CME IMPACT: A coronal mass ejection hit Earth’s magnetic field on Sept. 30th at 10:25 UT. The impact was weak, lifting the solar wind speed around Earth barely above 300 km/s. Nevertheless, auroras are possible around the Arctic Circle as Earth’s magnetic field reverberates from the impact. Aurora alerts: text, voice.

The CME was propelled into space on Sept. 28th by an eruption of sunspot AR1577. The Solar and Heliospheric Observatory caught the cloud expanding toward Earth at 2.2 million mph:

Although the initial impact was weak, a geomagnetic storm could develop in the wake of the CME.

from:    spaceweather.com