Northern and Southern Lights
Aurorae (singular "aurora") are lights in the sky, usually observed somewhat close to either of the poles of the earth. The ones in the northern hemisphere are called Aurora Borealis or Northern Lights. The ones in the southern hemisphere are called Aurora Australis.
I have never seen any Aurora in person, unfortunately. One time, I was in New Hampshire, and one night there were supposed to be some, but it was very cold, and the place where I was had tall trees, so I didn't bother to go out and look, especially since I couldn't have taken pictures anyway. Taking pictures requires a special skill. I live too far south to see them otherwise.
Aurora displays are caused by an interaction between the Earth's ionosphere and solar winds.
There is no good topic for science that I can find, but since I want to see the aurorae and photograph them for myself, I put it on my bucket list.
(Photos Wikimedia Commons)
My Favorite Aurora Picture
This is one of my favorite pictures. It's widely used on the internet, but I will show it to you anyway.
This image has no copyright, and it was posted on Wikipedia. Wikipedia is a very good source for information (though you should use caution on political and certain scientific topics). It is like any other medium: biased. That's human nature.
Video of Auroras with Explanation
Videos of moving Aurora are hard to find. Most of them just have still pictures. This one includes an explanation of what causes Aurorae.
Jan Curtis has taken many pictures of Aurorae. I'm glad he's braving the cold so I don't have to! :)
He first started posting photos on the internet in 1995. I have known about his site for several years, and he and I exchanged a few emails. Here is one of my favorites of his photos.
This image was also featured on the Astronomy Picture of the Day, here:
The Astronomy Picture of the Day archives are a fabulous collection of images from space, and I highly recommend them. They include many photos from Hubble.
Jan Curtis' photographs have been featured more than once.
Here is Jan Curtis' web site: Aurora's Northern Lights
More Moving Aurorae
This video starts off rather slow, but there are some spectacular displays in the second half. These are Aurora Australis.
I don't know if this phenomenon is related to aurora or not, but it's still an interesting topic. A noctilucent cloud is one that looks white after dark. Usually they show up after the sunset is completed, but there is still twilight. The sun is still reflecting off the clouds in a faint sort of way, apparently. It is said they only occur in the higher latitudes. It is said the furthest south they have been observed in the United States is Colorado.
I have a tiny bit of news for them. I see them in Arizona! Not every night by any means, and of course we don't have clouds every night anyway. I'd like to figure out how to take a picture, but it's so dark, I haven't figured that out yet. But take my word for it. We get them.
Let us know if you have observed an Aurora, or just leave your comments.