View Full Version : CWBP 2 : Astrophysics

02-02-2014, 03:04 PM
We talked about it in the Genre and era thread but noting conclusive came out of the thread concerning this topic
This is the thread to discuss (quote form Wikipedia):

Astrophysics (from Greek astron, ἄστρον "star", and physis, φύσις "nature") is the branch of astronomy that deals with the physics of the universe, including the physical properties of celestial objects, as well as their interactions and behavior. Among the objects studied are galaxies, stars, planets, extrasolar planets, the interstellar medium and the cosmic microwave background.

So… for those that don’t want an earth like planet, this is the place to talk about it.

Star: how many, what size?
Planet: distance from the sun, tilting angle, size, magnetic field, number and size of moons, speed of rotation, atmospheric composition…
Other planets: for those that are interested in developing the rest of the star system
Constellations and everything out of the system: it could be an area for development

02-03-2014, 09:26 AM
You started this without your own suggestions. Personally I like your double star with one being small or distant, you should elaborate on it a little.

Another idea I'm fond with from the other thread is a moon with a twin that is out of phase dimensionally speaking and appears or disappears, or fade in and fades out dependent upon both the strength of the "Main" moon and the "spiritual" condition of the world (ie tied into the "guilt that haunts" mechanic). For instance I think it would be neat for those who have the sight, to be able to foretell omens by the way the second moon is behaving or its interaction with the Main moon. Also I'm still a fan of having some sort of presence on the moon, supernatural or otherworldly in someway (positive in nature, as opposed to demons say).

And for some reason I'm also stuck on the idea of a twin world, but that is more just a passing thought.

Other than that I for sticking with earth like for most variables since it is a lot easier to deal with conceptually.

02-03-2014, 12:52 PM
I made this to explain the binary star idea


your idea is not bad, is the second moon magical ?

02-03-2014, 01:03 PM
Yeah pretty much magical I guess. I was thinking more along the lines of it being uniquely extra dimensional in its own little space, which sort of intersect with "ours." Or as if the object was slightly out of phase with our universe (in the sci-fi sense).

Edit: lol I love that our planet is designated cwbp2 in this example! Yeah that looks really cool to me. The only subject I'm not sure about is how it would affect the day/night cycle?

02-03-2014, 04:56 PM
Hum, at 75 AU it's nearly 4 times the distance Sun-Uranus and the star is 40% less luminous or so. My guess is that the impact would be really small. My simulator showed less than 1 Celsius degree in temperature difference.

Do you play Dnd ? There is something called the plane of shadow and the etheral plane : SRD:Plane of Shadow - D&D Wiki (http://www.dandwiki.com/wiki/SRD:Plane_of_Shadow)
the moon is in fact located in another plane of existence. Usually, it's not possible to see it but under certain circumstances it is.

02-10-2014, 05:50 PM
Hum, at 75 AU it's nearly 4 times the distance Sun-Uranus and the star is 40% less luminous or so. My guess is that the impact would be really small. My simulator showed less than 1 Celsius degree in temperature difference.

Do you play Dnd ? There is something called the plane of shadow and the etheral plane : SRD:Plane of Shadow - D&D Wiki (http://www.dandwiki.com/wiki/SRD:Plane_of_Shadow)
the moon is in fact located in another plane of existence. Usually, it's not possible to see it but under certain circumstances it is.

This is the post that confuseded me :P

02-12-2014, 11:36 AM
This is the post that confuseded me :PWhat is confusing to you there? The star part or the moon part.

In any case I think that unless there are any objections, we should move forward with Azelor's star idea and my extra dimensional magic moon. Meaning we should work under the assumption they are part of the world.

02-12-2014, 11:49 AM
:P I meant that it confused me (re: another thread) about the star being the multi-dimensional body, rather than the moon. My brain sort of just squished the ideas together.

I agree, I'm all for both of them :) I was just mixed up o.o

02-12-2014, 08:53 PM
What is confusing to you there? The star part or the moon part.

In any case I think that unless there are any objections, we should move forward with Azelor's star idea and my extra dimensional magic moon. Meaning we should work under the assumption they are part of the world.

I'm good with that unless someone is against these two ideas.

