Long lines. Narrow seats. Baggage fees. You recognize this list. It's the downside of flying on modern commercial airlines. And now we have a new item to add: neutrons.
Spaceweather.com and Earth to Sky Calculus have just completed a 5-continent survey of cosmic ray neutrons at aviation altitudes. From Dec. 2018 through Feb. 2019, Hervey Allen of the University of Oregon's Network Startup Resource Center carried Earth to Sky radiation sensors including neutron bubble chambers onboard commercial flights from North America to Europe, Africa, South America and Asia. Neutrons from deep space were detected on every flight.
Hervey logged 83 hours in the air as he traveled 41,500 miles above 30,000 feet. For reference, that's almost twice the circumference of the Earth. The entire time, he gathered data on X-rays, gamma-rays and neutrons in an energy range (10 keV to 20 MeV) similar to that of medical radiology devices and "killer electrons" from the Van Allen Radiation Belts.
The results were eye-opening. During the trip, Hervey recorded 230 uGy (microGrays) of cosmic radiation. That's about the same as 23 panoramic dental x-rays or two and a half chest X-rays. Moreover, 41% of the dose came in the form of neutrons. This confirms that cosmic-ray neutrons are abundant at aviation altitudes and must be considered in any discussion of "Rads on a Plane."
https://spaceweatherarchive.com/2019/03/12/neutrons-detected-on-commercial-airplane-flights/
(Score: 3, Informative) by Anonymous Coward on Friday March 15 2019, @06:36AM (5 children)
A guy's hand up your ass.
(Score: 3, Funny) by krishnoid on Friday March 15 2019, @06:56AM (4 children)
That's just to insert the dosimeter. For your safety, of course.
(Score: 1, Funny) by Anonymous Coward on Friday March 15 2019, @07:10AM (3 children)
Was there not a graphic file of this floating about the intertubes? Ah, yes! Here it is! [blogspot.com] Ionizing radiation is no one's friend, and copping a feel is not nice, either. Why do you think all those TSA agents kept showing up when they were not getting paid? Yep, it was the live-action molestation. Now with neutrons! It feels so much better, when they feel my balls, to know it is all "scientific".
(Score: 3, Touché) by DannyB on Friday March 15 2019, @02:35PM (2 children)
A free testicular cancer exam as part of TSA's service. TSA is your fiend. Trust the TSA.
To transfer files: right-click on file, pick Copy. Unplug mouse, plug mouse into other computer. Right-click, paste.
(Score: 2) by krishnoid on Friday March 15 2019, @07:38PM (1 child)
"I'm sorry, we have to perform this exam on *all* fliers selected for enhanced screening. If you do not present them for our inspection, ma'am, we will require that customs impound you until we can locate and inspect them."
"Oh, uh ... I left them at home. They're ... on my dog!"
"Dog ... dog ... ok, you're clear. Have a good flight."
(Score: 5, Funny) by DannyB on Friday March 15 2019, @08:56PM
Since nobody is allowed to make Trump jokes any longer . . . I'll pick on the other party . . .
Hillary says: okay, here they are. See that! Mine are bigger than the president's.
To transfer files: right-click on file, pick Copy. Unplug mouse, plug mouse into other computer. Right-click, paste.
(Score: 2) by isostatic on Friday March 15 2019, @08:03AM (2 children)
Neutrons on a plane! I bet there’s protons too.
https://youtu.be/DqgvHUg_vxY [youtu.be]
Atoms! Six of them! Take him away
(Score: 2) by DannyB on Friday March 15 2019, @02:38PM (1 child)
In the helpful spirit of homeopathy, anti-vaxxers, flat earthers and climate change deniers, let me offer the helpful tip that you can protect yourself from those stray protons by using a cloth mask that has been dipped in lemon juice.
Its True! I read it on the intarwebs! A video even proves it is true!
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(Score: 0) by Anonymous Coward on Friday March 15 2019, @04:13PM
I think you misspelled chloroform.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @08:18AM
"I have had it with these motherhugging neutrons on this motherhugging plane!"
(Score: 0) by Anonymous Coward on Friday March 15 2019, @09:03AM (33 children)
I wonder if the increased neutron flux is triggering bugs in the airplane software. Thasts why there's so many crashes near the equator recently.
(Score: 5, Funny) by shrewdsheep on Friday March 15 2019, @09:42AM (32 children)
You have it quite backwards. The neutrons come in, due to global warming they have expanded in recent years, removing space available to electrons (that's the software, you know). This makes computers calculate slower of course (that's why computers are always slower than advertised) leading to all sorts of consequences. The solar minimum is a distant second if not third in this game.
