet's youth occurred decades ago to co-author Roger Buick, a UW professor of Earth and space sciences. Others had used the technique to measure the elevation of lavas a few million years old. To flip the idea and measure air pressure farther back in time, researchers needed a site where truly ancient lava had undisputedly formed at sea level.

Their field site in Western Australia was discovered by co-author Tim Blake of the University of Western Australia. There, the Beasley River has exposed 2.7 billion-year-old basalt lava. The lowest lava flow has "lava toes" that burrow into glassy shards, proving that plunged into seawater. The team drilled into the overlying lava flows to examine the size of the bubbles.

The layers on this 2.7 billion-year-old rock, a stromatolite from Western Australia, show evidence of single-celled, photosynthetic life on the shore of a large lake. The new result suggests that this microbial life thrived despite a thin atmosphere. Credit: Roger Buick/University of Washington

A stream of molten rock quickly cools from top and bottom, and bubbles trapped at the bottom are smaller than those at the top. The size difference records the air pressure pushing down on the lava as it cooled, 2.7 billion years ago.

Rough measurements in the field suggested a surprisingly lightweight atmosphere. More rigorous x-ray scans from several lava flows confirmed the result: The bubbles indicate that the atmospheric pressure at that time was less than half of today's.

Earth 2.7 billion years ago was home only to single-celled microbes, sunlight was about one-fifth weaker, and the atmosphere contained no oxygen. But this finding points to conditions being even more otherworldly than previously thought. A lighter atmosphere could affect wind strength and other climate patterns, and would even alter the boiling point of liquids.

"We're still coming to grips with the magnitude of this," Buick said. "It's going to take us a while to digest all the possible consequences." Other geological evidence clearly shows liquid water on Earth at that time, so the early atmosphere must have contained more heat-trapping greenhouse gases, like methane and carbon dioxide, and less nitrogen.

The new study is an advance on the UW team's previous work on "fossilized raindrops" that first cast doubt on the idea of a far thicker ancient atmosphere. The result also reinforces Buick's 2015 finding that microbes were pulling nitrogen out of Earth's some 3 billion years ago.

"The levels of nitrogen gas have varied through Earth's history, at least in Earth's early history, in ways that people just haven't even thought of before," said co-author David Catling, a UW professor of Earth and space sciences. "People will need to rewrite the textbooks."

The researchers will next look for other suitable rocks to confirm the findings and learn how might have varied through time.

While clues to the early Earth are scarce, it is still easier to study than planets outside our solar system, so this will help understand possible conditions and life on other planets where atmospheres might be thin and oxygen-free, like that of the early Earth.

Som is CEO of Seattle-based Blue Marble Space, a nonprofit that focuses on interdisciplinary space science research, international awareness, science education and public outreach. He currently does astrobiology research at NASA's Ames Research Center in California.

Explore further: Fossil raindrop impressions imply greenhouse gases loaded early Earth's atmosphere

More information: Sanjoy M. Som et al, Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels, Nature Geoscience (2016). DOI: 10.1038/NGEO2713

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Eddy Courant
1.9 / 5 (17) May 09, 2016
So much more CO2 and methane was available to encourage water vapor into the atmosphere. And water certainly boiled off with the lower pressure. RUNAWAY!!! >>>But it didn't.
ogg_ogg
1.4 / 5 (11) May 09, 2016
Interesting, if true. Seems to me the implications for Earth's geochemistry are pretty extensive, not to mention its biological evolution. It'll be interesting to see whether this catches on with the mainstream.
KBK
1.3 / 5 (12) May 09, 2016
this also tilts the recent drake equation calculation estimates.... to being more in favour of life.

Possibly..notably closer to the one in 10,000 range. Which means a veritable forest of life in the universe.
HannesAlfven
1.8 / 5 (21) May 09, 2016
Let's not forget that a thick atmosphere is commonly used to explain how the larger dinosaurs could have existed. So, unless the claim is now that the atmosphere's parameters swing around over time (contrary to uniformity), all we are now left with on that issue is a change in gravity.
jonesdave
4.1 / 5 (22) May 09, 2016
Let's not forget that a thick atmosphere is commonly used to explain how the larger dinosaurs could have existed. So, unless the claim is now that the atmosphere's parameters swing around over time (contrary to uniformity), all we are now left with on that issue is a change in gravity.


Don't be silly. When did the dinosaurs live? Was it 2.7 Ga? No, it was from ~ 250 Ma to 65 Ma. What was the bone structure of the large dinosaurs? How are you changing gravity? Why would you need to?
Honestly, you guys are crap enough at astrophysics; don't start wandering off into areas where you know even less.
tblakely1357
2.1 / 5 (17) May 09, 2016
Just when you think the 'science is settled' something comes along to upset the apple cart.
rojclague
1.1 / 5 (15) May 10, 2016
Interesting evidence of large changes in air pressure in the distant past.

1. The title of the letter published is Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels
2. A quote from the lead author is about "atmospheric pressure".
3. The abstract does not include the word weight..

However the author of the physics.org article replaces air pressure by "weight of air" and "lightweight". I don't think this is correct or necessary.

If you you agree it is OK then refer me to experimental evidence that the Earth's atmosphere or any amount of any gas has weight.

How can I weight air?
HannesAlfven
1.8 / 5 (20) May 10, 2016
Re: "Don't be silly. When did the dinosaurs live? Was it 2.7 Ga? No, it was from ~ 250 Ma to 65 Ma."

The finding makes a mockery of the common practice of assuming uniformity. You're failing to see the problem here, it seems, for the uniformitarian assumption ...

If it can be established that the Earth goes through big changes, then there's little reason to presume that these dates are correct to begin with because the dates themselves assume uniformity on a large host of parameters.

Those who are mired in the belief that atmospheric conditions swinging around bear nothing but technical problems to be solved have failed to grasp the bigger picture that an Earth which can be shown to be dramatically changing is not an Earth which we can reliably date.
bschott
1.7 / 5 (20) May 10, 2016
@HA - Very well stated, and well thought out.

How can I weight air?


Go diving. Weigh your tank when it is full, then again when it is empty. The difference in measurements is the weight of the air you took from the tank in order to dive, then exhaled into the water.
HannesAlfven
1.8 / 5 (21) May 10, 2016
I once took the time to learn all of the assumptions which go into just radiocarbon dating. It is now clear to me that people who place great faith in dates, in general, have never done the same. After all, most of the assumptions for radiocarbon dating, at least, have already been observed to be invalidated. And if you go to Willard Libby's original papers, you will see him obviously fudging the numbers, to begin with. It's not hard to notice because some of his most crucial datasets that he used to vindicate his technique involve just 10 or 20 data points.

The various dating methodologies are not accepted by the public because people have actually taken the time to establish for themselves personally that the techniques would work under real-world conditions; the dates are accepted because it makes us feel good to think that we know. It brings a sense of order to what is otherwise chaos.
Uncle Ira
2.7 / 5 (36) May 10, 2016
How can I weight air?
Take the empty vessel, record the tare weight using a scales. Pump a bunch more air into him using a compressor or such, then weight him again using the scales.

Any couyon that has ever bought propane by the pound, would know how to do it. At normal sea level, a square inch column weights about 14.7 lbs.
torbjorn_b_g_larsson
4.4 / 5 (14) May 10, 2016
I'm still not buying it.