So the secondary star should be smaller, and more importantly less massive than the main star. At first I was going to put a orange dwarf (K star), but a white dwarf is also interesting. White dwarf are old stars that have ended the main sequence, which mean they have run out of hydrogen to fuse into helium... the star was a mid sized star ( around 0,5 and 10 solar masses). It runs out of fuel at around 1-5 billions years.. At the end of her life, the star had become really huge (not necessarily massive) and really bright. But eventually, the star begin to contract, and as it contract it emits gases and particles like some sort of nebula (which looks really cool). The star is really hot at that moment, as high as 150 000K on the surface but the inside it much hotter. The temperature cools off very fast and it slow down afterwards. The temperature of a white dwarf could be almost stable at around 5000-6000K (or maybe higher) for a very long time and the lifespan of a white dwarf is estimated at something like 10 0000 000 000 000 000 000 000 000 000 000 years or more... anyway, a long time.

The main star is more recent. It would have formed either before or after the collapse of the old star. No matter how we put it, life would have not been possible on the planet prior to the collapse because the star was too bright. It mean that the collapse happened somewhere between 3-6 billion years ago.

The old star could be associated with : death, evil, shadow, magic or stuff like that since it's an old, dense, with a strong magnetic field, inhospitable place. She could have mystical/magical proprieties. The nebula thing is interesting, especially if the star have special proprieties because these particles would have spread to all surrounding planets. But after 3 billions years, the visual part of it would be long gone.

about the moon idea now: it's a secondary and smaller moon that does not appear all the time because she is in another dimension. A dimension more or less similar to ours that is superimposed. She usually on the other side but from time to time, she become visible. It's not clear if the moon is really there and what triggers that phenomenon. My guess is that the moon is not really there but it's possible to access it by flying right trough to it.

02-12-2014, 09:28 PM
The whole time I was reading I was like.. Nooooooo it would have been too hot until... and then you said it and I was like, oh, okay, and I had to go back and re-read :P

The star: My concern is what the people of the CWBP2 world would associate with the star, depending on tech levels. How do they know it's old/dense? It'd be bright, right? If the people don't know much about stars, I think they might see the brightness and have fewer unpleasant associations? Maybe? (I did some google-browsing for inspiration and found only one "scary" reference... something about a comet/planet Hercobulus or something, that freaked me out, but it was unrelated...)

Do you mean special properties, as in magical?

(Also how long after the nebula is gone would stop seeing it? doesnt that take millions/billions of years? *confused*)

The Moon: I'm thinking hill spheres, which means I'm thinking she's not really there is the best way to go, because otherwise it would get caught up in one orbit or another, yes?

Maybe a thin rift/veil between the dimensions which you can see through only when conditions (or the planet itself?) is aligned a certain way?

02-12-2014, 10:16 PM
In my mind the extra moon was following the exact same orbital path as the real one, only at a different speed. So it clearly could not be in the same physical reality. What would make it even more interesting is the risk it might have of ever fully manifesting and causing a collision. In that case though we'd have to make pretty clear what exactly causes the fluctuation in the moons reality.

Or maybe, one moon could be here the other in another dimension and they both fluctuate between the two dimensions but one is more here and belongs here and the other belongs there.

On the star. I was sort of imagining it like visible disc in the night sky but not much brighter then stars in general. Just more surface area. But if we have i throwing off particle clouds it could obscure a much brighter entity. If the star is as bright as a full moon at night then its obviously going to wash out a lot of other stars, making the study of stars either astronomy or astrology more difficult. Reading the wikipedia, what if the white dwarf was old enough that it wasn't too far from becoming a black dwarf. Or maybe I'm just obsessed with Jack Vance. I guess not every star has to be dying to be interesting.

Or we could go for a brown dwarf as well but I was wondering if those might be too bright for our purposes. Another possibility is that our planet is orbiting a star that is itself orbiting a different star. As opposed to know where the other star is orbiting ours. Is that possible? Is there any point?

02-13-2014, 12:46 PM
I like most of those ideas.

Problem is, if we're orbiting star A, and star A is orbiting star B, then ... here how about a really bad picture...


Facts we know:

Star B has a larger hill sphere (and a stronger gravitational pull than Star A. If it didn't, Star A would not be pulled into orbit.

At some point in orbit, we would be between Star B and Star A.

In order for Star A to orbit Star B, Star B must have significantly more MASS. It will be bigger, probably much, much hotter.

So, when we reach that side of Star A... closest to star B, we would be scorched... All the heat from star A that normally supports life on our planet PLUS a lot more heat from Star B... probably twice what we get from Star A.

