[CWBP2] Astrophysics

[EpicSpire]

The mass-luminosity relationship on your star is badly cockeyed. A star with a mass of 4.29 Sols should have a luminosity of much more than 4.29. As a rule of thumb, I use L = M^3.5.

For planets with the same insolation, larger stars should have longer years. I'm not even sure if a mass of 4.29 Sols would have a sufficiently long life to evolve complex.. life.

Thanks for pointing that out, Universe Sandbox does have the Mass to Luminosity option and for some reason i have it unchecked. but as far as i understand, Larger stars burn more quickly and will die faster than smaller ones,.. which is why White Dwarfs have to be older than the current age of the universe in order to actually burn white. correct me if i'm wrong or misread your statement.

Thanks, I already know about that software but not that a second version is coming.

You planet is not in the habitable zone, it will be cooked like a roasted chicken in no time.

The planet is in the habitable zone. it is far enough from the planet to have a temperature of 63F. and is within the Habitable zone that the program calculates when that option is selected for viewing. what makes you think it isn't?

[Azélor]

Your orbital period is 300 days, it's shorter than our own and usually mean that the planet is closer to the star.

I could verify the distance but I think it's too close the be in the habitable zone considering the brightness of the star.


Is it possible that you star is not a main sequence star?
because I can't find a class that match all your informations: http://en.wikipedia.org/wiki/Stellar_classification

mass: B
diameter: M
Density: your density is 115 times the Sun density. It's possible to have main sequence stars denser than the Sun but not that much.
temp: B
lum: B
color: A or B

Most of your informations seems to point out to a B star class. If you increase the diameter, normally, the density will get smaller and you will be able to match the average B star size. But with universe sandbox, it's always hard to get the numbers right because of how the sliders work.


And at that distance your people are gonna die fast. Try with Sirius as an example, it's over 300 degrees. The planet is about 1/3 of the way from the habitable zone.

[EpicSpire]

Your orbital period is 300 days, it's shorter than our own and usually mean that the planet is closer to the star.

I could verify the distance but I think it's too close the be in the habitable zone considering the brightness of the star.


Is it possible that you star is not a main sequence star?
...
Most of your informations seems to point out to a B star class. If you increase the diameter, normally, the density will get smaller and you will be able to match the average B star size. But with universe sandbox, it's always hard to get the numbers right because of how the sliders work.

Thanks for the information, i'll run it through Universe Sandbox again, i did double check and the mass to luminosity checkbox was checked so there isn't a reason for the luminosity to be off by so much. I am not opposed to the star not being a main Sequence star, hell the system isn't even in our galaxy. I did originally plan the planet to orbit a white dwarf and it has always had a 300 day year, so i placed the planet at a 300 day orbit and adjusted the temp of the star until the planet reached 17.5 C. when i checked habitable zone, the planet was within the green rings (between the 2 bands not inside the inner band). although i just now re-looked up the mass of a white dwarf and saw that my mass is way off.. which had to be a slip of the slider, so again thanks for your information, still weird that the planet's orbit and temp isn't thrown off by the mass shift.

I'm trying to force myself to look at believably the way a random reader of my books would... it's them *I* would have to convince with my own worlds.

I'm simply trying the same viewpoint here

Having questionable stuff is fine, as long as you've got the answers for it

this is exactly how i feel when trying to come up with the system for my world. I'm glad i found this thread, and i will be willing to help out with anything i can, while using the knowledge/information i gain here for my own project. turning my game/book/story setting into something that provokes the Suspension of Disbelief is hard when you are as OCD about creative logic as I am.

[Azélor]

Let's make a summary of this thread, our planets and stars still need names

Star system summary:

Main star: G star class, a little smaller than the Sun to compensate the influence of the second star.

Planet 1: Tide locked, close to star. Iron planet
Planet 2: Old drifter, much orbital debris. Chthonian planet
Planet 3: hot gas planet, Blue hot Jupiter
Planet 4: Earth-like but 30% bigger, orbit close to CWBP 2, two moons. Silicate planet
Planet 5: CWBP 2 planet: 2 satellites, the second is in another dimension. Silicate planet
Planet 6: Ice rock smaller than Venus. Silicate planet
Planet 7: Beige gas giant. Jupiter-like (ammonia)
Planet 8: large terrestrial planet, large oceans covered by ice
Planet 9: Ice giant, appear white-blue, larger than Jupiter

Second star



1-A planet orbiting close to the star. It is tide locked. The planet is so close that it is difficult to see it from our world. Under the right conditions, at dawn/dusk, a small and reddish sphere appear in the sky close to the star. It's possible to see her only for a very short moment in the best scenario. Being close to the star mean it's a lot hotter on the tidal locked face, but the other side is freezing cold. And finally, the tidal energy generates heat in the planets resulting in a lot of geothermal activities.