(Score: 2) by aiwarrior on Friday March 15 2019, @10:35AM (3 children)
Dang! Are you a Markov Chain Generator with some semantics filtering so that the topics seem slightly related? They definitely would pass the Turing test with a layman on the other side.
(Score: 2) by coolgopher on Friday March 15 2019, @11:29AM (2 children)
More like a Markov pyramid of needs. I mean, just about everything is made up of stuff needing neutrons, right? Gotta be one of the lower pyramid levels!
(Score: 2, Informative) by Anonymous Coward on Friday March 15 2019, @12:11PM (1 child)
No, most of the universe is made of hydrogen-1, which doesn't have any neutrons.
https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements [wikipedia.org]
https://en.wikipedia.org/wiki/Isotopes_of_hydrogen [wikipedia.org]
(Score: 2) by nitehawk214 on Friday March 15 2019, @12:47PM
That's a good point. If anything we don't have enough neutrons to waste on radiation. Get those free neutrons into deuterium, stat!
"Don't you ever miss the days when you used to be nostalgic?" -Loiosh
(Score: 2) by theluggage on Friday March 15 2019, @01:25PM (26 children)
Nonsense. Neutrons are harmless - nearly half your weight is made up of neutrons, and they don't carry any electrical charge so how can they hurt you? Its like all those silly people worrying about carbon dioxide, which animals have been breathing out since 4004BC, and is so safe that they put it in lemonade. Meanwhile, they're recklessly fitting WiFi in planes that emits electromagnetic radiation...
Wait... what's that... neutrons are also a kind of radiation!? ...you say there are neutron bombs!? Oh my God, something must be done! Won't someone think of the children?
(Has anybody tried starting the rumour that carbon dioxide is a by-product of making alcoholic liquor? - might be a bit of a zero-sum game, that one)
(Score: 0) by Anonymous Coward on Friday March 15 2019, @01:40PM
These are "albedo neutrons": https://www.jhuapl.edu/techdigest/views/pdfs/V03_N4_1964/V3_N4_1964_Williams.pdf [jhuapl.edu]
They do the opposite of CO2.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @02:02PM (1 child)
wait I thought it was 4019BC. Every year, the counter increments because it's always been 6000 years since creation.
(Score: 2) by AthanasiusKircher on Friday March 15 2019, @04:16PM
I guess you don't realize that it's 2019+4019-1=6037 years since 4019 BCE.
(Score: 5, Informative) by Immerman on Friday March 15 2019, @02:09PM (22 children)
You're being funny, but you're also advancing one of the great misunderstandings about CO2. Generally speaking ecological CO2 such as produced when breathing, burning wood, or brewing alcohol isn't a problem - the planet has a nice relatively stable ecological carbon cycle that circulates carbon between CO2 and various hydrocarbons like wood and flesh, so that the total amount of CO2 remains relatively constant.
When you slash-and-burn large areas of forest, that's a problem because you upset the balance - releasing all that carbon as CO2, and then using the land for farming or urbanization that store far less CO2 per acre, so that the total amount of free CO2 in the system increases. But so long as you're not disrupting the ecological balance that way, you pretty much don't have to worry about disrupting the CO2 balance.
The problem is when you burn *fossil* carbon fuels - then you're taking carbon that was mostly geologically sequestered 100's of millions of years ago - in the case of coal, during the ~80 million years between when wood evolved, and when mold, etc. figured out to eat it, a period that diverted our planet from a slowly building runaway greenhouse process that would have likely otherwise ended with Earth looking much more similar to Venus. These days, with mold eating pretty much everything and re-releasing the CO2, the geological carbon cycle is vastly slower, and can only sequester a fraction of the carbon released by human use of fossil fuels, so the total amount of CO2 in the atmosphere increases. In theory the amount of biomass could grow to absorb it, but we don't see that happening.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @02:24PM (19 children)
And where would the 4.8e20/5.15e18 ~93x more mass come from to do this?