If Star B is not that big, it loses mass, loses it's pull, and Star A doesn't orbit.

If we move far enough away from Star B (meaning Star A has to move farther away too,) then we move out of range of the hill sphere (not for a planet, but for a star (A) of any significant mass) and Star A doesn't orbit.

If we're *too* close, or our star is too small/cool, then we get pulled into orbit around star B, instead...

It CAN be done, and maybe something with that could affect something like what we've discussed with the moons, but it would be VERY complicated. Not saying that's a bad thing, it could be fascinating, but I thought I should at least point it out.

02-13-2014, 03:11 PM
Heat is a problem, but given that it's 75AU away one night is more like a really bright dusk, there might not even be Ice caps. As far as the planet's orbit, it's good. it's got significantly more attraction to its star than the primary star. However, it'll experience some really crazy gravitational effects. Probably really intense tides. etc.

02-13-2014, 04:56 PM
fALCONIUS: a white dwarf is basically a dying star, it does not burn or fuse anything. It's just like the center of the Earth, it does not produce any energy, it's just cooling off.

The particles I was referring are several billion years old and should have dissipated but it's possible that some parts have agglutinated to form some magnetic clouds or something like that. Yes they could obscure the vision but they are located at specific places.

I'm trying to find how bright would be a star at around 75 AU. It seems the apparent magnitude of the Sun is around -17 :Apparent magnitude - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Apparent_magnitude) (It's brighter than a full moon)
but that's for the Sun and my idea was to have a much smaller star around. A good example of a white dwarf would be Sirius B, the twin of Sirius A, one of the brightest star in the sky. Sirius - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Sirius)
I have no idea how to calculate the apparent magnitude of our star.

some illustrative comparisons
File:Comparison sun seen from planets.svg - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/File:Comparison_sun_seen_from_planets.svg)
File:Artist?s impression of the surface of the dwarf planet Makemake.jpg - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/File:Artist%E2%80%99s_impression_of_the_surface_of _the_dwarf_planet_Makemake.jpg)

02-13-2014, 05:02 PM
Having the nearest star orbiting the other star is also possible. The difference in mass can be small. Alpha centauri A and B masses only have 21% of difference. Alpha Centauri - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Alpha_Centauri)

If they are far enough from each other, we won't have too many heating/gravitational problems I guess.

02-13-2014, 05:38 PM
Mkay. Just random musings... wanted to be sure if it would be a problem. (hadn't bothered to do the math)

I'm just wondering if the difference in mass (only 21% might still be millions of miles in size?) would affect how much heat hits our planet or howit would affect the orbit :P

02-13-2014, 07:32 PM
Yeah I was aware the White Dwarf was no longer functional, but they still last effectively forever. There's dead and really dead. I think we should probably just stick with what you had already worked out, I was just musing about different possibilities. I hadn't really read much on the subject before and the possibilities were all pretty interesting.

I am still concerned about the effect on star gazing. A full moon and something brighter than the full moon would completely wash out a night sky. These effects could be felt possibly for hundreds of years depending on relative locations of the star and planet. Maybe? As far as I can tell one side of the planet would have this orb hanging in the sky for a very long time since the orbit is so long.

Edit: We could I guess set the apparent magnitude to what ever we wish and then adjust the star to match.

02-13-2014, 09:51 PM
Ok let see the apparent magnitude is on a logarithmic scale. Every time the magnitude goes up by one, it mean the star is 2,5 times brighter. So... according to my maths and wikipedia... the apparent magnitude of the Sun is 400 000 times brighter than the full moon.

absolute magnitude : Sun 4.83 vs Sirius B 11,18
difference is 6,35 so it's something like 250 or 300 times fainter that the Sun and lets not forget than our star is 75 time further. but that just the absolute magnitude, the apparent magnitude is more important

the distance between the planet and the old star varies between 74 AU and 76 AU if we assume that the old star's orbit is a perfect circle....
Brightness varies inversely with the square of the distance

+ 1 magnitude: 2,5 times brighter
+ 5 magnitude= 100 times brighter
+ 10 magnitude = 10 000 times brighter
+ 15 magnitude: 1 000 000
+ 20: 100 000 000
+25: 10 000 000 000

now brightness depend on distance too, so to get the apparent magnitude I need the absolute magnitude (11,18). The distance used for the apparent magnitude is 10 parsecs or 206 260 AU. By using the Inverse square law, the square of 206 260 is 42 543 187 600. I think it means that the star is 42 543 187 600 times brighter with an apparent magnitude of about -16. Your at 1 AU and your about to fall in the star and it's dimer than the Sun as seen from Eris at aphelion ... So it's not very bright.