Diameter: 6578 km
Mass: 0,24 Earths
Density: 9,42 g/cm
Hill sphere: none
Satellites: impossible
Temperature: 443 °C
Distance form main star: 25 m km
Orbital period: 25 days
Color: reddish

2- The second planet is an old one. We don’t know where it came from but it could be older that our star. She probably drifted for some time in space before gaining the actual orbit. Her obit is pretty eccentric. Temperatures on the planet are extreme since the rotation takes more than 3 terrestrial years to complete and has a strong inclination. The center of the planet is almost completely cooled off. The planet has near to zero magnetic fields given its slow rotation and the small size of its melted core. Is has a very thin atmosphere with different gases and water. During its life, many objects came in collision with the planet. That's why there are so many craters and water in the atmosphere. There is also a lot of debris floating around the planet. Some of them rotate at more than 1 million km but most are orbiting closer in a planetary ring. The color of the planet is a pale gray and she is smaller than Venus. This planet is visible with naked eyes. It is a chthonian planet that lost the outer layers of gas. Only the dense metal rich core of the planet is still there.

Diameter: 11 399 km
Mass: 0,78 Earths
Density: 6,01 g/cm
Hill sphere: 0,4 m km
Satellites: a lot of debris small and larger
Temperature: 256 °C
Distance form main star: 43 m km
Orbital period: 56,3 days
Color: grayish-brown

3: The third planet is a gas giant known as a Hot Jupiter. The planet mass is about the same as Earth but it’s mostly made of hot gas. Hot gases take a larger volume. Interestingly, the planet formed away from the star and moved probably during the collapse of the other star. The planet lost some of the outer layers of gas over time but it’s almost stable now.

Diameter: 32 000 km
Mass: 2,75 Earths
Density:0,94 g/cm
Hill sphere: 1 m km
Satellites: a few
Temperature: 106 °C
Distance form main star: 87 m km
Orbital period: 162 days
Color: Deep blue

4- The fourth planet is orbiting pretty close to our world and is in the habitable zone too. The gravity is stronger which allows for a thicker and denser atmosphere. The planet is more inclined (30 degrees) so climates are more extreme between the seasons.

Diameter: 18 708
Mass: 3,16 Earths
Density:5,50 g/cm
Hill sphere: 1,5 m km
Satellites: 2 confirmed
Temperature: 27,6 °C (lifeforms)
Distance form main star: 137 m km
Orbital period: 324 days
1 day= 36 h
Color: like Earth
Gravity: 1,4 times the gravity of Earth

Satellite 1:
Diameter: 4051 km
Mass: 2,57 Moons
Density 5,43 g/cm
Distance: 81 500 (is tide locked)
Orbital period: 36 h

Satellite 2:
Diameter: 1501 km
Mass: 0,054 Moon
Density 2,26 g/cm
Distance: 330 000 km
Orbital period: 12,3 days

5- CWBP 2 world ...(advanced lifeforms)

6- The sixth planet is a cold planet. It's almost all covered with a thick layer of ice which reflect a lot of light into space. It is said that it can also reflect the light of the old star.

Diameter: 11 265 km
Mass: 0,68 Earths
Density: 5,43 g/cm
Hill sphere: 1,5 m km
Satellites: possible
Temperature: -36 °C (is at the limit of the habitable zone but too cold)
Distance form main star: 1,38 AU
Orbital period: 1, 62 years
Color: pale gray
Gravity: 0,88 time the gravity of Earth

7- The seventh planet is a beige gas giant (Sudarsky Class I) probably made of ammonia and methane.

Diameter: 104 210 km
Mass: 74,5 Earths
Density:0,75 g/cm
Hill sphere: 12 m km
Satellites: could have a lot
Temperature: -80 °C
Distance form main star: 2,23 AU
Orbital period: 3,33 years
Color: beige

8- The 8th planet is a large terrestrial planet: This planet is much larger than the 4th planet, making it visible at that distance. A solid and dense core is covered by an ocean several kilometers deep and recovered with a thick layer of ice.

Diameter: 24 900 km
Mass: 3,25 Earths
Density:2,38 g/cm
Hill sphere: 12 m km
Satellites: could have some
Temperature: -171 °C
Distance form main star: 5,85
Orbital period: 14,1 years
Color: white

9- The 9th and last planet is a gas giant. In fact, it’s a super Jupiter planet almost twice the size of Jupiter but with much lighter. It can also be called a puffy planet because of its low density. Mostly made of methane.

