Friday, September 26, 2014

Does Dark Matter Exist?


Dark Matter is one of those things you hear about, but you’re not quite sure what it is.  Supposedly, there is a bunch of this stuff that we can’t see, but somehow it makes up most of the universe--more stuff than the stars and the planets combined can account for.  For folks of a certain age, Dark Matter wasn’t taught in school because no one had proved its existence.

Thinking up Dark Matter is one thing, proving it exists is another.  Scientists have tried experiments in the Large Hadron Colider, where things spin around and smash into each other, but so far, no Dark Matter has flown out of these collisions.

Which is why recent discoveries by the Fermi space telescope are very exciting.  Wouldn’t you like to know what makes up most of the universe? I would.

The Fermi telescope detected Gamma Radiation coming from the center of our galaxy (the Milky Way).  Objects and events like supernova explosions, neutron stars and black holes produce Gamma Rays.  Radioactive decay--the breakdown of atomic objects--also makes Gamma Rays.  (Side note:  In the Marvel comic books, Gamma Radiation turned Bruce Banner into the Hulk.  Nuclear explosions do produce Gamma Rays, but not Hulks.  Most times.)

So when the Fermi telescope looked at our galaxy’s center it found Gamma Rays, which makes sense because of the neutron stars, pulsars, radioactive decay, etc.  But when you subtract all these known sources of the rays out, there was still a lot more Gamma Radiation.

What made this extra radiation? One explanation is that there is a dense concentration of Dark Matter at the center of our galaxy.  And when two Dark Matter particles collide, they produce debris in the form of Gamma Radiation.

At this point, we don’t have a Dark Matter Detector we can switch on and use to prove the existence of Dark Matter.  But courtesy of the Fermi telescope and some smart scientists, we have growing evidence that Dark Matter exists.  And that’s pretty darn interesting to think about.

1.  Here’s a Wired UK article titled “Telescope finds signal that could be destroying dark matter” by John Timmer.

2.  If you want to read more about Gamma Rays, try National Aeronautics and Space Administration, Science Mission Directorate. (2010). Gamma Rays.

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Author's Note:  If you enjoyed this article, please consider supporting Chimp With Pencil by buying one of my books.  Thank you.

1 comment:

  1. Dark matter. Pshaww Crazy Chimp. Can you imagine that most of the stuff in the universe is essentially so unthinkable that we almost dare not mention it in mixed company? As you said, we can’t teach our kids about it in school because we don’t know anything about it. Perhaps there is nothing to know about it since proof of existence is not quite there.
    For many the Golden Age of Space Exploration was the 1960’s and early 70’s. This is when we (humans) launched chimps without pencils into orbit then in short time had a man walking on the moon. Born in 1967, I really don’t remember much of the hype but it had to be an exciting time for science. Heroes were made in the likes of Buzz Aldrin, Neil Armstrong, John Glenn, and Alan Shepard. Who hasn’t said the immortal words of Jim Lovell, “Uhh, Houston we’ve had a problem.” All heroes. The Space Race and the challenge from JFK allowed Americans to spend a huge amount of money to sequester the brightest minds with a focus on space. Big things got accomplished – and fast.
    These days we don’t make heroes by sending folks into space, yet I put forth the argument that the Golden Age of Space Exploration is here and now. In the 70’s we explored the moon – an object that cavemen knew existed. Now we have several satellites orbiting other planets. There are videos of tornadoes on Mars, close up photos of a comet, evidence of planets outside of our solar system. We have a mission to land equipment on a comet – not crash into it, land on it! Comets travel fast. There’s a lot going on with NASA.
    The Chimp discussed the Drake equation a few months ago. I remember playing around with that equation years ago when the internet was a novelty for me. A coworker ridiculed and admonished me for thinking that other planets were possible, especially when I came up with a guess of habitable planets in the billions. Now NASA’s Kepler project has identified thousands of planets in other solar systems.
    So yeah, I think there’s dark matter. There’s a lot of stuff out there.
    - Grandpa Olaf

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