Stargazers in Utah, Colorado, New York and other US states were treated to a rare display in the early hours of this morning, when the first of two large coronal mass ejections from the Sun collided with the Earth's atmosphere, creating stunning Auroras.

A coronal mass ejection is an explosion inside the Sun that ejects a huge quantity of plasma into space. The plasma, composed of highly energetic particles, streams outwards, sometime striking Earth, where it can create stunning Aurorae, interfere with satellites in orbit, and in severe cases, even knock out electricity supplies.

The first mass of plasma was ejected from the Sun on 22 August, and was followed around 18 hours later by a second ejection. NASA announced that geomagnetic storms and Aurorae would be likely from 23 August onward.

The mass was ejected from the region of the Sun known as AR 798. The activity was associated with some relatively small solar flares. More flares in the region are still possible in the next 24 hours, according to NOAA, the space weather forecasters. ®

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