Their raindrop paper was problematic - extending scaling laws without much support - and this letter supporting their theory seems a stretch too. But of course I have to read their new paper.

Having read their supplement, and having worked on log-normal distributions for inclusion growths in iron melts. their methods signals problems to me.

- They pick out bubbles they call amygdalas from a vast and varied size assortment. Then they use averages instead of raw values, suppressing data problems.

- Their data sets is too sparse (n ~ 100 - 300) to test for log-normal distributions as such, and indeed they don't do that but a gaussian fit in a logarithmic space.

A method that can be used is the bootstrap method they used in logarithmic space but on the original data. You can reconstruct both tails of the log-normal distribution with little error, and then make fits, tests, et cetera.

[tbctd]
physman
3.8 / 5 (16) May 10, 2016
@HannesAlfven The current value of the age of the Earth is not based on emergent effects like past composition of the atmosphere or temperature. Instead, it is based on the concentration of radioactive elements and the corresponding concentration of the known byproducts within a rock sample.

The ratios of these concentrations coupled with known half-life of the chemicals involved allows us to make very accurate predictions on the age of the sample. This is a nuclear process and as such is completely unaffected by any fluctuations in Earth's early conditions e.g. temperature. There is a remarkable consistency on the age of different samples from both the Moon and meteorites.
torbjorn_b_g_larsson
4.7 / 5 (13) May 10, 2016
[ctd]

- Using a logarithmic transformation suppress data problems and allows superficial fits of exponentials (gaussians).

- Despite that they have to throw away gaussian fits that gives negative pressure values, signaling that their method is erroneous.

But I admit to still not having read their pay-walled paper, nor having checked their statistical methods and tests.
HannesAlfven
1.4 / 5 (18) May 10, 2016
Re: "The current value of the age of the Earth is not based on emergent effects like past composition of the atmosphere or temperature. Instead ..."

Still not getting the problem ...

Large changes in Earth conditions imply an external influence. You're engaged in circular reasoning ... You're pointing to the large gaps in dates, with the HOPE that you can call any large changes gradual. But, what was the event which caused the large change? You don't know; you simply assume that the chronology is correct and throw away all data which disagrees.

Re: "This is a nuclear process and as such is completely unaffected by any fluctuations in Earth's early conditions e.g. temperature."

But, when you see evidence for a significant change, your decision to impose your narrative upon the data is simply a refusal to ask what caused those large changes?
torbjorn_b_g_larsson
4.7 / 5 (14) May 10, 2016
@HA: "radiocarbon dating".

Seriously, you 'dating' guys are laughable. (Do you get any, one wonders?)

You don't carbon date beyond 50 kyrs or so, 14C has a half life of 6 kyrs or so.

And as anyone who has had the energy to study dating methods know, isochron dating do not rely on uniformity, but on nonuniformity!

So you can always rely on those methods since they do not use other constraints than the raw data, they are self correcting for nonuniformities!

I don't know anybody that has claimed thick air allowed for dinosaur size. Instead today's dinosaurs reveal light weight, rapid growth construction with efficient lungs. And they had simple teeth, so small skulls in herbivores, who could harvest twice as fast as today's mammals.

But I know that highly oxygenated atmosphere in the Carbon era explains the size of insects at the time. That allowed their inefficient trachea system harvesting and distributing enough oxygen.

You are confused.
bschott
1.4 / 5 (19) May 10, 2016
Instead, it is based on the concentration of radioactive elements and the corresponding concentration of the known byproducts within a rock sample.


Thanks for the recap on carbon dating.

The ratios of these concentrations coupled with known half-life of the chemicals involved allows us to make very accurate predictions on the age of the sample


Assuming uniformity....

This is a nuclear process and as such is completely unaffected by any fluctuations in Earth's early conditions e.g. temperature.


You go by "physman" and you just said nuclear processes are unaffected by temperature?

https://www.techn...erature/

Lots of papers say otherwise.
HannesAlfven
1.5 / 5 (16) May 10, 2016
Re: "There is a remarkable consistency on the age of different samples from both the Moon and meteorites."

Your "remarkable consistency" completely ignores the blatant inconsistencies. You're also pointing to the very edge of the data set to make your case. What effort has truly gone into testing to see what happens to these dates when they are subjected to extreme electrical events? When you talk about dating meteorites, how can you claim to know at all the history of that object?

For many years, scientists refused to believe that rocks from Mars could ever achieve the escape velocity required to lift off of the planet. Now that such rocks have been confirmed to land on the Earth, you now assert that -- even though we were formerly perplexed about how this has happened -- now we are nevertheless sure that we can date the object.

Your confidence is easily confused for arrogance.
bschott
1.5 / 5 (17) May 10, 2016
Seriously, you 'dating' guys are laughable. (Do you get any, one wonders?)

You don't carbon date beyond 50 kyrs or so, 14C has a half life of 6 kyrs or so.


So are you guys who assume he could only be talking about carbon dating.

Uranium-lead for time scales on the orders of hundreds of millions or billions of years maybe?

Still affected by temperature though.

Your confidence is easily confused for arrogance.


It's both.
HannesAlfven
1.6 / 5 (14) May 10, 2016
Re: "I don't know anybody that has claimed thick air allowed for dinosaur size. Instead today's dinosaurs reveal light weight, rapid growth construction with efficient lungs. And they had simple teeth, so small skulls in herbivores, who could harvest twice as fast as today's mammals."

These "solutions" simply raise additional questions. Further, they ignore Galileo's square-cube law, which places an upper limit on a land-walking animal at elephants. You seem to want us to believe that these simple calculations are a coincidence.
physman
3.9 / 5 (15) May 10, 2016
@HannesAlfven I'm not quite sure how to begin to reply to that stream of noninformation. I can see by your combative tone that you are interested in a fight but will refuse to listen to what I have to say, I won't waste my time on you thanks.
HannesAlfven
1.3 / 5 (16) May 10, 2016
@physman Your faith in dates constitutes a refusal to ask crucial questions. I doubt anybody will notice the loss.
physman
3.8 / 5 (13) May 10, 2016
@bschott from your linked article (if you bothered to read to the bottom...) they talk about the updated more accurate results:

Their results? Zip, zilch, zero. They found no temperature dependence in any of their data.

You just debunked yourself.

Edit: here's the paper too http://arxiv.org/abs/0910.4338
bschott
1.3 / 5 (15) May 10, 2016
@bschott from your linked article (if you bothered to read to the bottom...) they talk about the updated more accurate results:

Their results? Zip, zilch, zero. They found no temperature dependence in any of their data.

You just debunked yourself.

Edit: here's the paper too http://arxiv.org/abs/0910.4338


Um no. One study found no difference, the one you like and that was linked at the bottom of the article I linked....they named several studies that did observe a difference. I guess i should have gone right to my arena:

http://www.0095.i...emp.html

Your statement was far too broad, especially considering the temperatures present inside the earth today and during it's formation.
TehDog
4.7 / 5 (15) May 10, 2016
Here's the home page for bschot's link;
http://www.0095.i...sen.html
"95 One Sentence Theses against Evolution"
Seriously?
Uncle Ira
2.7 / 5 (39) May 10, 2016
Here's the home page for bschot's link;
http://www.0095.i...sen.html
"95 One Sentence Theses against Evolution"

Never I mind, no way I could top that. But thanks anyhoo, I will mark him up and put him in the same drawer I keep Really-Skippy's Earthling House in.

