The Sun closed out a surprisingly active October with the release of a powerful X1-class solar flare on October 28, flinging a coronal mass ejection (CME) in the direction of Earth just in time for Halloween.
A CME is a powerful release of charged particles in the form of radiation. These charged particles are the same as what interacts with Earth's magnetic field to create the auroras at the north and south poles, but a CME is much more powerful than the typical solar winds.
While these CMEs can't hurt humans or other life forms on Earth, they can create geomagnetic storms that can wreak havoc on electronics and radio communications, as well as disrupt and even disable satellites in orbit.
NASA's Solar Dynamics Observatory captured the October 28th's solar flare erupting from its surface and classified it as an X-class solar flare, the most powerful class of flare possible on NASA's scale.
Fortunately, it was only an X1 solar flare, which makes it the least intense X-class flare possible. An X2 would have been twice the intensity of an X1, and an X3 would be twice the intensity of an X2, and so on.
Even though the CME was directed towards Earth, we didn't get hit with the full brunt of the CME. Even the glancing blow sent auroras to lower latitudes than normal, making them visible in parts of the world not accustomed to seeing one of nature's most spectacular light shows.