Thursday, October 02, 2014

Detect cosmic rays with your Android device

The camera-based app is called DECO
Sad, off-topic: Martin Perl died: a Stanford Nobel prize winner for the tau lepton discovery...

If you detect this pattern, then FBI is trying to irradiate you by lethal radiation. You may only find out if NSA hasn't hacked your smartphone's camera, however. ;-) More seriously, the app detects both cosmic rays and radioactivity from the environment.

If you have an Android device, you are invited to download an app by Justin Vandenbroucke who is junior faculty in Wisconsin:
Univ. at Madison: press release
Their astroparticle center about DECO

App part 1 (data logger), app part 2 (DECO app)
You may need to change your Android settings to allow the installation of APK packages from outside Google Play – you must think twice whether you trust apps linked to from a page.

Both parts of the app are smaller than 1 megabyte.

Your Android camera normally detects visible light but it's sensitive to other things, too. In particular, if you cover it so that it should be black, it is still not black.

Instead, it will still detect some noise and that includes the cosmic rays. And the app, after it records the signal each second or so, may analyze what it sees by methods that are not too different from the methods employed by astroparticle experimenters.

The author of the app hopes that this app or its future cousins will energize some kind of "citizen science". You may imagine millions of people who are detecting cosmic rays all over the Earth. You could use such Android users instead of detectors in particle accelerators, too. You save $1 billion and just ask the 3,000 ATLAS employees with their Android smartphones to stand somewhere at the collision point. ;-)

A typical screenshot of the DECO app.

If a new Higgs boson or a supersymmetric particle decides to escape from CERN, not die in time, and create a signal in your Android device, let me know! ;-) Just kidding.

The iOS version is work in progress.

P.S.: the second part of the DECO app just crash for me all the time, won't start on my tablet. At least, there may be some Geiger-Müller counters on the Play Store and perhaps some of them are even serious. ;-) I suspect that this app shows rubbish numbers unless you actually connect a special gadget using the microphone cable.


  1. Why doesn't the astroparticle center just ring up the NSA and get the stats straight from the horse's mouth?

  2. Oddly enough, this is the first time I have seen the argument about heat going into the ocean not being able to come back because of the second law of thermodynamics. It occurred to me immediately when I heard of Trenbreths (sp?) argument.

  3. Nice post, Lubos, your two paragraphs on the ocean and the second law of thermo totally demolish all the current talk about “evil heat in the ocean is going to get us”. I sure wish more physicists of your calibre would speak out on this climate nonsense, but it appears the power of funding is too much for that.

  4. Rahmsdorf, Germany’s top climate professional, has been skewered by Tom Moriarty on his blog, a particularly amusing highlight being a line fit to looping data:

  5. Good for us. ;-) Just to be sure, we're not the only two people who noticed this conflict with the second law. Search for "thermodynamics" e.g. on Judith Curry's website, e.g. at

  6. Judith Curry pointed out the entropy effect too:

    “All in all, I don’t see a very convincing case for deep ocean sequestration of heat. And even if the heat from surface heating of the ocean did make it into the deep ocean, presumably the only way for this to happen involves mixing (rather than adiabatic processes), so it is very difficult to imagine how this heat could reappear at the surface in light of the 2nd law of thermodynamics.”

    If you tell this to greenie activists, online, they call you stupid for watching Fox News.

  7. One of the first lessons a chemist gets used to thinking in is enthalpy, with both an energy term and a temperature dependent entropy term, so that's plenty more science majors who appreciate entropy effects. Many reactions even are controlled in outcome by it.

  8. Thanks, Bill! I hope that this is just a draft app and he or someone else will produce something more comprehensive and accurate.

  9. John F. HultquistOct 2, 2014, 7:34:00 PM

    The second law of thermodynamics is not something I can say to most of the people I know and expect them to understand. So I have to say something else.

    There is a small irrigation ditch running through my property. A down-ditch neighbor calls and says she needs some boiling water for tea.
    So I boil a pot of water and pour it in the ditch, then tell her to take it out when it gets there.

    That’s not going to work.
    Is it?

  10. It is an excellent popularization of the second law. ;-)

  11. I'd like to see more about the positive benefits of anthropogenic global warming. Bjorn Lomborg wrote about the reduction in deaths by freezing (>> deaths by heating), and it is occasionally mentioned in the press that CO2 is a kind of fertilizer which makes plants grow bigger and faster. Doesn't that imply a future increase in total agricultural yield to feed a starving planet?

    But the benefit I almost never see mentioned is how much larger the temperate zone would become if the earth warmed a few degrees. Just look at the globe. There are vast regions in Canada and the northern reaches of Eurasia that are now steppe and tundra, and it is precisely these latitudes that most the warming is expected to occur. A larger temperate zone means a more inhabitable planet in most people's minds.

  12. The "preindustrial temperature" ? Actually our current warming (such as it is) began at the bottom (the low temperature) of the LIttle Ice Age which would be in the mid 1600s, so there was two centuries of warming BEFOREHAND the industrial revolution. Most of the warming had to be natural variation.

    And that 2 degree ceiling would be based on WHAT preindustrial temperature?

