<p>Nomenclature on planetary bodies is meant to ease and standardize communication.  If an object is referred to often, or if it is important for someone's research, then the scientist(s) involved can submit a name request to the International Astronomical Union (IAU), or through some other body that submits names to the IAU (such as the United States Geologic Survey's Astrogeology branch in Flagstaff, AZ).  After checking for various criteria*, the name may or may not be approved.  If it is approved, then the feature is named.  If it is not approved, then the scientist(s) can resubmit that name or a different name.</p>

<p>I am not sure if it is a full list, but the <a href="https://planetarynames.wr.usgs.gov/Page/Categories" rel="nofollow noreferrer">USGS's Gazetteer of Planetary Nomenclature</a> lists a lot of the themes on different bodies.  Based on that, cavi and tholi would be named based on nearby albedo (brightness) features or craters.</p>

<p>*Criteria for naming are extensive.  Almost every type of feature (such as an impact crater) on many bodies has a theme, and that theme must be followed.  If the name does not meet that theme, then it will be rejected.  Other criteria are that the name cannot be offensive or induce a strong negative response (such as naming something "Satan" could induce a negative response in many people); the name cannot be used elsewhere in the solar system already (though some historic exceptions exist); the feature must be well defined (a vague region on a surface would not, therefore, qualify); the feature cannot be named after someone who is alive or has died less than three years ago; and there cannot be a preponderance of names that are biased towards or against gender, nationality, region of the world, etc.</p>

CC BY-SA 4.0
2020-03-21T07:05:34.543Z
For reference, I've been involved in recommending names for craters on Mars, and I've been involved with naming features on Pluto and Charon, both as part of my day job.
Stuart Robbins
CC BY-SA 4.0
2020-03-21T14:32:35.890Z
I see the idea of the theme. The cavus features are all named with a form of the word night, makes sense, Noctis Labyrinthus. I'm assuming naming a mensa (mesa) in the region would follow some thematic idea as well. Does that make sense to you?
Bob516
CC BY-SA 4.0
2020-03-21T17:11:19.267Z
I have edited my post to add the middle paragraph with the link to the naming themes.  For Mars, it's not that creative compared with, for example, Venus which has much more detailed requirements based on different features (possibly because they ran out of names when lumping things together).
Stuart Robbins
CC BY-SA 4.0
2020-03-21T07:02:24.327Z
2020-03-21T17:09:41.003Z
2020-03-21T17:09:41.003Z
Stuart Robbins
<p>I found this page <a href="https://astrogeology.usgs.gov/news/nomenclature/names-approved-for-six-cavi-and-a-tholus-on-mars" rel="nofollow noreferrer">Names Approved for Six Cavi and a Tholus on Mars</a> which lists seven features on Mars. I'm curious about the decisions to name only <a href="https://planetarynames.wr.usgs.gov/images/mc17_2014.pdf" rel="nofollow noreferrer">these features</a>: Dalu Cavus, Layl Cavus, Malam Cavus, Nat Cavus, Noc Cavus, Usiku Cavus, and Noctis Tholus in Noctis Labyrinthus. Why only some of the canyon, graben and/or valley locations are named?  Does it have to do with the depth of the features? <a href="https://i.sstatic.net/kuzBD.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/kuzBD.jpg" alt="enter image description here"></a></p>

<p>Doing a <a href="https://planetarynames.wr.usgs.gov/nomenclature/AdvancedSearch" rel="nofollow noreferrer">search</a> for the area of Noctis Labyrinthus, Northernmost Latitude: -3.0, Southernmost Latitude: -13.0, Westernmost Longitude: 259.0, Easternmost Longitude: 268.0, I found only this,
<a href="https://i.sstatic.net/TuoAS.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/TuoAS.png" alt="enter image description here"></a></p>

CC BY-SA 4.0
2020-03-19T22:39:52.300Z
Can't find enough names for *everything* in the Universe ?  Don't *need* names for most things ?
StephenG - Help Ukraine
CC BY-SA 4.0
2020-03-20T00:14:46.547Z
So why are those particular areas named?
Bob516
CC BY-SA 4.0
2020-03-20T02:09:33.380Z
Things you refer to and talk about tend to get names
planetmaker
<mars><iau><nomenclature>
Why are only some of the geologic features in Mars' Noctis Labyrinthus region named?
Bob516
# Why are only some of the geologic features in Mars' Noctis Labyrinthus region named?

