The Solar Wind.pdf
The Solar Wind.pdf The Solar Wind.pdf
• Observations of a CME in space– CMEs are often referred to asmagnetic clouds, bottles, or flux ropes.At 1 AU they take about a day to passthe Earth.– The axis of these may have anyorientation. The simplest rope lies inthe ecliptic plane orthogonal to theEarth-Sun line– Their identifying characteristic is aregion of nearly constant magneticfield strength with slow sinusoidalchanges in the two field angles. N isgenerally low.– If the cloud is traveling fast relative tothe solar wind a shock will form aheadof the cloud. The shock is evident fromthe increase in B, N, T (V T ), and V.These are called InterplanetaryShocks (IPS).• In the sheath between the shock andcloud the field and density arecompressed and turbulent.
• The magnetic field configuration of a magnetic cloudcan be inferred from the variation in the elevation.– At the beginning of the event the field is perpendicular to theecliptic plane.– After the cloud has passed the field has almost reverseddirection.– This is an indication of a magnetic field wrapped around thestructure – sometimes called a flux rope.– Note the increasing helicity of the field from the inside out.– The orientation of the magnetic cloud (i.e. whether is it norththen south or vice versa depends on the field at the source).
- Page 1 and 2: ESS 200CLectures 6 and 7The Solar W
- Page 3 and 4: • Solar wind speeds (heavy lines)
- Page 5 and 6: • It is useful to describe the so
- Page 8 and 9: • The transition from subsonic to
- Page 10 and 11: • For the solar wind to continue
- Page 12 and 13: • Waves and turbulence?- One poss
- Page 15: • In summary the outer layer of t
- Page 19: ω > Sunv ϕϕSun r r- At large dis
- Page 22: • A meridian view of the IMF- The
- Page 26 and 27: • Observations of high speed stre
- Page 28: • Time series of parameters assoc
- Page 31 and 32: • Plasma measurementsshow a drama
- Page 33: • A coronal mass ejection in spac
- Page 37 and 38: •The solar wind forms abubble, ca
- Page 39: • The Voyager passage through the
• <strong>The</strong> magnetic field configuration of a magnetic cloudcan be inferred from the variation in the elevation.– At the beginning of the event the field is perpendicular to theecliptic plane.– After the cloud has passed the field has almost reverseddirection.– This is an indication of a magnetic field wrapped around thestructure – sometimes called a flux rope.– Note the increasing helicity of the field from the inside out.– <strong>The</strong> orientation of the magnetic cloud (i.e. whether is it norththen south or vice versa depends on the field at the source).