You need to get 4.75e20 kg of stuff to put in that atmosphere from somewhere. Equivalent to evaporating ~ 1/3 of Earth's oceans.
https://en.wikipedia.org/wiki/Atmosphere_of_Venus [wikipedia.org]
https://en.wikipedia.org/wiki/Atmosphere_of_Earth [wikipedia.org]
https://en.wikipedia.org/wiki/Ocean [wikipedia.org]
(Score: 0) by Anonymous Coward on Friday March 15 2019, @02:33PM (6 children)
It takes ~336,000 J/kg to evaporate water. So this process would require 1.6e26 J, or about half the entire output of the sun.
https://en.wikipedia.org/wiki/Orders_of_magnitude_(energy) [wikipedia.org]
(Score: 2) by Immerman on Friday March 15 2019, @03:07PM (5 children)
Double check that table - that's half the output of the sun in *one second*
Meanwhile the Earth intercepts about 4.6*10^-10 of the sun's total output
So, to receive that much power would require 1.6e26 J * 2 * 4.6*10^-10 = ~ 37*10^15 seconds, or about 1 billion years - less than 1/4 of the age of the Earth.
We wouldn't be there yet, but we would likely be well past the point where complex life could thrive on the surface.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @03:16PM (4 children)
I get:
secPerYear = (60*60*24*365) = 31,536,000
(1.6e26 * 2 * 4.6e-10)/31536000 = 4.67 billion years
(Score: 2) by Immerman on Friday March 15 2019, @04:04PM (3 children)
Quite so. I went back and added the two that I had forgotten, and then adjusted the result in the wrong direction. Except, actually it was the *right* direction (increasing the power decreases time needed to to receive X energy) , and the rest of my math was completely wrong. Too early for math I guess. Really need to remember to always put in my units and make sure they cancel properly for sanity checking
So, the proper calculation should be:
time needed = total energy needed / power influx:
so 1.6e26 J (energy needed to vaporize ocean) / 1.7e17 J/s (total solar power hitting Earth, from the table) = 941e6 seconds = 29 years
Which is also a lot closer to my original expectations.
So, pile on enough greenhouse-effect insulation, and it would take less than a century to *completely* vaporize the Earth's oceans.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @04:37PM (2 children)
Yes, that matches with the "Total energy from the Sun that strikes the face of the Earth each year" I see there now.
I hadn't thought of this before. So there is an observable drop in the amount of radiation leaving the earth when viewed from space? I.e., earth would actually appear cooler when measured remotely?
(Score: 2) by Immerman on Friday March 15 2019, @04:56PM (1 child)
Well, it depends on exactly what you're asking.
So long as a planet is in thermal equilibrium (i.e. not currently heating or cooling) it will always emit *exactly* 100% as much average energy as it's receiving from the sun. Any less, and that excess energy must be accumulating on the planet, causing warming.
If instead you're talking about the current situation, then yes - the increase in greenhouse gasses will make the planet look slightly dimmer, until such time as the planet warms enough to once again be able to radiate energy as fast as it's coming in.
(Score: 2) by Immerman on Friday March 15 2019, @04:59PM
It's worth mentioning that at the current thermal discrepency though the imbalance in received versus radiated light is *tiny* - it's only the truly mind-boggling absolute amount of solar energy hitting the Earth that allows a tiny imbalance to cause as much heating as we're seeing.
(Score: 4, Informative) by Immerman on Friday March 15 2019, @02:55PM (11 children)
Funny thing about water - it doesn't stop evaporating until you either lower the temperature or saturate the atmosphere. And water is a potent greenhouse gas, the more water there is in the atmosphere, the higher the temperature climbs, and the more water is required to saturate it.
Water alone is self-limiting in that runaway process, since the increase in temperature from adding 1 unit of water to the atmosphere is insufficient to increase the saturation point by one full unit worth of water - so the humidity increases, and precipitation becomes more likely. CO2 doesn't have that problem though - it just increases the temperature, which causes more water to evaporate just to maintain the same percent humidity. At the current temperature (14C average) , increasing the atmospheric temperature by only 1*C increases the amount of water the atmosphere can hold by at the same %humidity by almost 7%. Which means about 7% more greenhouse gasses in the atmosphere. Which, since water is the primary greenhouse gas, likely means somewhere around an 7% increase in the total greenhouse warming (which is currently somewhere around 32C), or an additional 2.2C. And as temperatures increase the effect gets more dramatic - at 20C the water content increases by 9% per degree, and the effect just keeps getting larger the hotter it gets.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @03:23PM (7 children)
The energy to evaporate the water will also increase as the pressure rises. At Venus pressures water doesn't boil until 300 C:
https://www.engineeringtoolbox.com/boiling-point-water-d_926.html [engineeringtoolbox.com]
(Score: 2) by Immerman on Friday March 15 2019, @03:52PM (6 children)
Evaporation doesn't rely on boiling, and happens at pretty much any temperature. It accelerates as you approach boiling, and slowing it will reduce the equilibrium humidity somewhat, but it's not going to fundamentally alter the process.
