Magnetic storms have been photographed hitching a ride on Comet Catalina’s tail.
Comet Catalina, also known as C/2013 US10 is passing us right now, set on a deep space course out of our galaxy.
The comet came to perihelion (closest approach to the Sun) on 15 November 2015 at a distance of 0.82 AU from the Sun.
At perihelion, it had a velocity of 46.4 km/s (104,000 mph) with respect to the Sun which is slightly greater than the Sun’s escape velocity at that distance. It crosses the celestial equator on 17 December 2015 becoming a northern hemisphere object. On 17 January 2016 the comet will pass 0.72 AU (108,000,000 km; 67,000,000 mi) from Earth and should be around magnitude 5.5 while located in the constellation of Ursa Major.
It is not uncommon for a comet to have magnetic storms catching a ride, the magnetic storms are similar to Earth’s geomagnetic storms.
A geomagnetic storm is a temporary disturbance of the Earth’s magnetosphere caused by a solar wind shock wave and/or cloud of magnetic field that interacts with the Earth’s magnetic field. The increase in the solar wind pressure initially compresses the magnetosphere.