Just a guess:
M27, M57, M76 and M97; the four planetary nebulae of the Messier catalog?
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"God bless thee, my son; I will give thee the greatest jewel I have ...
"The end of our foundation is the knowledge of causes, and secret motions of things; and the enlarging of the bounds of human empire, to the effecting of all things possible." Francis Bacon, The New Atlantis
Trying to make sense of computers, The Error Log.
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