More details at docs.google.com.
For raw access to Maven Central, you can use Google's mirror: https://console.cloud.google.com/storage/browser/maven-central-eu/repos/central/data
First results as of 2018-11-13 are listed at https://github.com/jodastephen/jpms-module-names#modules-published-on-maven-central