... The magnetic field of the Earth has been investigated by satellites for several decades now, and enough of it is known to model its average strength and shape during different levels of overall magnetic activity. Presently the most used empirical global magnetic field models are the Tsyganenko models (1987, 1989) , referred to as T87 and T89, respectively, although even these consist of several submodels. ... Earth's magnetic field from T89c model during Kp=2 for different seasons. ... Res. ...
... Future seminars . ... Long -term evolution of 27 days signal in solar activity and terrestrial magnetic indices - common features and differences ". ... The 27-day signal created by the solar rotation is reflected by the 27-day geomagnetic signal. We study the long-term evolution of the 27 days signal and compare its properties for solar and geomagnetic activity. ... We obtain that 'short' and 'long' period in the 27-days range are differently reflected in the solar and geomagnetic activity. ...
... Jupiter's icy moon Europa has a metallic core and layered internal structure similar to the Earth's , while the heavily cratered moon Callisto is a mixture of metallic rock and ice with no identifiable central core, according to new results from NASA's Galileo mission . In addition, recent plasma wave observations from Galileo show no evidence of a magnetic field or magnetosphere around Callisto, but do hint at the prospect of a tenuous atmosphere. ... Jupiter Galileo . ...