Talk:Cart'hen system

I'll correct my edit comment. I read "radius", not "diameter" for some reason. Cart'hen II's a lot smaller than Pluto and Eris, is probably more comparable in size to Charon or Quaoar which are both Dwarf Planet candidates. The former is currently considered Pluto's largest moon.

The rereading also brings Cart'hen III into doubt. A diameter of 4378km puts that planet in the same ball park as Callisto (Jupiters' second largest moon) and Mercury, both have diameters in the 4800-4900km range. Density lacks a unit of measurement, but assuming it is g/cm³, that makes it more dense than any of the terrestrial planets in our solar system (all under 5.6). Surface gravity can be calculated using other stats using a formula found at List of Solar System objects by surface gravity. I've not tried checking that one myself. - Lt. Salak (Amateur Astronomer)^Talk 04:21, 4 March 2008 (CST)

Oh, and you'll be doing amazingly well to find a habitable planet around a White Dwarf. Earth like planets are only thiought possible around G type stars like our Sun, along with some F and K type stars. White Dwarfs are by definition D type. Unless I'm very much mistaken, any planets in their Goldilocks Zone would have been obliterated by the Red Giant preceeding it as its boundaries should be WITHIN the former suface of the Red Giant. Also, Cart'hen III is too small to hold on to an atmosphere, thus also too small for a runaway greenhouse effect (Venus style). Without that, to get those temps, it needs to be a LOT closer to its' star. For it to even exist, it would likely be a frozen wasteland, probably far closer in conditions to what Pluto is than to a Hot Desert. There would be no debris from the destroyed planets, they became part of the star, or the Planetary Nebula caused by the loss of its' outer shells when shrinking to a White Dwarf - Lt. Salak^Talk 05:30, 5 March 2008 (CST)

For comparison, for the White Dwarf IK Pegasi B, the average distance of the Habitable zone works out at around 0.35 AU. - Lt. Salak^Talk 05:57, 5 March 2008 (CST)

I guess I will have to go back and check my notes regarding that planet... I used an old roleplaying resourse book from about 20 years ago that I have... it details the creation of planets, star systems etc... it's possible I goofed some of the calculations... I was working on it while watching my kids... very possible i mixed up some of the numbers... then again the book is quite old... some sections are very likely out of date... and now useless... I will try and make the proper corrections to make Carth'hen III a more acceptable location... my Captain is hopeing it can become a reuseable gameing location... Canreb 5 March 2008

Had a feeling that could be the case, hence why I raised the issue :) - Lt. Salak^Talk 04:49, 6 March 2008 (CST)

class/mass

0.9 Solar masses would be G type. K type is roughly between 0.5 and 0.8 Solar masses. Our Sun is closer to F type than to K, being a G2. It could just about scrape through as a K type, but it's probably more likely to be a G7, G8 or similar. - Lt. Salak^Talk 00:33, 21 March 2008 (EDT)