The Northern Lights made an unusually brilliant appearance as far south as Oslo late last week, and readers sent in their photos of the phenomenon.This one was snapped from a backyard in Oslo's Grønland district downtown.

Here's a shot of the Northern Lights
(Aurora Borealis, Nordlys) with the lights of Oslo in the background.

The green shimmering of the Northern Lights was especially bright over Simensbråten in Oslo.

Here's how the Northern Lights looked from Holmlia, in southeast Oslo.

Ulv Sandberg sent in this photo of how the skies looked over Sandefjord, which is a two-hour drive south of Oslo along the coast.

This was one of the sightings over Nadderud in Bærum, just west of Oslo.

The Northern Lights are much more common over Northern Norway, as in this photo from Helge Kalseth in Tromsø. Last week's sightings were attributed to an unusually strong solar storm.

Finally, the Northern Lights as seen over the research station EISCAT near Tromsø.