But since the planet is at 75 AU, we multiply the distance by 75 and divide the brightness by the square of 75 (5625). Which gives 42 543 187 600/5625= 7 563 233 brighter than the original magnitude (11,18). On the logarithmic scale, it mean a decrease by more than 17 units. 11,18-17,18= (yes, the lower the magnitude, the brighter the star)

-6 which is the apparent magnitude of the star as seen from the planet when the distance is 75 AU...
Look at the table to get an idea of it's brightness. Nearly 3 time brighter than Venus and 600 time fainter than the full moon.

02-13-2014, 09:59 PM
By comparison, Sirius A, the brightest extra solar star as seen from Earth is about 50-60 times dimer than our old star.

hum what a headache...

02-13-2014, 10:50 PM
Lol. I'll take your word for it. That apparent brightness sounds very reasonable.

According to Wikipedia, -6.5 is "The total integrated magnitude of the night sky as seen from Earth." So this star would be very apparent but not annoyingly bright. Although I would have thought the total integrated magnitude of the night sky would have been higher.... Guess because it's on a logarithmic scale maybe?

So if our extra star is a temperature about 5000-6000 k it would be yellow in appearance? Assuming that our main star ans solar system is similar to Earths then that would mean two yellow stars. I'd actually like to differentiate the colours between them more substantially than that. Say either one level down into orange or into a higher level to white or blue white. This way it would allow for mythical opposition in their associations between the two stars. Personally I prefer a darker colour for the natural threat that would seem to pose to our home star. The apparent colours are different though so I'm not sure if what I'm saying makes actual sense.

As you mentioned Azelor we should also consider what is around the White Dwarf as a result of its change of state. As far as I understand it it could be pretty much anything from planetary nebulae, to rings of debris, to gas clouds.

We should also put some thought into the rest of the solar system. What planets and how many are orbiting our sun? Are there any rogue planets on a long or weird orbit due to the influence of the second star? Are there any belts of crap in orbit with us? Etc.

02-13-2014, 11:29 PM
The star could be hotter than that, thus she could appear white or even blue maybe but I'm not sure it's possible to differentiate the color even with basic observation tools. It's more about radiations and for that you need much more advanced equipment. Anyway, if someone have the luxury to stare at the Sun long enough to figure what color it... become black

Light has no color in nature so does the stars I think. I'm not sure : File:Sirius A and B artwork.jpg - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/File:Sirius_A_and_B_artwork.jpg) But I prefer when they have colors
oh and the star would be about the size of Venus

02-13-2014, 11:44 PM
Erm... I feel like I am the rain and ya'll are the parade :(

But... (it didn't hit me until falconius said that he thought the magnitude of the night sky would be higher.)

Okay, the difference between total magnitude and apparent magnitude is that "total" is how bright it really is, and "apparent" is how bright we can see.

Cool. No big deal, we got this.

So, picture a star as a candle, or a torch or flashlight, or... whatever.

And over the whole space of the sky there's a billion stars, and over the country there's a billion candles/torches/flashlights.

All spread out, with maybe one big (moon) searchlight in the middle of the country, we see, from our airplane, a soft glow over the countryside. Pretty!

And in the sky we see lots of bright twinkling lights.


That is "apparent" magnitude.

According to Wikipedia, -6.5 is "The total integrated magnitude of the night sky as seen from Earth."

We're talking about TOTAL magnitude.

So that's all those stars and the reflected light of all those planets, and that big ole' moon all squashed into one space. All those lights and candles and torches all set on top of one building with that searchlight right dead in the center.

That's all those lights magnified.

That's hella bright. Like... blinding bright. But it says "as seen from earth" which (in the example of candles on a building would be "as seen from our plane") which is still hella bright, but not blinding. It *is* like daytime at night, though.

Which is cool... it could work into a great plot.

It would cause, I presume, a polar/alaskan sort of effect, where half the year there would *be* no night. Maybe a very slight dimming, but no night.

