Follow Slashdot stories on Twitter

 



Forgot your password?
typodupeerror
×
Space NASA

Terrestrial Gamma Ray Bursts Very Common 70

Rambo Tribble writes It was long thought that gamma ray bursts were the exclusive province of deep space sources. More recently it was found that storms could produce such emissions, but such occurrences were thought rare. Now, data from NASA's Fermi satellite suggest such events happen over a thousand times a day. Per Prof. Joseph Dwyer, from the University of New Hampshire, "These are big, monster bursts of gamma rays, and one would think these must be monster storms producing them. But that's not the case. Even boring-looking, garden-variety, little storms can produce these."
This discussion has been archived. No new comments can be posted.

Terrestrial Gamma Ray Bursts Very Common

Comments Filter:
  • "These are big, monster bursts of gamma rays, and one would think these must be monster storms producing them. But that's not the case. Even boring-looking, garden-variety, little storms can produce these."

    When they get angry, they can become hulking MONSTER storms

    • The parent post is an Abomination. You should be a Leader and not Ravage this message board with your... uh... Doc Samson?
      • I'm glad someone here is willing to start Harpying to remind us that A-Bombs aren't the only source of gamma rays, and that Thunderbolts* are more common.

        *Spoiler alert. Who is the Red Hulk?
  • by erice ( 13380 ) on Thursday December 18, 2014 @01:07AM (#48623705) Homepage

    Unfortunately, TFA doesn't suggest the question. Gamma bursts were not expected on Earth because they are created by nuclear interactions. Common for stars and other cosmic objects but not expected in thunderstorms. The source could be electrical, which means they are technically x-rays but at a higher energy then thought possible. Alternatively, there is significant nuclear fusion going on in those storms.

    • by Khyber ( 864651 ) <techkitsune@gmail.com> on Thursday December 18, 2014 @01:19AM (#48623747) Homepage Journal

      Uhhh, have you paid attention to the news lately? Lightning bolts are now known to create anti-matter. To produce a gamma ray is pretty much EXPECTED.

      • by jasno ( 124830 ) on Thursday December 18, 2014 @01:54AM (#48623817) Journal

        Wow, you're right!

        http://www.nasa.gov/mission_pa... [nasa.gov]

      • by Anonymous Coward

        From what I read on that nasa.gov link below, the antimatter is created by the gamma ray burst in the thunderstorm. So using the antimatter as an explanation for where the gamma ray bursts come from might not be possible.

        • by Anonymous Coward
          When antimatter and matter combine, you typically get a bunch of gamma rays, especially with low energy positrons. This produces a distinctive 511 keV gamma rays which is how they detected the positrons in the first place. Converting gamma rays into positrons usually requires much higher energy gamma rays on the order of several MeV before you get a decent conversion rate (in theory, a 1.022 MeV gamma ray can produce a positron-electron pair, but it is not going to happen and the chances of it converting
    • Gamma rays are produced by many processes, not only nuclear fusion.

      In this case they are very likely produced by simple ionization of gases and extreme acceleration of electrons. So, yes it is electric.

      The distinction between X-Rays and gamma rays is not the way how they are produced but the energy level.

      It is the same type of interaction like high atmosphere gamma rays that are produced by very high energetic solar wind particles.

      • by radtea ( 464814 )

        The distinction between X-Rays and gamma rays is not the way how they are produced but the energy level.

        As others have pointed out, this is false. Here's a simple guide to the complex language of electromagnetic radiation:

        1) If it was produced by an atomic process it's an x-ray, no matter what the energy.

        2) If it was produced by a nuclear process, it's a gamma-ray, no matter what the energy

        3) If the source is neither atomic nor nuclear, or unknown, it's field-dependent and circumstance dependent. I tend to think of bremstrahlung as gamma radiation unless I'm talking about x-ray sources for imaging or medical

        • Sorry, your explanaitions are all wrong.

          http://en.wikipedia.org/wiki/G... [wikipedia.org]

          Gamma rays are of magnitudes higher energy than x-rays.

          The process how either of both is created is irrelevant.

    • The source could be electrical, which means they are technically x-rays but at a higher energy then thought possible.

      What? The difference between x-rays and gamma rays is not how they're produced but solely their wavelength (or photon energy, which is just another way of stating the same thing). If the wavelength is below 10 picometers (photon energy above 100 keV), it's a gamma ray, regardless of how it's been created.

      • Re: (Score:3, Informative)

        by Anonymous Coward

        If the wavelength is below 10 picometers (photon energy above 100 keV), it's a gamma ray, regardless of how it's been created.

        This varies from flat out wrong to just horrible simplification depending on what field's literature you're looking at. The distinction is arbitrary in the sense that different fields will draw the line where convenient, which includes depending on how it is detected or in many places still distinguishing gamma rays from x-rays by the creation process, even if there is overlap in energy ranges. Astronomy and plasma physics tend to draw arbitrary lines (and not necessarily right at 10 pm... more often some

    • Low-energy nuclear reactions - a crazy idea that won't go away.

