Stargazing is a neurological disorder that causes really unsteady, uncontrolled movement in corn snakes. It gets worse when the snakes are excited. They struggle to right themselves when put on their back, and they bob and weave like crazy. It is not necessarily a death sentence, but it's definitely not something that people want in their collection.

Here is a video of some stargazers from specialcorns.com
https://www.youtube.com/watch?v=2bZgTWoLPuc

The reason people DO keep them is to test other snakes for the gene. Since there is no DNA test for the gene, the only way to know if a snake carries it is to breed it to a snake that definitely has the gene. That's how Flower came to be...the breeder was testing her mother for stargazing by breedig her to a male that definitely carries it. Since none of the 17 babies were stargazers, the mother is almost certainly clear of the gene. Most of the babies were low-end morphs that could be marked down as "pet only - no breeding" without concern....but there was one Peppermint and one Shatter...which is even more unusual than the peppermint! My friend is keeping the Shatter for herself, and I got miss Flower!