Seriously?
It is a shame I know, but I think he is.

Oh yeah, I almost forget. TehDog-Skippy, I owe you a great big thank you. THANK YOU (That's as big as they will let me write it here.) Awhile back you recommended the LibreOffice to somebody. I really hated the way the Word slowed up my computer and always wanted something else that would do the same stuffs. So I tried the LibreOffice and so did Mrs-Ira-Skippette. We both love it, a lot. Anybody else, if you want something better than the MS Word, give it a try.

Captain Stumpy
4 / 5 (21) May 10, 2016
Seriously?
@tehdog
yeah, he is likely serious...

take his acceptance of magnetic magic super-anti-cancer machines... so long as he sees someone saying "it worked for me" then it is a fully functional machine despite no FDA approval:
http://phys.org/n...ant.html

http://phys.org/n...apy.html

so why would he not post creationist literature, like above

of course, refute of his linked site is easy: http://www.talkor...comdesc/

http://www.talkor...ing.html

http://www.talkor...ing.html

http://www.talkor...rth.html

http://www.talkor...rth.html

and those links contains plenty of validated studies as reference material, if he cares to review them
(or anyone else cares... enjoy it)
Captain Stumpy
4 / 5 (21) May 10, 2016
Awhile back you recommended the LibreOffice to somebody
@Ira
he suggested it to ME... and i LOVE IT

so i owe you a great big thank you too, tehDog
THANK YOU

LOL
Anybody else, if you want something better than the MS Word, give it a try.
Also note... if yall don't like the problems that Windows likes to give you... try loading Linux as well
It is far easier, FASTER and it doesn't have near the problems that windows does

in fact, my 7 year old laptop running Linux (Ubuntu) runs faster and better with 1/4 the RAM than my year old Quad-core running WIN10 with 4 times the RAM and about 8Gig expanded cache readyboost on card and USB...

think on that a spell

plus Linux has a community to address problems immediately ... not like windows

Thanks TehDog
TehDog
4.5 / 5 (15) May 10, 2016
@Ira
"Never I mind, no way I could top that."
I was seriously, totally, lost for words :) It does rank up there with RC's work.

@CS&I
Yeah, LO is very good, also has the added advantage of not being a common attack vector.
I'm a fan of open source stuff, these days it's not usually too hard to find excellent alternatives to commercial SW.
I've found Ubuntu works well for those just needing an everyday replacement for windows, altho it can be tricky installing some programs (I had problems getting Teamspeak set up on a laptop).
It does provide a good incentive to learn unix :)
"readyboost on card and USB..."
Assuming that's an SD card, they are slow, and unless it's a usb3 device in a usb3 socket
it's not really worth it, plus don't forget that flash wear is related to the number of writes. Get an SSD, install OS, boot from cold to usable desktop in ~30 secs. Keep the spinny thing for bulk storage.
HannesAlfven
1.6 / 5 (14) May 10, 2016
Can somebody here point me to a paper where a material resembling a meteorite is subjected to impact-like conditions which would be sufficient to lift the material off of Mars, and then the before and after dates are compared?

I'm assuming that somebody has already tested this. Thanks in advance for your help.
Uncle Ira
2.7 / 5 (37) May 10, 2016
Can somebody here point me to a paper where a material resembling a meteorite is subjected to impact-like conditions which would be sufficient to lift the material off of Mars, and then the before and after dates are compared?
Well I took the lookee-loo. Non, I could not find one.

I'm assuming that somebody has already tested this.
Well I will assume right back at you. I'm assuming you can think of a way to do that thing you are assuming somebody has done. Could you explain how you would go about it?

Thanks in advance for your help.
De rien Cher, it was a small thing.

Now I got the question for you, fair is fair, right?

Can the EU Skippys here point me to a paper where a material resembling a meteorite is subjected to impact-like conditions which would be sufficient to lift the material off of Mars, and then the before and after dates are compared? I assume the EU Skippys have got a lot testing under their belts, what happened when you did it?
HannesAlfven
1.5 / 5 (15) May 10, 2016
Re: "Can the EU Skippys here point me to a paper where a material resembling a meteorite is subjected to impact-like conditions which would be sufficient to lift the material off of Mars, and then the before and after dates are compared? I assume the EU Skippys have got a lot testing under their belts, what happened when you did it?"

No, but let's not forget that the EU group has not constructed an elaborate, detailed timeline that bases upon a presumed answer to this question, either.

My understanding of the way this works is that dates that do not fit the timeline consensus are presumed wrong, and those data points are simply discarded. Am I somehow wrong about this?
Uncle Ira
2.6 / 5 (40) May 10, 2016
No, but let's not forget that the EU group has not constructed an elaborate, detailed timeline that bases upon a presumed answer to this question, either.
Well I should hope not. Because if you,,,,,,

point me to a paper where a material resembling a meteorite is subjected to impact-like conditions which would be sufficient to lift the material off of Mars, and then the before and after dates are compared?


,,,, comparing the before and after dates are not going to give you much to go on. Check my material on Monday, do the experiment on Wednesday because it was raining on Tuesday, and check my materials again on Thursday or Friday. That is what you were asking to do, right?
HannesAlfven
1.5 / 5 (16) May 10, 2016
This experiment is absolutely crucial. Common sense suggests that such an event would completely alter the dates. How is the question. We can even form a reasonable hypothesis going into the experiment that any sample subjected to such conditions would likely register the very dates which are today said to be "remarkably consistent" for both the Moon and meteorites.

Your confidence in these dates relies heavily on science's continued refusal to ask such crucial questions. These are truthfully obvious questions. Space is obviously a violent place. The Moon has very obviously been through a lot of sh*t. It's littered with glass melt. Meteorites from Mars have obviously been subjected to very violent conditions.

This is not rocket science, people.
TehDog
4.7 / 5 (14) May 10, 2016
@HA
So you want to know the C14 ratios of a chunk of Mars before it was ejected, and the ratios when it was found on Earth? Just checking...
"I'm assuming that somebody has already tested this."
How?
Uncle Ira
2.5 / 5 (39) May 10, 2016
This experiment is absolutely crucial.
Kind of full of your self there Skippy, eh?

Common sense suggests that such an event would completely alter the dates.
Common sense would suggest to me that these scientists probably know a whole more about this than some interweb crankpots and couyons wasting their time on physorg.

How is the question.
Why you asking me how? Maybe you would get a better answer from the peoples who did the studying, eh?

We can even form a reasonable hypothesis going into the experiment that any sample subjected to such conditions would likely register the very dates which are today said to be "remarkably consistent" for both the Moon and meteorites.
Then do the experiment and report back to us. You assumed somebody has done it, I assumed it was an experiment that can't be done. So do it and make your self really famous (a lot more famous than you will get writing silly stuffs on the interweb.)
HannesAlfven
1.5 / 5 (15) May 10, 2016
Re: "How?"

You're smarter than this.

You start with lightning. Take a specimen of known age, place it at the top of a lightning pole, wait for a strike, then re-date.

Next, try various explosives.

Don't forget fire.

Why not an intense laser?

The z-machine ...

Did I really need to make these suggestions? You guys understand this already. Start out small; if the lead pans out, go bigger.

