There are several ways that our species might try to send a message to another species separated from us by space and/or time. Synthetic biology might be used to write an epitaph to our species. or simply “Kilroy was here”. in the genome of a bacterium via the patterns of either (1) the codons to exploit Life's non-equilibrium character or (2) the bases themselves to exploit Life... https://parisnaturalfoodes.shop/product-category/cheesecloth/