Photo credit: Smithsonian Photo by Eric Long.
Now we place a black hole with the mass of Saturn over the middle of the Mall, and view the Castle through the resulting gravitational lens.
Click on the image for a higher resolution version.
Note that there are two images of each of the middle towers, one inside
the ring and one outside.
The inner image is turned inside-out.
These images form the logo for the CfA-Arizona Space Telescope Lens
Survey, CASTLeS .
Click here to see a press
release describing CASTLeS and these images.