Stop playing dumb.
Uncle Ira
2.6 / 5 (38) May 10, 2016
You're smarter than this.
Well apparently I am not.

You start with lightning. Take a specimen of known age, place it at the top of a lightning pole, wait for a strike, then re-date.
Why I got to do it? You can do it your self if you want to do.

Next, try various explosives.
I'll pass on that. If I did not blow my self up, I would probably end up in the jail.

Don't forget fire.
Thanks for reminding me about that, I'll try to remember.

Why not an intense laser?
I don't have one. And I am not having the urge to go out and buy one either. If you got one, and you bring him on down to Louisiana, I will let you choot the rocks with the laser in my backyard (pending Mrs-Ira-Skippette's permission.)

The z-machine ...
Well I think, and have a really strong feeling, Mrs-Ira-Skippette will draw the line with that.

Stop playing dumb.
I will do that, but you got to go first and show me how it's done.
TehDog
4.5 / 5 (16) May 10, 2016
@HA
"Re: "How?"
You're smarter than this."
You start with lightning. Take a specimen of known age..."

Of what? A Martian meteorite? But that's already been subjected to the kind of event you seem to think would alter decay rates, so how could that measurement mean anything?

"Don't forget fire."

Now you're just being silly.
Zorcon
2.6 / 5 (12) May 11, 2016
"The lowest lava flow has "lava toes" that burrow into glassy shards, proving that molten lava plunged into seawater."

Why couldn't it have plunged into a high altitude lake?
rojclague
1.8 / 5 (15) May 11, 2016
How can I weight air?


Go diving. Weigh your tank when it is full, then again when it is empty. The difference in measurements is the weight of the air you took from the tank in order to dive, then exhaled into the water.


The difference in down force measured is caused by the reduction in the pressure.

Weigh a basket ball deflated. Pump up to 1 atm. Weigh it agian. There is no change in weight.

I want an example of weighing air without a cahnge in pressure.
torbjorn_b_g_larsson
5 / 5 (12) May 11, 2016
@Zorcon: I think they are testing the altitude they have estimated from other sources, such as coastal sediments under the lava cover et cetera.

I don't think that is where the problem lies, but in their convenient but likely erroneous (at least weak and inconsistent) data picking and fitting.

@bschot: "Assuming uniformity...".

Not assuming uniformity... in isochron methods. They extract the ages irrespective of half life and its changes. You have no outer constraints, it is self dating. Look it up!
torbjorn_b_g_larsson
4.7 / 5 (13) May 11, 2016
@HA: " ignores the blatant inconsistencies", "These "solutions" simply raise additional questions. Further, they ignore Galileo's square-cube law,".

Unsupported claims, as is the rest of your comments. Physiologists agree that dinosaurs sizes and masses are consistent with the environmental conditions. And those conditions are much like today, it was just 60 Myrs ago after all. (Hotter at the equator, but much the same atmosphere.)

But this, like your martian meteorite problem, is blatant side tracks to the work discussed here. We are discussing air pressures at a time there were no dinosaurs, no insects and meteorites and precise dating doesn't come into it. You can date these sediments from average deposition rates if you will, you will still end up with billions of years age.

[tbctd]
torbjorn_b_g_larsson
5 / 5 (12) May 11, 2016
[ctd]

[I don't get your questions on meteorites, but you can look martian meteorites and their sourcing, dating et cetera up. Travel times are recorded in cosmic radiation traces, as I remember it. And obviously a hypervelocity large asteroid orbiting at 20 km/s or more can launch spallated crust fragments against Mars 8 km/s escape velocity as they (fail to) cross orbit, relative velocities would be around the 20 km/s value.]

@rojclague:

"I want an example of weighing air without a cahnge in pressure."

Relevance, and why that constraint? The article is cute when it discusses mass (weight) instead of pressure of the gas. The idealized gas law, derived from knowing that gas are massive particles, show that you can describe either. That is a way to measure mass at ambient pressure.

When you pump up your ball, don't forget to measure the change in weight of your gas tube. It will be equal to the weight change of the ball, obviously.
antialias_physorg
4.7 / 5 (12) May 11, 2016
Why couldn't it have plunged into a high altitude lake?

Not even the highest altitude lakes would produce such a low pressure reading
Remember that for this to work you have to have a volcano that is higher up than that. The current record holder for a volcano is less than 7000m high (the highest lake is about 6000m high)
Captain Stumpy
3.8 / 5 (16) May 11, 2016
...point me to a paper ...material resembling a meteorite is subjected to impact-like conditions
@HA
this will be multiple papers across disciplines
but it is also how science works and can give you computers from silicon

we know what meteorites are typically comprised of by observation, measurement, etc like: http://www.scienc...9599860T

we have materials science with the same materials, like: http://www.scienc...79901653

we even know about microorg's etc: http://www.scienc...02003691

we even studied explosive effects and impacts in earth atmosphere/gravity and can extrapolate this to a martian atmos with less gravity

so what you're asking for is not a singular study but likely about at least a dozen studies
try this link: https://scholar.google.com/

before you post eu "belief" find real facts and learn what is out there
Uncle Ira
2.5 / 5 (38) May 11, 2016
I want an example of weighing air without a cahnge in pressure.
Take your self a tank of air and weigh him real good in your back yard. Then take him up to the moon (with your scales) and weigh him again. The pressure in the tank stays the same but the weight changes because of the gravity. Weight is nothing more than the force of gravity.

All this asking of the really "good" questions. Why it is you think that air don't have any weight? Fair is fair right? We answered your "profound" and "deep" question, now it is your turn. Explain why you think air is weightless.
Captain Stumpy
3.9 / 5 (18) May 11, 2016
@ha cont'd
You start with lightning..
sigh... really?
1- being able to think logically and critically is about being able to research information from across disciplines, like i showed you above

2- it's not just about lightning and plasma... there really are other materials out there in the universe

3- if you want to know the answer, try following the above suggestions and seeking information before you start pontificating about what your eu-cult says

materials science is a well developed field with a lot of information (some of it proprietary and protected)

this is directly related to your posts about Kahneman's model - your "fast thinking" brain always reacts with eu beliefs, not critical thought, research or even logic

science adapts based on new information (See Newtonian gravity) - this is something you and the eu don't ever do. it's always plasma or electric something

reality says: science works
Captain Stumpy
3.9 / 5 (18) May 11, 2016
I want an example of weighing air without a cahnge in pressure
@rojclague
well, start with the atomic weight of oxygen and all the other constituent molecules of typical breathing air (like Nitrogen... don't forget diatomic particles)

then count the molecules of air in your tank, and don't forget about density

you can also just search Google for "how heavy is air"
http://www.scienc...eavy-air

or how to measure how heavy air is
https://van.physi...?id=2205

http://littleshop...hing.pdf

http://practicalp...air.html

enjoy
Uncle Ira
2.5 / 5 (40) May 11, 2016
The difference in down force measured is caused by the reduction in the pressure.
You got that backwards. The difference in pressure is cause by the change in "down force".

Weigh a basket ball deflated. Pump up to 1 atm. Weigh it agian. There is no change in weight.
There is Cher, but just a tiny little minuscule change.

I want an example of weighing air without a cahnge in pressure.
Skippy, I will give to you the benefit of the doubt, maybe you are not just trolling. Last chance on that though, eh?

