Comments on: Scientists trace cosmic rays to massive black holes

By: goinggreen

goinggreen — Sun, 18 Nov 2007 17:24:04 +0000

This post is just for clarification Anthony. The particles observed by the Auger detector are of the Extremely High Energy (EHE) type and are very rare with the rate of around one of these particles hitting an area of one square kilometer about once a year. Most garden variety cosmic rays that are posited to affect the Earth’s climate are partially solar and partially galactic in origin and not not extragalactic.

The Sun is known to emit so-called low energy cosmic rays, and they are carried off in the solar wind. In addition, while the solar magnetic field varies in strength, other cosmic rays in our galaxy leak into our solar system. The amount that does depends on the varying strength of the solar field. This solar modulation is well measured and well-understood. The Auger-detected cosmic rays are of high enough energy that the sun’s and the galaxy’s magnetic field do not bend the path of these (charged) particles, and so they point back to whence they came.

The Auger result, if it stands with more statistics, is a remarkable one. The origin of these EHE cosmic rays has been an ongoing research project for over 40 years now and is clouded by the fact that they come from all directions. That the very highest (and rarest) ones come from a preferred direction is a great discovery.

By: Bill F

Bill F — Wed, 14 Nov 2007 23:08:39 +0000

I forget exactly who it was that published on it (Nir Shaviv perhaps?) but somebody had used BE10 isotope analysis to suggest that trips through the spiral arms of the galaxy greatly increased the cosmic ray flux to Earth and corresponded very well with large episodes of glaciation.

By: paminator

paminator — Sun, 11 Nov 2007 02:10:14 +0000

There was another recent article on large variations of high-energy cosmic rays (TeV) with a period of 62 Million years that may explain large swings in biodiversity. A (free) summary was published in the October, 2007 issue of Physics Today. The link is at-

http://ptonline.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PHTOAD000060000010000018000001&idtype=cvips

“Varying Cosmic-Ray Flux may explain cycles of biodiversity,” by Medvedev and Melott.

Some excerpts:

“The upshot of the nonlinear diffusion simulation is that the extragalactic cosmic-ray flux increases by almost a factor of five- not just 5%- as the solar system migrates from its southern to its northern extreme.”

“The authors also point out that ionization of the atmosphere by cosmic rays can affect climate, electrical storm activity and atmospheric chemistry: There’s good evidence that ionization facilitates cloud formation, which in turn increases the planet’s albedo.”

By: Russ

Russ — Sat, 10 Nov 2007 19:01:30 +0000

Anthony,
Awesome graphic. I will be posting a link from Dalton Minimum Returns. I wonder if some of our ice ages are from some excess cosmic rays when we get burst of cosmic rays when a black hole swallows a solar system, or another galaxy and we get sprayed with the cosmic splash.