    • Unfortunately, TFA doesn't suggest the question. Gamma bursts were not expected on Earth because they are created by nuclear interactions. Common for stars and other cosmic objects but not expected in thunderstorms. The source could be electrical, which means they are technically x-rays but at a higher energy then thought possible. Alternatively, there is significant nuclear fusion going on in those storms.

      Actually gamma-rays are very common on earth. In fact, a common geophysical method of exploration called airborne gamma-ray spectrometry (sometimes called radiometrics) [radiometricsurveys.com] is widely used for regional mapping and mineral exploration. One of the corrections applied to this data is the removal of the cosmic component. The cosmic gamma-rays have greater energies than those from the decay of naturally occurring potassium, uranium, and thorium in rocks and soil.

      The article just says gamma bursts, but they must mean

  • by cachimaster ( 127194 ) on Thursday December 18, 2014 @02:37AM (#48623899)

    Xrays produced by the Bremsstrahlung effect are proportional to the voltage of free-electrons hitting an atom. That is, a 30kV electron would produce X-ray light with a spectrum centered in 30kV.

    Rays have millions of volts and should be expected to produce X-rays of mega-electronvolts energy, this is gamma-ray energy levels.

    But Bremsstrahlung needs vacuum, so I probably don't know what I'm talking about.

    • Well, if you talk about electrons deflected by another particle or nucleus of an atom, it is no longer vacuum in the strictest sense, so i don't think the Bremsstrahlung effect needs vacuum, it can occur in any media. In fact the effect should be more prominent in thicker mediums, because the free electrons have bigger chance to get close enough to something to slow down. The Bremsstrahlung effect is caused by the electron losing it's kinetic energy because of deflection by another particle/atom nucleus etc
      • by Anonymous Coward

        You need to hit something to slow down or stop a high energy charged particle to create Bremsstrahlung, so in that sense you can't have a complete vacuum. However, in order to get that high energy particle in the first place, you typically need something close to a vacuum or a rather extreme environment along with an electric field, otherwise, the particle will hit too many things before accelerating to high speeds. It is like trying to play a game of red rover or British bulldog, where yes you need peopl

    • Bremsstrahlung does not need vacuum.
      How do you come to that idea? You have a fast moving particle and you "brems" it, slow it down, somewhere its energy needs to go. E.g. sending electrons in any material will slow them and produce Bremsstrahlung, that is how the phenomena was discovered.

    • It's not really 'centered' at 30kV. That is the maximum energy of the photons produced. Bremsstrahlung doesn't need a vacuum. You can get it whenever a charged particle accelerates.

    • Isn't thunder created by the vacuum of a collapsing ion trail from the lightning itself?

      So the lightning creates a super charged plasma, and that heat and ionization forms a vacuum. Coupled with anti-matter and xray burst you get your perfect Gamma-Ray engine.

      Now I did read that we could scan for life outside our solar system by looking for ionized light -- seems that the "left-handed chirality" of amino acids is do to the right-handedness of the more common organic compounds that a Yellow star creates. The

  • I wonder if this could mean people living in an area with lots of storms have a significantly higher risk of cancer. High altitudes do have risks:

    "A seven hour airplane trip exposes passengers to 0.02 mSv of radiation, which is a fraction of the exposure of a standard Chest x-ray (0.1 mSv). Domestic airline pilots are exposed to an additional 2.2 mSv per year, about the same dose as a brain CT." http://www.xrayrisk.com/faq.ph... [xrayrisk.com]

    "the high-altitudes expose climbers to an extra 1milliSievert (mSv) of radi

    • Re:health risks? (Score:5, Informative)

      by Mr D from 63 ( 3395377 ) on Thursday December 18, 2014 @06:41AM (#48624519)

      I wonder if this could mean people living in an area with lots of storms have a significantly higher risk of cancer.

      Higher risk, maybe, but imperceptibly small based on physical evidence. Even these "higher doses" are relatively small, well under the point where real world statistical evidence shows any increase in cancer rates. Fact is, other environmental causes dwarf radiation even at much higher doses when it comes to cancer risk. Now, if you get a hundred times these doses on a regular basis, you may expect to see some observable increases in certain cancers.

      Higher altitude exposure to UV is a real risk. Plenty of evidence for that.

  • Perhaps its phenomenons like these that inspire imagination of comic book heroes and si-fi stuff in movies...
  • I keep hearing that Gamma Rays are deadly, even a star 100 light years away can kill all life on earth. So, how are we producing these bursts without extinguishing life on Earth?

    • Size matters. Length matters.

      Or more appropriately, what matters here is the overall energy from the sum of all the photons involved in the dicsussion which are being called gamma rays here.

      If I shine a flashlight on you, you may barely, barely feel a bit of extra warmth from the photons hitting your body. If somehow I am able to shine a million such flashlights from the same distance simultaneously, you'll get a million more photons and you'll feel quite a bit warmer.

      What is disturbing about these DISTAN

  • Who else misread this as "terrorist gamma ray bursts?"

Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (10) Sorry, but that's too useful.

Working...