How to search SIMBAD using identifiers?
If you look on the main SIMBAD page, you will see the following in the box titled &quot;Content&quot;:

The SIMBAD astronomical database provides basic data, cross-identifications, bibliography and measurements for astronomical objects outside the solar system.

(emphasis mine)
The Moon and the Sun are inside the Solar System, thus they are out-of-scope for SIMBAD.