http://hubblesite.org/This is the official Hubble telescope site. It has all the amazing pictures taken by the Hubble space telescope. You can view them in an image tour that has tons of info about what your looking at. The image tours are amazing and very informative. You can also look at all the images in the gallery. They have wallpaper that you can set to your background.
Besides the pictures, you can learn about the Hubble and everything astronomy. There is so much info and interactive stuff on the site. It's a great resource for teaching about astronomy.
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