Diameter: 234 130 km
Mass: 0,39 Jupiter
Density: 0,11 g/cm
Hill sphere: 75 m km
Satellites: a lot
Temperature: -185 °C
Distance form main star: 10,8 AU
Orbital period: 35,3 YEARS
Color: pale blue

The Second Star
Is making the planet 8-9 Kelvin hotter. The luminosity of the star has a variation of 7% depending the season.
The second star has her own smaller system but it’s not visible from our planet.

-6 is the apparent magnitude of the star as seen from the planet when the distance is 75 AU.
It’s nearly 3 times brighter than Venus and 600 times fainter than the full moon.
This white dwarf is probably the result of a collapsed star. It’s been such a long time that the nebula surrounding it has disappeared. Invisible but some particles are still there. The planet have been irradiated for almost 10 000 years with particles and debris. It was so hot that the surface of the planet crust melted. The particles are now part of the plant’s geology. They are scattered and can be found at different layers in the crust. Mostly in deeper locations it can get closer to the surface at some point. Star metal, star dust anyone? Maybe we can find a cooler name than that: celestial metal?

Diameter: 19 270 km
Mass: 0,64 Sun
Density: 339 800 g/cm
Hill sphere: 10 AU ?
Satellites:
Temperature: 9498 °C
habitable zone between 5 and 7 m km
Distance form main star: 75 AU
Orbital period: 507 years
Color: blue-white

The 8 planets and the second star are known as the 9 wandering stars…

[Azélor]

I made a graphic representation of the system. It's on scale. Well, it uses 3 different scales. 1 for the planets, 1 for the distances and the other is for the star. The star, compared to the planets is only 8% of her real size. And of course the scale for the distances and planets are really different, if they were on the same scale, the map would be mostly black.

I had to cut it but the original include the other star too at 75 AU. But at that distance it become big as a pixel.
As you can see I used a perspective. For artistic and practical reasons. I wanted to avoid having some planets covering too much of the space. There is an axis than goes more or less for top left to bottom right. The farther objects are from the axis, the smaller they appear but object that are closer also appear larger. I left 2 version of planet 6 to show what I mean. It's more or less accurate.


The two last planets look lost in space. I could put them on the same side or change their orbit... Or maybe I could make the map only including planet 1-7.
They don't have names yet and suggestions are welcome. I always take a lot of time to find good names.

Attachment 67197

[Falconius]

Planet 7, Goomswaba.

[Azélor]

it sounds funny. Does it have a particular meaning ?

not bad I'v seen worst: https://www.google.ca/search?q=Gooms...+Swaba&spell=1

It seems to be related to medicine, possibly for animals

[Falconius]

Naw, I was just joking, it sounded funny to me for a planet name. In any case I would expect they are named differently by different cultures. It was really only once Planets stopped being recognized as divine that their names started being more uniformly accepted. For me I imagine a portion of our world to be in the beginning of a period of enlightenment. As for our dominant/most powerful culture I'll just assume we are using English as a stand in. Meaning the names would probably be much more anglo sounding than good ole' Goomswaba.

[Azélor]

No, now that you said the name I can't get it off my head

Gonsvabia
Gonswaba
Gonsawba
Gonsaoba (portugese ?)
Conswaba
Goonswabia (certainly not)

Bagooswan
Wambagoo
Goombawa

And the planets had a common known name (at least in the Western world) Maybe other cultures used the sames names (Arabs, Indians?) because they had some cultural ties but certainly not the Chinese or the Aztecs.
But we can't manage 4 or 5 different sets of names. The same is true for some geographic names. Continents could have a very similar name from culture to culture (not sure) but some oceans will receive different names. As of today, some of the World seas have more than one name.

It does create the problem as : how to name things? For example: Should all continents have their name in a relatively similar language ? by avoiding mixing names like Boston and Ouagadougou. to make it look like it was named by just one culture.
But even when you try to stay in the same language, time will influence the names. When I look at some French places, some names look foreign. Not surprising considering they had the influence of different cultures. If you understand French, you should look at some Haitian villages, these are the weirdest names I've seen.

So, should we just try to use names that sounds cool or use some sort of informal conlang?

[Falconius]

I think in a case such as this style out rules substance. So cool sounding names is the way to go. In any case languages really only apply themselves to very small areas generally, most of the time countries share far more than one. Colonizing has always been a very human motivation and done since the beginning of recorded history so I'm sure we will see some interesting language spread. Especially if folks finish a map and move the same culture somewhere else and begin a new map (especially with the tunnelling node idea). I'd say no limits on having disparate sounding names on the same land area, it's better to explain it with story than it is to try and force an imposed idea of what we find natural.