astrophysics Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the h ...

, a spacequake is a temblor in the

Earth's magnetic field Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic f ...

. Though occurring in space, the effects of a spacequake can reach the surface of the Earth in the form of electromagnetic reverberations. The total energy in a spacequake can rival that of a magnitude 5 or 6 earthquake. Spacequakes are measured using a

magnetometer A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, o ...

and displayed with a magnetogram. The precursors for a spacequake were discovered by

THEMIS In Greek mythology and Ancient Greek religion, religion, Themis (; grc, Θέμις, Themis, justice, law, custom) is one of the twelve Titans, Titan children of Gaia and Uranus (mythology), Uranus, and the second wife of Zeus. She is the godde ...

in 2007, and were first reported in April 2010 in a publication in the

Geophysical Research Letters ''Geophysical Research Letters'' is a biweekly peer-reviewed scientific journal of geoscience published by the American Geophysical Union that was established in 1974. The editor-in-chief is Harihar Rajaram. Aims and scope The journal aims for ra ...

''.

Cause

Spacequakes are caused when jets of plasma come into contact with the geomagnetic field some 30,000 km above Earth's equator. The impact sets off a rebounding process, in which the incoming plasma actually bounces up and down on the reverberating magnetic field until they dissipate in a process called repetitive flow rebuffing. When the plasma jets hit the inner magnetosphere, vortices with opposite sense of rotation appear and reappear on either side of the plasma jet.

Effect

When acting together, vortices and spacequakes could have a noticeable effect on Earth in the form of electromagnetic interference. The tails of vortices may funnel particles into Earth's atmosphere, sparking auroras and making waves of ionization that disturb radio communications and GPS. By tugging on surface magnetic fields, spacequakes generate currents in the very ground we walk on creating ground current surges.

References

Citations

Sources

This article incorporates text from the following public domain sources: * {{cite web, url=https://science.nasa.gov/science-news/science-at-nasa/2010/27jul_spacequakes/, title=Spacequakes Rumble near Earth - NASA Science, date=July 27, 2010, work=Science, publisher=

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

, access-date=29 January 2011

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