NGC 3918 is one of the more complex planetary nebulas. If we could see a ten-thousand year movie of it we could understand it a bit better. Too bad that's impossible. If you find a young planetary nebula you could start now and have many subsequent generations of humans continue to perform the task, supposing that they care enough about it and have the necessary resources. I have a hard enough time looking at just twenty years of archival data. I can't even begin to imagine ten-thousand years.

I had to significantly dim the bright center to reveal all the knots around the core.

Red: hst_06119_18_wfpc2_f814w_pc_sci + hst_11122_08_wfpc2_f658n_pc_sci Green: hst_06119_18_wfpc2_f555w_pc_sci + hst_11122_08_wfpc2_f656n_pc_sci Blue: hst_11122_08_wfpc2_f502n_pc_sci