The spacecraft was similar to one that would carry humans, and scientists were interested in measuring galactic cosmic rays and solar energetic particles on the trip.

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When the sun is at its most active, which is when it is spotty, the solar wind is stronger and fewer cosmic rays penetrate.

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Conversely, when solar activity is less intense, more cosmic rays get through.

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As noted in the paper, the IPCC models also fail to incorporate climate modulating effects of solar changes such as cloud-forming influences of cosmic rays throughout periods of reduced sunspot activity.

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The Sun's magnetic field and solar wind - mainly in the form of electrons and protons coming out of the Sun - protects the entire Solar System by acting as a sort of shield from cosmic rays (very energetic particles and radiation from outer space).

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DMI, Henrik Svensmark, reasoned that if the solar cycle were linked to the earth's temperature, cosmic rays could be part of the chain.

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X-rays and gamma rays that Eros gives off in response to bombardment by solar and cosmic radiation.

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Other that it is all natural caused by changes in solar activity, the angle of the axis of the earth, something, anything, and now cosmic rays and the formation of Aitken nuclei.

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