closer and closer to the earliest life

More exciting origin-of-life research, focusing on adenine:

Many ex­pe­ri­ments have shown it: sim­ple mo­le­cules can com­bine chem­ic­ally—out­side of liv­ing things—to form the build­ing blocks of DNA, the key com­po­nent of life. But just how this com­bina­t­ion oc­curs is un­known. Sci­en­tists want to find out, since that might ex­plain how DNA orig­i­nat­ed.

Now, chem­ists have pro­posed what they call the first de­tailed, fea­si­ble ac­count of how one of DNA’s ma­jor build­ing blocks could have aris­en on an ear­ly, life­less Earth. The nec­es­sary in­gre­di­ents: five cy­a­nide molecules, they said.

The answers are tentative and raise further questions--but that's science.