(Asked by: username_0 on 2020-03-19)

I found this page [Names Approved for Six Cavi and a Tholus on Mars](https://astrogeology.usgs.gov/news/nomenclature/names-approved-for-six-cavi-and-a-tholus-on-mars) which lists seven features on Mars. I'm curious about the decisions to name only [these features](https://planetarynames.wr.usgs.gov/images/mc17_2014.pdf): Dalu Cavus, Layl Cavus, Malam Cavus, Nat Cavus, Noc Cavus, Usiku Cavus, and Noctis Tholus in Noctis Labyrinthus. Why only some of the canyon, graben and/or valley locations are named? Does it have to do with the depth of the features? [![enter image description here](https://i.sstatic.net/kuzBD.jpg)](https://i.sstatic.net/kuzBD.jpg)

Doing a [search](https://planetarynames.wr.usgs.gov/nomenclature/AdvancedSearch) for the area of Noctis Labyrinthus, Northernmost Latitude: -3.0, Southernmost Latitude: -13.0, Westernmost Longitude: 259.0, Easternmost Longitude: 268.0, I found only this,
[![enter image description here](https://i.sstatic.net/TuoAS.png)](https://i.sstatic.net/TuoAS.png)

**Tags:** mars, iau, nomenclature
> **Comments:**
> **username_1**: Can't find enough names for *everything* in the Universe ?  Don't *need* names for most things ?  
> **username_0**: So why are those particular areas named?  
> **username_2**: Things you refer to and talk about tend to get names  

---

## 1 answers

### Answer by username_3 on 2020-03-21. Score: 2 | Accepted answer

Nomenclature on planetary bodies is meant to ease and standardize communication. If an object is referred to often, or if it is important for someone's research, then the scientist(s) involved can submit a name request to the International Astronomical Union (IAU), or through some other body that submits names to the IAU (such as the United States Geologic Survey's Astrogeology branch in Flagstaff, AZ). After checking for various criteria\*, the name may or may not be approved. If it is approved, then the feature is named. If it is not approved, then the scientist(s) can resubmit that name or a different name.

I am not sure if it is a full list, but the [USGS's Gazetteer of Planetary Nomenclature](https://planetarynames.wr.usgs.gov/Page/Categories) lists a lot of the themes on different bodies. Based on that, cavi and tholi would be named based on nearby albedo (brightness) features or craters.

\*Criteria for naming are extensive. Almost every type of feature (such as an impact crater) on many bodies has a theme, and that theme must be followed. If the name does not meet that theme, then it will be rejected. Other criteria are that the name cannot be offensive or induce a strong negative response (such as naming something "Satan" could induce a negative response in many people); the name cannot be used elsewhere in the solar system already (though some historic exceptions exist); the feature must be well defined (a vague region on a surface would not, therefore, qualify); the feature cannot be named after someone who is alive or has died less than three years ago; and there cannot be a preponderance of names that are biased towards or against gender, nationality, region of the world, etc.

> **Comments:**
> **username_3**: For reference, I've been involved in recommending names for craters on Mars, and I've been involved with naming features on Pluto and Charon, both as part of my day job.  
> **username_0**: I see the idea of the theme. The cavus features are all named with a form of the word night, makes sense, Noctis Labyrinthus. I'm assuming naming a mensa (mesa) in the region would follow some thematic idea as well. Does that make sense to you?  
> **username_3**: I have edited my post to add the middle paragraph with the link to the naming themes.  For Mars, it's not that creative compared with, for example, Venus which has much more detailed requirements based on different features (possibly because they ran out of names when lumping things together).  

---