  13. If you tell this to greenie activists, online, they call you stupid for watching Fox News.

    People like this don't even have to be greenie activists, and they don't always mention Fox News. Here's a line I've heard two or three times: "You're not a scientist. You can't possibly know all the ways the heat could come out of the ocean. Not even scientists know them all, probably.'

  14. So far my phone has detected 3 Higgses!!!😑😨

  15. Another point that is usually overlooked is that a one kelvin increase in the average global temperature (neglecting geographic and temporal fluctuations) could never result in a uniform one kelvin increase everywhere. This is because heat transfer increases rapidly with temperature.
    Radiative heat loss, which dominates, varies as the fourth power of absolute temperature. Taking the temperature derivative, it is obvious that a given increase in steady-state heat input in any location will result in a temperature increase that varies as the negative third power of the absolute temperature in that location. Really hot places, such as Baghdad in summertime, will see only about one third as much increase as a location initially at -40 Celsius.
    The cold steppes and tundra will benefit much more than the hot places are harmed by added heat loading.

  16. I have yet to find any publication or paper that explains in detail exactly where or how the 1c or 2c will manifest itself.

    Will the earth be hotter by that much everyday?
    Will it be shown in the highest temps recorded each day at each station? Or will it show itself at night keeping the nighttime slightly warmer?
    Perhaps the 1c or 2c will make the entire day warmer?

    Does anyone know?

  17. I see nothing. I knew it. There are no gamma rays. The Earth is flat.

  18. Keep on working, we need five! ;-)

  19. Perfect! I will use this the next time I teach thermodynamics (along with my usual discussion as to why running the microwave oven in reverse won't uncook my dinner).

  20. Dear Bill, haha, you could even present this piece of didactics in practice. Imagine the shock of the undergraduate students: our professor Zajc, the department chief, spilled hot coffee on me screaming Now you understand the second law! ;-)

  21. "ask the 3,000 ATLAS employees with their Android smartphones to stand somewhere at the collision point."

    That is silly. Put one in each hand and fire 1500 of them after confiscating their hardware for National Security reasons.

  22. Dear Lubos: I stepped down as Department Chair in July, and am gradually and happily returning to being a 'real' physicist. I think I will avoid your suggested lecture demonstration, based on this famous precedent's_Restaurants

    here in the U.S. ;-)

  23. A nice backwards move, Bill.

    I didn't know about the precedent but the common law remains mostly puzzling to me.

    Such a hot coffee accident may occur and it's unfortunate if it does (and the restaurant's image may suffer) but a hot coffee is supposed to be hot and if there had been no codified rule how hot it should be, the restaurant - in my understanding of justice - just couldn't have violated any law, and it already had alibi for everything that happened when the lady manipulated the coffee, it was already out of the game.

  24. I notice that Steve Koonin has wandered off the climate alarmist reservation. He's actually a very bright guy. I've seen him work on federal advisory committees, where he can usually bring the others around to seeing things his way. He used to be active in ICF back in the day.

    Meanwhile, a German "climate advisor," with the appropriately Teutonic name Hans Joachim Schellnhuber has dared to criticize the Australians for burning too much coal! His picture accompanies the article below posing as the apotheosis of smugness. These are the same Germans, mind you, who are shutting down their nuclear plants and building dirty lignite-fired plants hand over fist to replace them, and whose CO2 emissions went up 1.5% last year as a result, even as the Australians reduced theirs by 0.8%!

  25. maybe one can detect Ebola with an android ?
    let me take a whack at it.
    In Dunnigan's "Dirty little Secrets" on page 75 it mentions using laser based devices to detect poison gas at a distance. Bingo. That is the sort of thing we want for detecting and screening for Ebola. But we want to look for a different bunch of molecules and not at great distances - more like a few feet, so we don't need powerful lasers. The gist is to get those who know laser detection together with those who know what kinds of molecules indicate an ebola infection, and figure out how to detect low levels of these molecules, and get ideas on how to make the least expensive device to do it - and hand it out to Doctors Without Borders - so they have something better than a simple infrared thermometer. Seems like the sort of thing Bill Gates might be
    interested in having developed - or maybe Hewlett Packard already knows how to do it. One wants an 'ebola-intensity' readout, like taking a temperature.
    Maybe some crowd sourcing/funding. Or maybe some folks with the relevant expertise. Or maybe something like StackExchange to refine things.
    if there is a general methodology - extend it to enterovirus ... etc etc

    'fideous' provided a link at cns (thanks) re Marlan Orvil Scully
    who wrote 'Quantum Optics' and 'Laser Physics' - and got his PHD from Willis Lamb !!
    It does not get any better than that.

    Detects Anthrax in a TENTH OF A SECOND !

    and more details on detecting viruses:

    and about testing Ebola tests and problems with it.

    Coherent Anti-Stokes Raman Scattering !!!
    and shrink this puppy down to a hand held size.

  26. This App Turns my Phone Into A Cosmic Ray Detector to detect some of the super-rare particles that shower down on the Earth when a high-energy cosmic ... It's supposed to be available for Apple and Windows devices.
    Hire iPhone developers