This is in keeping with ancient myth where the two were thought of as being opposites, consequently the base we have made for Mars is sharp and angular while you will see that Venus’ base is more curvaceous and is blue as opposed to Mars’ red base.
The International Astronomical Union (IAU), through its Working Group for Planetary System Nomenclature (WGPSN), is the body that approves names proposed for planetary features. The IAU also makes rules and sets policy regarding planetary nomenclature. The United States is an adherent to the IAU, and we are therefore compelled to follow its dictates in naming planetary features. Among those rules that apply to Venus are the general rules that persons for whom features are to be named must be well known and deceased for at least three years. Names of persons prominent in any living religion or political or military figures of the 19th and 20th Centuries are disallowed. Furthermore, persons of a specific national significance are not acceptable. These rules are designed to avoid disruptive controversy that could obstruct the naming process. In addition, the IAU makes rules regarding the kind of names that will be given to different types of features. On Venus, craters and volcanic calderas (paterae) are named for women of history; craters less than 20 km in diameter are given female first names from various world cultures. Other types of features are named for mythological women. Names proposed for Venusian features must be selected from the proper category; otherwise, they are likely to be rejected. Consideration must also be given to keeping the nomenclature international in scope; that is, we must try to find and apply names from as many nationalities as possible. Name proposals should be submitted to the USGS in Flagstaff, as the Branch of Astrogeology has been charged by the IAU with the responsibility of maintaining a record of all planetary name requests, as well as managing, updating, and distributing data from the nomenclature master files. Once a specific name has been proposed for a feature, it must be reviewed by two different committees of the IAU. The proposal is then voted upon by the WGPSN at their annual meeting. Once a name has been approved by the WGPSN, it is considered to have “provisional” status. Provisional names may be used in publication, but their provisonal status must somehow be indicated in the publication. (Provisional names on USGS maps are indicated by an asterisk.)
The General Assembly of the IAU, which meets triannually, gives final approval to feature names. Because the naming process is a lengthy one, it asks mappers to make requests for feature names at the earliest possible time. As base maps become available, ozalid copies will be sent to Venus geologic mappers. Investigators will be asked to identify any unnamed features that they would like to have named. Mappers may propose names themselves, or a feature may be named by the nomenclature representative at USGS.