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Greetings and NoLWoCS questions
#1
Long time lurker here, you can call me Mike. I have Asperger's syndrome and my affinity is astronomy. I have been aware of OA since 2003 after researching the old style reactionless drives. I was present in the old Yahoo mailing list and was probably one of the first to come over to this forum when it was created. But anyway...

Last week I was having a discussion with a friend about different types of planets and I sent him a link to the NoLWoCS EG to show it to him. After reading the article again, I noticed a couple of discrepancies. The big one making me break over a decade of lurking is the article for the LithicGelidian type, which cites Pluto as an example. At .002 Earth masses, Pluto is below the .05 Earth mass lower cutoff for the Terrestrial class. Also, at 2,376km Pluto is well above the 1,000km diameter upper cutoff for the Planetoid class. In short, Pluto is not massive enough to be in the Terrestrial class and has too large a diameter to be in the Planetoid class. This is happening because one class uses diameter as its defining size parameter while the one immediately above it uses mass, which are two different things that don't line up with each other very well. Although I understand why diameter was used to define the smallest of bodies in the NoLWoCS, a probable solution would be to change the size parameter for the Asteroid and Planetoid classes to mass like it is in the other classes.

The next one is probably a typo. On the Asteroid class EG, the third paragraph from the top defines a size parameter of 5 meters to 50km while everywhere else says 50 meters is the lower cutoff, even in the paragraphs above it. Most likely the 5 is supposed to be a 50.

The last one I can remember right now, Chthonian worlds appear to be both a subtype of the Superterrestrial class and a class of their own, independent from the six main classes of the NoLWoCS. Why are they a separate class? I think it would make more sense if they were a Terrestrial and Superterrestrial subtype, Chthonian and Superchthonian respectively. If Chthonian is a Terrestrial subtype, its not listed as such.

I want to close this by saying that the NoLWoCS is a work of art. John Dollan and all who contributed to it, if you're on here and haven't though of this already, please introduce it to the IAU so they can start using it. Responses to the above queries is appreciated.
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#2
Hi!
Greetings and welcome to OA!
John Dollan does occasionally pop into the OA forum, and I can pass your regards along to him even if he doesn't. I agree, the Planetary Classification List is a work of art, and any errors I have made in transcribing it into OA are mine, not his. I'll get these errors fixed in a few days.

One problem is that the mass classes are separate to the classes and types that are defined by temperature and composition, so that you can have superterrestrial LithicGelidian planets, terrestrial LithicGelidians and LithicGelidian planetoids, all with similar compositions but with very different mass and surface gravity. We could call them all by different names, or simply add a descriptive modifier in each case. I prefer the second option.

Of course there aren't any superterrestrial LithicGelidian worlds in our system, so we don't really know what they would be like - but they would almost certainly have significantly denser atmospheres than Pluto, and some interesting effects could occur on the surface of such a world.
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#3
(08-19-2018, 03:36 PM)stevebower Wrote: One problem is that the mass classes are separate to the classes and types that are defined by temperature and composition, so that you can have superterrestrial LithicGelidian planets, terrestrial LithicGelidians and LithicGelidian planetoids, all with similar compositions but with very different mass and surface gravity. We could call them all by different names, or simply add a descriptive modifier in each case. I prefer the second option.

Hey Steve, thanks for the reply. I had thought of this myself, I know that there are likely many types common to all three classes but were just never written up. So Pluto could be a SubLithicGelidian but it would still be out of bounds for the Planetoid class unless the size parameter were redefined. I also realized this morning that some of the real life examples of the Chronian (Tethys, Dione, Rhea, Iapetus), Titanian (Titan), Europan (Europa), and Hephaestian (Io) types are in the same position as Pluto, with diameters over 1,000km but masses below .05 Earths and thus, out of parameter for both classes.
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#4
We could make categories that fits between the current ones.
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#5
Hi - Welcome to OA!

The NoLWoCS isn't really my area of expertise, but hope to see you around the forum and have the chance to discuss various other things as we go along.

ToddSmile
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#6
(08-20-2018, 10:33 AM)Avengium Wrote: We could make categories that fits between the current ones.

Any class fitting between Terrestrial and Planetoid would be a fairly narrow margin, IMO. Reducing the lower mass threshold for the Terrestrial class would probably be the least amount of work as it would allow these types to be retained in that class and the archetypal bodies for which they are named could stay in their types. It may also help to change the size measurement for the Planetoid and Asteroid classes to mass just to make them more consistent with the rest of the NoLWoCS.
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#7
The Planetoid class mass-range should be increased to fill the gap between Terrestrial class and the current Planetoid class. Lots of objects will fall into this category- dwarf planets, moons, and oort-cloud objects. I'll probably get round to doing this on Wednesday when I have a little free time.
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#8
(08-20-2018, 05:19 PM)stevebowers Wrote: The Planetoid class mass-range should be increased to fill the gap between Terrestrial class and the current Planetoid class. Lots of objects will fall into this category- dwarf planets, moons, and oort-cloud objects. I'll probably get round to doing this on Wednesday when I have a little free time.

Sounds good Steve, I look forward to seeing the revisions.
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#9
I've edited the NOLWOCs article, and the LithicGelidian article, and the Planetoid article. Any other edits that should be made?
https://www.orionsarm.com/eg-article/468315d1708d3
https://www.orionsarm.com/eg-article/491c78b89879b
https://www.orionsarm.com/eg-article/47c1b64e522dd
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#10
(08-24-2018, 06:37 AM)stevebowers Wrote: I've edited the NOLWOCs article, and the LithicGelidian article, and the Planetoid article. Any other edits that should be made?

Looks good so far. I dont have much time right now but I'll go over this and review the rest of the NoLWoCS tonight to see if there are any more issues.
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