During the solar minimum, the magnetic field of the Sun, the Earth also has a magnetic field, looks a bit like an ordinary bar magnet with closed lines close to the Equator and open field lines near the poles. Scientist call those areas a dipole. The dipole field of the Sun is about as strong as a magnet on a refrigerator (around 50 gauss). The magnetic field of the Earth is about 100 times weaker.
Around solar maximum, when the sun reaches her maximum activity, many sunspots are visible on the visible solar disk. These sunspots are filled with magnetism and large magnetic field lines which run material along them. These field lines are often hundreds of times stronger than the surrounding dipole. This causes the magnetic field around the sun to be a very complex magnetic field with many disturbing field lines.
The magnetic field of our Sun doesn't stay around the Sun itself. The Solar Wind carries it through the Solar System untill it reaches the Heliopause. The Heliopause is the place where the solar wind comes to a stop and where it collides with the interstellar medium. That's why we call the magnetic field of the sun the Interplanetary Magnetic Field or IMF. Because the Sun turns around her axis (once in 27 days) the IMF has a spiral shape (called the Parker Spiral)
The IMF is a vectorquantity with a three axis component, two of which (Bx and By) are orientated
parallel to the ecliptic. The third component, the Bz value is perpendicular to the ecliptic and is
created by waves and other disturbances in the solar wind. When the IMF and the geomagnetic field
lines are reverse orientated, or not perpendicular to each other, it fails to reconnect with
each other that results into a transfer of energy, mass and momentum of the solar wind flow in the
magnetosphere. The strongest connection, with the most dramatic magnetospheric effects happens when
the Bz component is tilted heavily southward.
The Interplanetary Magnetic Field is weak near the Earth , variable in strength between 1 to 37nT with an average of 6nt.
The Bt value on the website is the strength of the Interplanetary Magnetic Field. How stronger it is how higher the chances for viewing the aurora. For Middle latitudes the values are good around 40nt, but the Bz component must be tilted south.
A strong southward Bz value is the most important value if we want to see some aurora. A strong southward orientated IMF gives us nice aurora displays so how lower it goes the better.
Um auch bei starkem Aurora Chancen zugänglich zu sein, haben wir eine schwere Server nötig dass mit alle Besuchern umgehen kann. Unterstützen Sie dieses Projekt das wir online können bleiben!
05:42 May 20 2013
|Mittelschwere M1.77 Sonneneruption|
22:36 May 19 2013
|Schwache CME Auswirkungen
Derzeit sehen wir die Auswirkungen der Ankunft eines koronalen Massenauswurf (CME) an der ACE-Satelliten. Der Sonnenwind Geschwindigkeit stieg mit 79.26 km/sec aus 455.5 km/sec.
06:24 May 18 2013
|G2 - Gemäßigten geomagnetischen Sturm (Kp 6.00) - Beobachter in hohen Breiten können einige schöne Zeiten der visuellen aurora. Die Chancen für den Mittleren Breiten noch relativ gering.|