The disturbance storm time index, also known as the Dst index or Kyoto Dst index, is a measure of the strength of the Earth's
ring current
A ring current is an electric current carried by charged particles trapped in a planet's magnetosphere. It is caused by the longitudinal drift of energetic (10–200 k eV) particles.
Earth
Earth's ring current is responsible for shielding th ...
.
The ring current around Earth produces a magnetic field that is directly opposite
Earth's magnetic field
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from structure of Earth, Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from ...
; that is, if the difference between solar electrons and protons gets higher, then Earth's magnetic field becomes weaker.
A negative Dst value means that Earth's magnetic field is weakened. This is particularly the case during solar storms.
Its units are typically measured in nT (nano-Tesla).
See also
*
K-index
References
External links
* Th
Dst index homepageprovided by Kyoto University
* Dst a
* Dst as part of SWENE
Latest Alerts (on
ESA's Space Weather Portal)
Planetary science
Radio frequency propagation
Electric and magnetic fields in matter
Solar System
Space weather
Electromagnetism
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