Weight is not dependent on pressure. Weight has to do with the gravity and mass of a particle. Pressure is not dependent on the mass of the particle, only the number of particles, the volume of the container and temperature.

So here is how you weight the air without changing the temperature. I'll P.S. you with the rest because I am running out of letter spaces,,,
Uncle Ira
2.5 / 5 (39) May 11, 2016
I want an example of weighing air without a cahnge in pressure.


So here is how you weight the air without changing the temperature.

Take a super duper NASA grade set of balance beam scales, eh? You got to have two identical tanks that tare empty the same weight, eh? Pump one full of air to what ever pressure. Pump up the other with hydrogen to the exact same pressure, eh? Put them on your balance beams and you will see that the air is heavier (weights more) than the same pressure and size tank of hydrogen.

All other things being equal, pressure is dependent on volume, temperature and number of particles. Weight don't figure into it. A container with X number atm of hydrogen will have the same number of particles as X number atm of "air". But it will weigh less because hydrogen particles have less mass than "air" particles.

That is my best attempt to help, maybe one of the scientist trained Skippys will chime with something better.
Zorcon
2.7 / 5 (12) May 11, 2016
How can I weight air?


Go diving. Weigh your tank when it is full, then again when it is empty. The difference in measurements is the weight of the air you took from the tank in order to dive, then exhaled into the water.


The difference in down force measured is caused by the reduction in the pressure.

Weigh a basket ball deflated. Pump up to 1 atm. Weigh it agian. There is no change in weight.

I want an example of weighing air without a cahnge in pressure.

Then liquefy it and weigh it at ambient pressure.
bschott
1.3 / 5 (18) May 12, 2016
Here's the home page for bschot's link;
http://www.0095.i...sen.html
"95 One Sentence Theses against Evolution"
Seriously?


LMAO....there were a lot of papers which refuted the statement made by physman regarding temperature and nuclear processes, are you agreeing with his statement? Or just being petty?

then it is a fully functional machine despite no FDA approval:


So you believe only FDA approved machinery is functional? Figures.

Captain useless goes completely off topic as usual in an attempt to make a personal attack, just because he thought he saw a hole in something I was saying. So captain, do you agree with Physmans assertion that temperature doesn't affect nuclear processes?

This is a science question so you may want go next door to the grade sixes if you are finding it too difficult to understand.
antialias_physorg
5 / 5 (9) May 12, 2016
Weigh a basket ball deflated. Pump up to 1 atm. Weigh it agian. There is no change in weight.

If you weigh the two in a vacuum chamber there is a change.

If you weigh it outside a vacuum chamber there isn't because the volume of the air you took out now resides above the basketball (in the space the filled basketball would have occupied). So you are weighing that, too.

barakn
1 / 5 (16) May 12, 2016
Weight is not dependent on pressure. Weight has to do with the gravity and mass of a particle. Pressure is not dependent on the mass of the particle, only the number of particles, the volume of the container and temperature. -Uncle Ira
While you have a good grasp of the ideal gas law, it assumes a container and constant gravity throughout the container volume, both of which do not apply to Earth's atmosphere. Keeping in mind that pressure is force per unit area, and weight is a measurement of force, every measurement of atmospheric pressure is a measurement of the weight of a column of air divided by the area that column is hovering over. For example, at 1 atmosphere, 14.7 psi, we can interpret that as meaning that at sea level, there's roughly 14.7 pounds of air over every square inch of land/sea.
Uncle Ira
2.7 / 5 (37) May 12, 2016
While you have a good grasp of the ideal gas law, it assumes a container and constant gravity throughout the container volume, both of which do not apply to Earth's atmosphere.
In Earth's atmosphere, gravity IS the container.

Keeping in mind that pressure is force per unit area,
I said that

and weight is a measurement of force,
I said that one too.

every measurement of atmospheric pressure is a measurement of the weight of a column of air divided by the area that column is hovering over.
I said that too. But all this is the distractions, he wanted to know how to measure how much air weights. I told him several ways to do it.

there's roughly 14.7 pounds of air over every square inch of land/sea.
That is EXACTLY what I said somewhere up there. I was not the one getting pressure and weight (force due to the gravity) mixed up, that was somebody else not me.
HeloMenelo
2.9 / 5 (17) May 12, 2016
Here's the home page for bschot's link;
http://www.0095.i...sen.html
"95 One Sentence Theses against Evolution"
Seriously?


LMAO....there were a lot of papers which refuted the statement made by physman regarding temperature and nuclear processes, are you agreeing with his statement? Or just being petty?

then it is a fully functional machine despite no FDA approval:


So you believe only FDA approved machinery is functional? Figures.

Captain....

This is a science question so you may want go next door to the grade sixes if you are finding it too difficult to understand.


monkeyyyyyy :D antigoracle's sockpuppet struggle to get past mental school as Captain flushes him a full ace as always, well done Captain, Now for some laughs, se bschott, an antigoracle sock slaps himself in the face telling lies right here as his other sock obama socks :D

http://phys.org/n...ate.html
Phys1
4.6 / 5 (10) May 12, 2016
Weight is not dependent on pressure. Weight has to do with the gravity and mass of a particle. Pressure is not dependent on the mass of the particle, only the number of particles, the volume of the container and temperature. -Uncle Ira
While you have a good grasp of the ideal gas law, it assumes a container and constant gravity throughout the container volume, both of which do not apply to Earth's atmosphere. Keeping in mind that pressure is force per unit area, and weight is a measurement of force, every measurement of atmospheric pressure is a measurement of the weight of a column of air divided by the area that column is hovering over. For example, at 1 atmosphere, 14.7 psi, we can interpret that as meaning that at sea level, there's roughly 14.7 pounds of air over every square inch of land/sea.

You are both right.
Phys1
4.5 / 5 (8) May 12, 2016
Instead, it is based on the concentration of radioactive elements and the corresponding concentration of the known byproducts within a rock sample.


Thanks for the recap on carbon dating.

The ratios of these concentrations coupled with known half-life of the chemicals involved allows us to make very accurate predictions on the age of the sample


Assuming uniformity....

This is a nuclear process and as such is completely unaffected by any fluctuations in Earth's early conditions e.g. temperature.


You go by "physman" and you just said nuclear processes are unaffected by temperature?

https://www.techn...erature/

Lots of papers say otherwise.

Then lots of papers are wrong.
rojclague
1 / 5 (13) May 12, 2016
Uncle Ira says:
"All other things being equal, pressure is dependent on volume, temperature and number of particles. Weight don't figure into it. A container with X number atm of hydrogen will have the same number of particles as X number atm of "air". But it will weigh less because hydrogen particles have less mass than "air" particles."

Weigh less should be has less mass. Mass is not weight.
Otherwise you make a good point.

A mole of hydrogen 2g and a mole of nitrogen 28g create the same pressure (at same volume and temperature). Pressure depends on number of particles not mass of gas.

If pressure does not depend on mass then it cannot be caused by weight.
Solid and liquid have weight, gas does not. Gas pressure is not caused by weight.

Gas pressure is caused by change of momentum
bschott
1.3 / 5 (16) May 12, 2016
monkeyyyyyy :D antigoracle's sockpuppet struggle to get past mental school as Captain flushes him a full ace as always, well done Captain, Now for some laughs, se bschott, an antigoracle sock slaps himself in the face telling lies right here as his other sock obama socks :D


Apparently Helomonelo was having a seizure while trying to type ...something. And is as perceptive as, well, a person having a seizure.

