APOD: MyCn 18: The Engraved Hourglass... (2019 Sep 29)

[Ann]

Below I try to compare a close-up from the core with the ring nebula. I think these type of planetary nebula are missing the hourglass ejection surfaces, as they have already dissolved. Therefore you can only see the central ring. The typical eye-like formation in the case of MyCn 18 results from the specific angle of view.

Jack from the AVAO team

Click to view full size image

Those two nebulas look similar when you crop and rotate them to match, but MyCn 18 likely at a much younger stage. NGC 3132 is probably older and in a less organized stage.

Thanks, Jack and Geck! What an interesting comparison!

Ann