Notwithstanding What Bill Nye Says, the Sun Is Not an Unremarkable Star - Daniel Bakken - December 1, 2014 Excerpt: Notwithstanding what Bill Nye says, the Sun is not an unremarkable star. It is larger than over 95% of stars in the galaxy.,,, Stars with masses of 0.1-0.5 solar mass make up 75 percent of the stars in our Milky Way galaxy.6 These represent the red dwarfs, the M class. But these stars have low effective temperatures, and thus emit their peak radiation at longer wavelengths (red and near-infrared),, But a serious problem with red dwarf stars in the K and M classes is their energetic flares and coronal mass ejection events. Potentially habitable planets need to orbit these stars closer, to be in these stars habitable zones. Yet the exposure to their stellar winds and more frequent and energetic flares becomes a serious issue for habitability. Because of these stars smaller mass, ejections get released with more violence.9 Any planets atmosphere would be subject to this ionizing radiation, and likely expose any surface life to much more damaging radiation,,, Another requirement for habitable planets is a strong magnetic field to prevent their atmosphere from being lost to the solar winds. Planets orbiting a red dwarf star are also more affected by the stars tidal effects, slowing the planets rotation rate. It is thought that strong magnetic fields are generated in part by the planets rotation.15 If the planet is tidally braked, then any potential for a significant magnetic field is likely to be seriously degraded. This will lead to loss of water and other gases from the planets atmosphere to the stellar winds.16 We see this in our solar system, where both Mercury and Venus, which orbit closer to the Sun than Earth, have very slow rotation rates, and very modest magnetic fields. Mercury has very little water, and surprisingly, neither does Venus. Even though Venus has a very dense atmosphere, it is very dry. This is due to UV radiation splitting the water molecules when they get high in the atmosphere, and then the hydrogen is lost to space, primarily, again, by solar wind.17,,, etc.. evolutionnews.org/2014/12/notwithstanding091571.html
Posted on: Tue, 02 Dec 2014 02:33:21 +0000
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