Then lots of papers are wrong.


I agree completely. But not the ones written around EXPERIMENTS which PROVE nuclear processes ARE affected by temperature, have you ever heard of critical ionization values? Or possibly wondered why gases become plasma at certain T-E-M-P-E-R-A-T-U-R-E-S. These would be nuclear processes affected by temperature.
Uncle Ira
2.6 / 5 (34) May 12, 2016
If pressure does not depend on mass then it cannot be caused by weight.
That is wrong Cher. 1000 molecules of hydrogen in a bottle will have the same pressure as 1000 molecules of oxygen in the same container. But the container of oxygen will weigh more.

But didn't you know some gases sink in air? And others float in air? That's right, they do, because some gases because heavier. It's why your balloons float. Yeah Cher that's true.

Solid and liquid have weight, gas does not.
An atom has mass, so in the presence of gravity it has weight. Don't matter if the atom is in a solid, the liquid or the gas, that same atom has the same mass, and in the same gravity field it will have the same weight.

Gas pressure is not caused by weight.
Depends on the situation. Don't this belong on the "there is no hydrogen fusion in the sun" articles? That's where you tried him out last time. You know, "gravity can't power the sun" arguments?
Uncle Ira
2.7 / 5 (35) May 12, 2016
I tell you what it looks like to me. It looks like A2G, rubberman, no-fate, reset, bachott, their et al's are morphing into the new and improved Prime-Magnet-Universe-Skippy again. Well, none of are really that much improved than the last one, and they are not that much new either, but you know what I mean. Every six months a new one tries again.

How about it Cher? Roclug-Skippy, that is you isn't it?
bschott
1.3 / 5 (15) May 12, 2016
I tell you what it looks like to me. It looks like A2G, rubberman, no-fate, reset, bachott, their et al's are morphing into the new and improved Prime-Magnet-Universe-Skippy again. Well, none of are really that much improved than the last one, and they are not that much new either, but you know what I mean. Every six months a new one tries again.

How about it Cher? Roclug-Skippy, that is you isn't it?


No Ira, I went with my actual name and i am sticking to it for the rest of my tenure here. But if you want to talk about fake skippy's...I have a few questions about driving tug's in certain circumstances that you can't google the answers to but any actual tug operator has to know, wanna try em out?"
TehDog
4.8 / 5 (16) May 12, 2016
@bschot

"You go by "physman" and you just said nuclear processes are unaffected by temperature?

https://www.techn...erature/

Lots of papers say otherwise."

The article you cited does not support this statement.
Neither does the paper the article is reporting on,

http://arxiv.org/...38v1.pdf

When this was pointed out to you, you linked to a creationist blog.
The page you linked specifically was,

http://www.0095.i...emp.html

This cites 2 papers by Edward Boudreaux, (spelled Edward Boudraux)

https://www.googl...;bih=851

This is a sample of his work,

http://creation.c...six-days

And you wonder why I went "Seriously?"
Uncle Ira
2.6 / 5 (35) May 12, 2016
I have a few questions about driving tug's in certain circumstances that you can't google the answers to but any actual tug operator has to know, wanna try em out?


Give it your best shot Skippy.
Uncle Ira
2.7 / 5 (36) May 12, 2016
@ Bachott-Skippy. I forgot to tell you in case you did not know. I don't work on tug's, I work on towboats, they are different. But I can probably answer those ones too because way back in the day, I also worked on ocean tugs and crewboats.
Phys1
4.6 / 5 (11) May 12, 2016
why gases become plasma at certain T-E-M-P-E-R-A-T-U-R-E-S. These would be nuclear processes affected by temperature.

Do you even know what the term "nuclear" means?
Your are voicing opinions about subjects on which you have no competence whatsoever.
Nobody in his right mind can take your posts seriously.
Consistently nonsensical.
viko_mx
1 / 5 (9) May 13, 2016
"New research from the University of Washington uses bubbles trapped in 2.7 billion-year-old rocks..."

How this "researchers" can be sure that the isotopic clock which use to obtaint the age of this rocks is started form zero? In other words, how they can be sure that their isotopic clock have contained at the start moment only the main isotope without the subsidiary isotopes. How can be sure that their isotopic clocks is remained intact closed system without external influence of the physical environment throughout the whole period of its real existent.
rojclague
1.3 / 5 (15) May 13, 2016
Uncle Ira says:

"An atom has mass, so in the presence of gravity it has weight."

Astronauts in the ISS have mass and are in the presence of 90% of the surface gravity on Earth. . They are weightless.

"Don't matter if the atom is in a solid, the liquid or the gas, that same atom has the same mass, and in the same gravity field it will have the same weight."

I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.

The atmosphere, like many other things, is weightless.

Mass does not always cause weight. Weight is unusual. It is only caused by mass which is prevented from moving by a solid surface.
viko_mx
1 / 5 (10) May 13, 2016
Its makes an impresion how the unnutural for the scientific community voting system inplemented for the anonyms polit correct voters traditionally rewards the mediocrity for inefective triаl to shape public opinion.
Uncle Ira
2.6 / 5 (35) May 13, 2016
Astronauts in the ISS have mass and are in the presence of 90% of the surface gravity on Earth. They are weightless.
That must be why they are in the constant state of free falling, eh? The reason the ISS don't fly off in a straight line is because of it's weight.

I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.
Actually you do feel it Cher.

The atmosphere, like many other things, is weightless.
Why we don't cut to the chase, eh? This would be a good place to go ahead and tell us that it is the Prime Magnets that hold the air to the earth and not really the gravity.

Mass does not always cause weight.
In the presence of gravity it does.

Weight is unusual.
Only for you.

It is only caused by mass which is prevented from moving by a solid surface.
That is unusual.

You over played your hand Skippy. Maybe someone else will play with you.
antialias_physorg
5 / 5 (12) May 13, 2016
I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.

You do. Try going into a vacuum chamber and see how the difference feels when it's gone.

Mass does not always cause weight.

Mass times acceleration is weight (F = m * a). On Earth a = g

A mass that does not feel an acceleration (e.g. a mass that is far away from another mass or one in free fall) does not have weight.
Jump out a plane or go into orbit and you're weightless. The orbit of e.g. the ISS is where its momentum to move off into space (Newtons second law) is counterbalanced by gravity - and hence only a motion with constant distance remains.
torbjorn_b_g_larsson
5 / 5 (12) May 13, 2016

A mole of hydrogen 2g and a mole of nitrogen 28g create the same pressure (at same volume and temperature). Pressure depends on number of particles not mass of gas.

If pressure does not depend on mass then it cannot be caused by weight.
Solid and liquid have weight, gas does not. Gas pressure is not caused by weight.

Gas pressure is caused by change of momentum


Mass (or weight) of a volume of gas, the number of particles, scales linearly with its pressure assuming the ideal gas law.

The pressure at the bottom of a column of atmosphere scales with the height of the column, i.e. its volume, i.e. its mass. (IIRC Toricelli discovered this; you check it with the column height of liquid pressure gauges.)

Gas has mass, so has weight. Increase of pressure means increase of mass (weight). If you study small deviations from the ideal gas law, pressure is partly caused by the mass of particles, but that is neither here or there.