Especially if we're only talking 2atm instead of Venus's 90atm. Assuming vaporization was the primary cause of atmospheric pressure increase, we'd be talking about ~103% of the current atmospheric mass being water, instead of 3%. So about 33x the amount of greenhouse gasses. That might not be truly Venus-like, but it'd be close enough that we couldn't survive.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @04:07PM (5 children)
If you want Temperatures like Venus you need pressures like Venus (even higher since Earth is farther from the sun). You can find ~1.5 atm down some mineshafts and see the temperature already rises 42 K:
http://nopr.niscair.res.in/bitstream/123456789/2506/1/IJRSP%2037%281%29%2064-67.pdf [niscair.res.in]
(Score: 2) by Immerman on Friday March 15 2019, @04:24PM (2 children)
I don't want temperatures like Venus - temperatures too high to support complex life are quite sufficient for us to be "Venus-like" enough for me.
(Score: 0) by Anonymous Coward on Friday March 15 2019, @04:33PM (1 child)
Which is what temperature? The moon goes up to nearly 400 K, so if you aren't worried about the pressure aspect then I would say you are thinking more of a "moon-like" than "venus-like" situation.
https://www.sciencedirect.com/science/article/pii/S0019103516304869 [sciencedirect.com]
(Score: 2) by Immerman on Friday March 15 2019, @04:47PM
Peak temperatures are rather irrelevant, you can always find somewhere to hide. And the Moon's average temperature varies between 215K at the equator, to 104K above 85* latitude.
Meanwhile the Earth's average is currently 287K, and only has to increase by 86C to make it awful difficult to find liquid water on the surface (well, a bit more to compensate for increased pressure, but even increasing it to 10atm only increases the boiling point by about 70C, we don't have to get anywhere near Venus's average of 735K to make life as we know it impossible.
(Score: 1) by khallow on Friday March 15 2019, @05:55PM (1 child)
Because the Earth is warm. From your article:
(Score: 1) by khallow on Friday March 15 2019, @05:56PM
(Score: 2) by HiThere on Friday March 15 2019, @04:59PM (2 children)
I think you left out black body radiation. As the temperature of the earth increases, the amount of heat it radiates increases. IIRC this is a fourth power law. So it should mean you are overestimating the rise in temperature. (By how much, though?)
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by Immerman on Friday March 15 2019, @05:21PM (1 child)
Not really - that's doesn't factor into things as much until you start looking at the *consequences* of the increased greenhouse gasses. If you increase the planet's temperature by 1*C, you increase the water in the atmosphere by somewhere around 7% to maintain equilibrium humidity.
Now, the consequences of increasing the amount of greenhouse gasses by 7% get more complicated - they make the atmosphere less transparent to IR (the frequency at which something the Earth's temperature radiates most black-body radiation), which means that the Earth must get warmer in order to radiate enough energy to restore equilibrium with the incoming solar radiation (very little of which is IR, because the sun is hot enough to radiate primarily in the visible spectrum)
Figuring out how much additional warming must occur to reach that new thermal equilibrium is where the black black-body formula comes into play, and means (along with other non-linearities) that the 7% increase in greenhouse gasses won't cause a full 7% increase in greenhouse warming (currently estimated at around 36C total, based on the discrepancy between measured and theoretical temperatures of something with the Earth's albedo). A simple linear extrapolation would expect that 7% increase in water to cause a about 2.5C of further warming.
However, there's also the fact that that increased warming will put even *more* water into the air to maintain stable humidity. Even if the actual temperature change associated with that 7% increase is only half the linear prediction, 1.25C, that still means you're going to further increase the amount of water in the air by another ~9% to maintain the same humidity. (and of course, that 9% will cause even more warming, which will cause even more evaporation...)
Meanwhile, at Earth's average temperature of about 288K, a 1C increase will only increase the black-body radiation by about (289/288)^4 -1 = 1.4%. If a 7% increase in greenhouse gas mapped directly to a 7% decrease in the transparency of the atmosphere to IR, you would need to increase the temperature to around 293K, a 5C difference, in order to restore energy equilibrium.
(Score: 2) by HiThere on Friday March 15 2019, @07:47PM
Thank you. I couldn't have even estimated that.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by krishnoid on Friday March 15 2019, @07:45PM
Well, that would require the plant populations to increase significantly, in conditions that support that growth -- perhaps contained in something like a large structure that lets in sunlight and keeps moisture in, like large panes of glass would. Now that I think about it, that is kind of a fanciful conception, though.
