You spin me round like a record, baby

Real astronomers don't use high powered telescopes and quantum variable physics to determine the truth behind what planets are made of, both inside and out. Real astronomers spin eggs.

Also, our good friends in New Zealand somewhere smart and important have come up with a technical illustration diagraming the issue in their own article. Suffice to say, Mercury is akin to a Cadbury Creme Egg. The original big kind. Planetlicious.