[tbctd]
torbjorn_b_g_larsson
5 / 5 (12) May 13, 2016
[ctd]

Gas pressure is caused by momentum changes of its particles, which scales with the inverse square root of particle mass, But again that is neither here nor there.

That gas mass and pressure scales together is caused by thermodynamics of a gas of massive particles. That may be the "cause" you are looking for. Look up Maxwell.Boltzmann statistics and above all statistical physics, where ensembles of particles can predict thermodynamic variables.

Why gases works the way they do is an emergent phenomena of classical physics. Asking why gases behaves like gases is like asking why liquids flow. That is the way the universe swings. [/shrug]
torbjorn_b_g_larsson
4.7 / 5 (14) May 13, 2016
"New research from the University of Washington uses bubbles trapped in 2.7 billion-year-old rocks..."

How this "researchers" can be sure that the isotopic clock which use to obtaint the age of this rocks is started form zero?.


Because they are geologists with extensive expertise on dating.

Oh, and obviously as any kid can tell, lava encapsulates the radioactive material as it solidifies, making for a really "solid" clock reset. You can really trust counting remaining radioactive atoms and their daughter products in lava sediments. LOL.

Creationists are crazy, handwaving away kid stuff and experts like both are not obvious. Crazionists? A 'solidified' mind brainwashed to a false claim of nature having invisible bearded garden fairies that grant you 'eternal life' if you wave their magic prayer wand just so? The reader may chose.

[Yes, I removed the troll filter. I have to have my daily laugh. ;-) ]
barakn
1.3 / 5 (15) May 13, 2016
I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.

The atmosphere, like many other things, is weightless. -rojclague
No. The reason you don't feel the air pressure is that your body has an internal pressure that matches the atmospheric pressure. The net force on your skin is zero, as long as you are not moving relative to the local air mass.
bschott
1.3 / 5 (13) May 13, 2016
why gases become plasma at certain T-E-M-P-E-R-A-T-U-R-E-S. These would be nuclear processes affected by temperature.

Do you even know what the term "nuclear" means?
Your are voicing opinions about subjects on which you have no competence whatsoever.
Nobody in his right mind can take your posts seriously.
Consistently nonsensical.


Phys1 voicing his opinions on an aspect of physics he claims to understand:

http://phys.org/n...que.html

Describe the process of creating fusion at room temperature, or at 0 Kelvin

Describe the process of creating a quark/gluon plasma at room temperature.

If the statement that temperature doesn't affect nuclear processes is true, you can do both.

Given your assault on DM theory in that other thread this should be fun.

rojclague
1 / 5 (11) May 13, 2016
I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.

The atmosphere, like many other things, is weightless. -rojclague
No. The reason you don't feel the air pressure is that your body has an internal pressure that matches the atmospheric pressure. The net force on your skin is zero, as long as you are not moving relative to the local air mass.

Internal pressure and incomprehensibility would stop me being squashed. It would not stop me feeling the weight.
We don't feel weight because air does not have weight. Air has pressure acting equally in all directions.
Phys1
4.6 / 5 (9) May 13, 2016
Firstly, the formation of a plasma out of gases atoms does not involve nuclear degrees of freedom. Note that the formation of a quark-gluon plasma obviously does.

If the statement that temperature doesn't affect nuclear processes is true, you can do both.

You actually have a point. Nuclear decay typically involves gamma radiation of 100s of keV, which corresponds to billions of degrees Kelvin. At those temperatures nuclear physics becomes temperature dependent. That was not exactly the temperature range that you suggested when you said, nonsensically, that
gases become plasma at certain T-E-M-P-E-R-A-T-U-R-E-S. These would be nuclear processes affected by temperature.

Ordinary plasmas require temperatures in the range of 100.000 K, unless generated by impact ionisation.
Uncle Ira
2.6 / 5 (35) May 13, 2016
We don't feel weight because air does not have weight. Air has pressure acting equally in all directions.


You win Skippy. That is a distinction that very peoples here earn so quickly, and we got some really, really and one more really, simple minded trolls here. Five postums must be some kind of record.

Oh yeah, I almost forget. If you are ever going to have any real fun here, you might want to consider the "Official-Physorg-Basic-Trolling-101" class. It's free with the double your money back guarantee. The instructor's name is the Reg-Monday-Skippy. (Save your money if he tells you you have to buy a book at the Amazon, it's really lame.) After you finish it, you should probably be able to keep a couyon as dumb as me on the hook for at least 11 or 10 postums.
Phys1
4.6 / 5 (10) May 13, 2016
Uncle Ira says:

"An atom has mass, so in the presence of gravity it has weight."

Astronauts in the ISS have mass and are in the presence of 90% of the surface gravity on Earth. . They are weightless.

"Don't matter if the atom is in a solid, the liquid or the gas, that same atom has the same mass, and in the same gravity field it will have the same weight."

I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.

The atmosphere, like many other things, is weightless.

Mass does not always cause weight. Weight is unusual. It is only caused by mass which is prevented from moving by a solid surface.

Study some physics. Begin with Archimedes (c. 287 BC – c. 212 BC).
Then the Magdeburg hemisphere experiment (1654).
Newton's laws top top it off.
chileastro
2.8 / 5 (20) May 13, 2016
bshit is amazing in a way. Always manages to get everything completely wrong. You'd think that someone like that would sometimes say something correct, getting their wrong statement wrong, but that one is a marvel. Never misses. Always wrong. Few true compasses in this life but if that one says it, it's wrong. Very reassuring. We all thank you.
Manfred Particleboard
1 / 5 (7) May 13, 2016
Still wanting to weigh air? A balance beam with an evacuated sphere on one arm will show the change in density of the surrounding medium. Once it has been zeroed you can watch the change in air pressure (or density) by the movement of the beam.
Phys1
4.6 / 5 (11) May 14, 2016

Internal pressure and incomprehensibility would stop me being squashed.

Is that pun intended? As soon as you are comprehended you will be squashed, like a Schrodinger cat?
rojclague
1 / 5 (10) May 15, 2016
Manfred Particleboard says:

"A balance beam with an evacuated sphere on one arm will show the change in density of the surrounding medium."

A squashed basketball ( or soft plastic beachball) and the ball pumped to 1 atm have the same effect on scales, called weight.

https://www.youtu...tS6-qCJ4

This video claims to show weighing air.If you go to 5:26 he admits the inflated balloon is not always heavier. I admire his honesty. Not all deflated balloons have the same mass.

Air pressure is caused by mass and temperature not weight.
rojclague
1 / 5 (9) May 15, 2016
Phys1 says:

RogerC: Internal pressure and incomprehensibility would stop me being squashed.

phys1:
is that pun intended? As soon as you are comprehended you will be squashed, like a Schrodinger cat? 

II like your comment.
I meant incompressability. But my computer thought it knew better.
To repeat my point,
If I am being squashed from two opposite directions I don't move or shrink but I continue to feel both forces.

Not being compressed is not an explanation of lack of down force from air above my head.
Phys1
4.4 / 5 (7) May 15, 2016
We don't feel weight because air does not have weight. Air has pressure acting equally in all directions.

Under water I don't "feel weight" but we would not say water has no weight.
TehDog
4.6 / 5 (10) May 15, 2016
Take the column of air above your head (say, 1ft^2 by 50 miles), freeze it. Now balance it on your head.
(I'll get me coat...)
Whydening Gyre
4.6 / 5 (9) May 15, 2016
We don't feel weight because air does not have weight. Air has pressure acting equally in all directions.

