Explorer is a fixed term in the sector: a block explorer lets anyone look up a transaction, inspect a block or follow an address. With bitcoin in front, the name describes that function exactly. The article the adds a sense of definiteness, as if naming the reference tool. Explorer also keeps its ordinary meaning, a person who travels and discovers, which opens the name to travel and adventure content. The .com ending suits a global audience.
The domain fits two families of projects. On the technical side: a clearly designed block explorer, a privacy-respecting transaction lookup, an analytics dashboard for researchers or a teaching tool that visualises how transactions move. On the editorial side: a travel guide to cities and businesses that accept bitcoin, a video series following someone who lives on bitcoin, or a podcast exploring the corners of the network.