What has happened to the Sun? Solar wind speed drops to near 50-year low

  

September 2, 2011 – What has happened to the Sun? The solar winds have fallen to a low speed: 280.3 km/sec with a proton density event of 0.9 protons/cm3. The average solar wind speed is about 400 km per second. The diminishing solar activity, despite a plethora of sunspots painted across the surface of the Sun, led Space Weather to declare: “The solar disk is peppered with sunspot groups, at least eight of them. None of them, however, is producing strong flares. Solar activity remains generally low.” The last time the solar wind speed was this low was in 2008 when the solar wind velocity fell to 290.0 km with a proton density of 3.3 protons/cm3 but today’s reading is even lower than 2008. See 2008 solar wind reading:

The dismal output of solar activity in 2008 led NASA scientists to conclude: “A wind of charged particles that stream constantly from the sun is at its lowest level ever recorded in the 50 years since spacecraft have made the measurement possible. The Ulysses spacecraft observed the weak solar winds, the constant, high-speed stream of particles that races from the sun, during a quiet period in the sun’s activity. The solar weather cycle affects Earth and other planets in the solar system. “We know that the sun has been this cool before, this inactive before,” said Nancy Crooker, a physicist at Boston University in Boston, Mass., during a NASA teleconference on Tuesday. “But that was prior to the Space Age, so we didn’t have actual physical measurements until now.” The solar wind’s charged particles blow out from the sun at a blistering 1 million mph, sweeping away background radiation and colliding with incoming galactic cosmic rays from distant stars. It effectively encloses our solar system in a protective bubble called the heliosphere.” –Space.com -September 23, 2008

More Cosmic Rays hitting Earth: “The solar wind isn’t inflating the heliosphere as much as it used to,” says McComas. “That means less shielding against cosmic rays.” In addition to weakened solar wind, “Ulysses also finds that the sun’s underlying magnetic field has weakened by more than 30% since the mid-1990s,” says Posner. “This reduces natural shielding even more.” -NASA  -September 23, 2008

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