(Score: 2) by theluggage on Friday March 15 2019, @07:47PM
Quite right - I probably should have included <sarcasm> tags and a link to the Wikipedia entry for "parody" but then this is SoylentNews, not Tw@tbook so I have higher expectations of the readership.
(Score: 2) by Freeman on Friday March 15 2019, @03:34PM
Don't blame the universe for Badvertisements.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 5, Informative) by Immerman on Friday March 15 2019, @01:42PM (8 children)
Just to correct the summary, the neutrons are obviously NOT cosmic rays. Free neutrons have a half life of only about 10 minutes before decaying into hydrogen, and reach energies above 20MeV when traveling at relativistic velocities that would slow their local time significantly. Therefore, these neutrons can't possibly have originated from outside the solar system.
Instead, they almost certainly originate in the atmosphere, as part of the high-energy particle cascade created when a cosmic ray smashes into an air molecule. It's created by cosmic rays, but isn't actually a cosmic ray itself.
(Score: 2) by PiMuNu on Friday March 15 2019, @04:47PM (7 children)
> NOT cosmic rays
Most particle physicists refer to cosmic rays but they really mean secondary particles induced by cosmic rays. For example, at sea level, away from any radioactive or artificial radiation sources, the majority of incident particles are muons (half life 2.2e-6 seconds) created by pion cascades of protons striking the upper atmosphere. However, if asked what the noise in my detector is, I would happily answer "oh its cosmic rays". And everyone would know what I meant.
You are being a bit too pedantic.
(Score: 5, Insightful) by Immerman on Friday March 15 2019, @04:50PM (6 children)
I didn't realize that SN was populated primarily by particle physicists.
Experts take all sorts of linguistic short-cuts when talking amongst themselves. When talking to laymen however, it's important to not do that or you just spread confusion and misinformation.
(Score: 1, Flamebait) by PiMuNu on Friday March 15 2019, @05:03PM (5 children)
Sorry for confusing all you laymen. I think it's pretty obvious what is meant however, even to people so uninformed as SN readers.
(Score: 2) by TrentDavey on Friday March 15 2019, @05:24PM (1 child)
I didn't really understand the original since I thought neutrons didn't interact with much and I thought cosmic rays were solar system source gamma rays and I'm a physics lab demonstrator. It never hurts to form your responses with people in mind who don't travel in the same circles as you do. Otherwise, how are others to understand and learn? Kinda of a Catch-22.
(Score: 3, Informative) by Immerman on Friday March 15 2019, @05:46PM
Well, if you're a demonstrator these details may come up at some point, so let me correct you a bit:
You're right about neutrons not interacting much, they pretty much have to collide head-on with the infinitesimally small nucleus of an atom to interact at all. So, once they're produced they tend to travel in a straight line until they either hit something very dense (like lead, or fission fuel), where the odds of a nucleus being directly in their path are high, or until they decay into a proton and electron after an average of about 14.4 minutes (average_life = sqrt(2)*half_life)
Cosmic rays though are high-energy particle radiation (mostly protons and atomic nuclei, often traveling at relativistic velocities) primarily originating outside the solar system (hence "cosmic"), that are believed to mostly originate from supernovas.
Gamma rays in contrast are photons high-energy electromagnetic radiation that originate primarily from nuclear reactions and decays of any type. Space is full of those *too*, since any gamma ray that escapes a star will keep traveling just like the visible light does, but they don't really have anything to do with cosmic rays. Those with an extra-solar origin tend to come from neutron stars, pulsars, supernovae, and other ultra-hot objects that trigger extreme levels of nuclear reactions near their surface where the photons can escape easily.
(Score: 3, Insightful) by Immerman on Friday March 15 2019, @05:30PM (2 children)
Really? You think most SN readers are aware that the half-life of a neutron is such that such low-energy neutron radiation couldn't possibly be cosmic rays and must be secondary radiation?
Now, we have a bunch of clever people here, that's a big part of the reason I take part in the discussions. But there's still a limit to how much random science trivia any one person can hold in their head. Based on my conversations, I really doubt more than maybe 10-20% of Soylentils are well versed enough in nuclear physics to spot the error.
(Score: 0) by Anonymous Coward on Saturday March 16 2019, @03:34AM
I studied astrophysics for my BS and I did not know that answer. Seriously wtf?
(Score: 2) by PiMuNu on Monday March 18 2019, @09:34AM
Sorry I shouldnt have been sarcastic.