This mesmerising image of the Northern Lights over Scotland was captured by Baltimore-born NASA astronaut Terry Virts, a member of Expedition 42 from the International Space Station earlier this week, as it drifted over Europe.
The aurora is caused by the interaction of the solar wind – a stream of charged particles escaping the Sun – and Earth’s magnetic field and atmosphere.
The Northern Lights or Aurora Borealis is a natural light display in the sky. Seen predominantly at high latitudes in both hemispheres, such as the Arctic and Antarctic regions of the Earth, typically 3° to 6° wide in latitude and between 10° and 20° from the geomagnetic poles, aurorae can occur at all local times, but are particularly striking phenomena over a dark night sky.
Auroras are caused by charged particles – mainly electrons and protons – streaming into the atmosphere from above causing ionisation and excitation of atmospheric constituents, and consequent optical emissions. Incident protons can also produce emissions as hydrogen atoms after gaining an electron from the atmosphere.
From the ground in Scotland, the Northern and Western isles, the Highlands and north east Scotland offer some of the best places to observe the observe the Northern Lights.
On 23rd November 2014, Mr Virts left the Baikonur Cosmodrome, in Kazakhstan in the Soyuz TMA-15M with two others to take up residence at the ISS. The ISS orbits between 370-460 kilometres (230-286 miles) above the Earth’s surface.
Colonel Virts is due to return to Earth in May 2015.