Under water I don't "feel weight" but we would not say water has no weight.

Ever been hit by a good sized water balloon?
Whydening Gyre
5 / 5 (8) May 15, 2016
If I am being squashed from two opposite directions I don't move or shrink but I continue to feel both forces.

Not being compressed is not an explanation of lack of down force from air above my head.

You don't feel it because you are of a species that evolved at that pressure level. your internal pressure is the same as what is directly outside of you.
Whydening Gyre
5 / 5 (8) May 15, 2016
We don't feel weight because air does not have weight. Air has pressure acting equally in all directions.

It does have weight. It's whatever your current barometric pressure is (depending on the weather). It just so happens that it is also pressing down on ever point surrounding you, therefore equalizing whatever pressure you might be feeling.( Along with your body being porous enough to also realize that same pressure.)
Phys1
4 / 5 (4) May 16, 2016

Not being compressed is not an explanation of lack of down force from air above my head.

You are being compressed. The weight of the air exerts pressure in all directions, so there is a pressure of about 1 kilogram per square centimeter on every bit of your skin, at right angles to the surface. As a consequence you are a fraction of a millimeter shorter than you would be under low pressure conditions.
rojclague
1 / 5 (7) May 16, 2016

Whydening Gyre says:

"your internal pressure is the same as what is directly outside of you."

Blood pressure is about 2psi. That is 1/8 of atmospherics pressure.
What internal body pressure is higher than that?
Phys1
4.4 / 5 (7) May 16, 2016
The blood pressure comes on top of the atmospheric pressure and is counteracted by the elasticity of the vessel walls. Outside the vessels there is atmospheric pressure.
Guy_Underbridge
2.5 / 5 (11) May 16, 2016
Blood pressure is about 2psi. That is 1/8 of atmospherics pressure.
Poke a hole in yourself. If you auto-inflate, then what you've just stated is correct. If not, get a band-aide on your way back to the drawing board.
rojclague
1 / 5 (9) May 16, 2016
Phys1 says:

"The weight of the air exerts pressure in all directions,"

I agree, air pressure is in all directions. So it cannot be caused by weight which is only downward.

Guy_Underbridge says"

Poke a hole in yourself.

RogerC: Only blood at 2psi comes out, not flesh Where is the 15 psi to balance air pressure?

Even if the air pressure is balanced by internal pressure I would still feel it trying to squash me.

Why doesn't weight of air register on my bathroom scales?
Phys1
4.4 / 5 (7) May 16, 2016
Phys1 says:

"The weight of the air exerts pressure in all directions,"

I agree, air pressure is in all directions. So it cannot be caused by weight which is only downward.


That is a non-sequitur. You understand less of liquids and gases then Archimedes did 2250 years ago.
Uncle Ira
2.3 / 5 (33) May 16, 2016
Phys1 says:

"The weight of the air exerts pressure in all directions,"

I agree, air pressure is in all directions. So it cannot be caused by weight which is only downward.


That is a non-sequitur. You understand less of liquids and gases then Archimedes did 2250 years ago.


@ Phys1-Skippy. It is so much worse than that, seriously. He is renown in the U.K. for his climate science skeptical ranting. He is also the big supporter of the U.K. version of the Tea Partying Skippys. And sadly, I have to report to you, he promotes his services as a "private math and science tutor".
Phys1
4.4 / 5 (7) May 17, 2016
I get the picture. And are these his sockpuppets? They seem to follow you around like a flock of puppies.

Estevan57 Whydening Gyre hame hupidinoh wazisezav genegepuci huduz yezi gaku sadu xore jodoyimu cunopure yiyifiso wixekehozu wawasi foros sojari zusomoyux nalo tosu civufatot
Uncle Ira
4.1 / 5 (9) May 17, 2016
I get the picture. And are these his sockpuppets? They seem to follow you around like a flock of puppies.

Estevan57 Whydening Gyre hame hupidinoh wazisezav genegepuci huduz yezi gaku sadu xore jodoyimu cunopure yiyifiso wixekehozu wawasi foros sojari zusomoyux nalo tosu civufatot


Non, that is just my fan club. Estevan-Skippy and Whydening-Skippy are just normal peoples but the all rest of him is just a fan. That's how he let's me know I am doing the good job.
Whydening Gyre
5 / 5 (8) May 17, 2016
I get the picture. And are these his sockpuppets? They seem to follow you around like a flock of puppies.

Estevan57 Whydening Gyre hame hupidinoh wazisezav genegepuci huduz yezi gaku sadu xore jodoyimu cunopure yiyifiso wixekehozu wawasi foros sojari zusomoyux nalo tosu civufatot

@Phys;
Keyboard problems? or some sort of ancient alien language?
Captain Stumpy
4.6 / 5 (9) May 17, 2016
I get the picture. And are these his sockpuppets? They seem to follow you around like a flock of puppies.

Estevan57 Whydening Gyre hame hupidinoh wazisezav genegepuci huduz yezi gaku sadu xore jodoyimu cunopure yiyifiso wixekehozu wawasi foros sojari zusomoyux nalo tosu civufatot
most of those are zephir socks

likely zeph is building a new sock army - just sayin'

PS - to anyone with time on their hands:
1- there is an expansive list of zeph socks in various places validated by various MODS and methods (@whyde- check out the Joint list)

2- there are typical patterns in zeph's use of names that are demonstrably tied to his native language and speech patterns / religious beliefs

Uncle Ira
4.2 / 5 (10) May 17, 2016
likely zeph is building a new sock army - just sayin'


Maybe it is, but maybe not. Nounemon-Skippy got mad at me the other day because I said I did not care about votes and it was silly for him to care about it too. Then he said I would feel different if he set up an automated puppet army to vote me down. I thought maybe it was him. If it is Zephir-Skippy I am not so flattered as if Nounemon-Skippy took the time to do it. Either way, I take it as a sign that I am doing a fine job doing whatever it is I am doing.
Whydening Gyre
4.6 / 5 (9) May 17, 2016
Estevan57 Whydening Gyre hame hupidinoh wazisezav genegepuci huduz yezi gaku sadu xore jodoyimu cunopure yiyifiso wixekehozu wawasi foros sojari zusomoyux nalo tosu civufatot
most of those are zephir socks

likely zeph is building a new sock army - just sayin'

PS - to anyone with time on their hands:
1- there is an expansive list of zeph socks in various places validated by various MODS and methods (@whyde- check out the Joint list)

2- there are typical patterns in zeph's use of names that are demonstrably tied to his native language and speech patterns / religious beliefs

Why does Phys have me on that list?
Captain Stumpy
4 / 5 (8) May 18, 2016
Why does Phys have me on that list?
@Whyde
... it's just the total list of who rated copied and pasted at the moment he posted

i wouldn't worry about it
barakn
1 / 5 (4) Jun 09, 2016
I feel the weight of a brick on my head. I feel the rain falling on my head. I do not feel any effect of the tons of mass of air above my head.

The atmosphere, like many other things, is weightless. -rojclague
No. The reason you don't feel the air pressure is that your body has an internal pressure that matches the atmospheric pressure. The net force on your skin is zero, as long as you are not moving relative to the local air mass.

Don't let the fact that I am right prevent you all from dumping more 1s on me.

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