That's fine by me, if that's what you want, but that is what it would be like... Daytime facing one sun, nighttime facing another, till we got to the opposite side of the orbit and had night again. And during the "daytime at night" phase, the moon(s) and star(s) would be visible sometimes, just as they are here on earth... during the day.

And that would affect everything, tbh. The type of plants that could grow, the way they grow, nocturnal creatures would probably be migratory, if they existed at all, or they would be underground creatures. Sleep patterns, tides, and winds would be affected, there'd be no "cooling" nights, etc...

Could be interesting but it wouldn't be subtle at all.

02-14-2014, 12:23 AM
No, the night would still be dark with a star at that apparent magnitude. The sun as seen from earth is -26.74 and "Sun as seen from Earth (about 400,000 times brighter than mean full moon)." That is what it would take to light up the sky that much. A full moon is -12.29 and that does not make the night significantly brighter. You can see your way around in the dark but that is about all. -6 for our star is much smaller than even that so it would not have as serious effect as you are supposing. About the worst of it is that it could possibly be visible during the day given the right conditions.

Here's the wiki link I'm pulling my suppositions from. (http://en.wikipedia.org/wiki/Apparent_magnitude) From what I understand the ratings are not linear, but logarithmic? Which I think puts them on a curve meaning the meaning of the numbers changes more than they would seem to indicate.

02-14-2014, 12:26 AM
about the sky I think this will clarify things. That's how I understand it. Right and left should have the same total magnitude

10 stars with 0,1 magnitude and 1 star with 1 magnitude but on a linear scale :) so if you combine all the stars, you obtain that total magnitude. But since they use a logarithmic scale, faint stars contribute very little to the grand total and most stars are faint.

As said before I think, the light received by the star is only a bit brighter than the wold sky at night. It only means that it would be a little easier to see at night for humans at least ;). But the moon will probably outshine the star most of the time.

02-15-2014, 12:10 AM
Sirius B was a bad choice after all. It's a massive and young white dwarf, much brighter than our star should be. The Van Maanen's star would suit better. But the difference in apparent magnitude would be rather small since it's a logarithmic scale...

02-16-2014, 01:12 PM
Any other suggestions ?

02-16-2014, 10:04 PM
I'd say our star issue is settled. I'd like it to appear startlingly blue from the planet, due to however needs to be done, maybe an intervening nebula. The sole reason for this is because I'd love to refer to it as The Blue Star, or variations thereof (the ghost star, blue is a nice colour for imagining.).

Let's work on the planets. I want various godly aspects to be able to associated with the planets so maybe we can work backwards from that. Need Rage obviously lol, Love, ?the Dreamer? the planner? or the Scholar? the Fool? the Fox? Um... what else..

Also we can have some planets have sister planets around the other star, not that the people would necessarily know about them. They could be ravaged or whatever, but some G nodes may even be able to transverse space.

02-16-2014, 11:09 PM
Blue mean that the star is freaking hot, over 30 000K but blue white would be ok. Unless you want a neutron star ? She could have a temperature over 500 000K:o No it's a bad idea.

I while back I did some test with planets. Ours would be the 3rd or 4th. I guess the white one is a planet. There was a gas giant but it wasn't fitting.


02-16-2014, 11:35 PM
The star doesn't need to be actual blue but I want it to appear that way from the planet. Cause blue's cool. It could be because it's shining through some nebula it blew off when it died or maybe has a blue ring in orbit around it or whatever.

I count six planets in my proposed list, for Earth according to Wikipedia, there were five classical planets observable with the naked eye. I'm not sure I can read that solar diagram there, does it include moons? As only see four planet orbit rings.

02-17-2014, 10:12 AM
Yea, the last one is probably a planet.

02-19-2014, 12:44 PM
We should also indicate times. In terms of orbits, we are certainly going to need to know what a lunar month is, what a solar year is, what a phase month is (the orbit of the second moon), and probably what the orbit of the second star is (you said something like 500 years but it'd be nice to know). The orbits of the other planets can be whatever they come out as (unless someone has some specific plot ideas to use for them which require they be a certain way).

We might also consider what a common week is. The 7 day week on Earth is religious in origin and possibly lunar, though obviously that doesn't work out exactly. Our world could have 8 day weeks, 9 day weeks or whatever. I think however shorter than 7 days is too short of a week and 10 or longer is too long (why the French choose 10 days for their revolution is beyond me, why not 8 if you want easy calculations?). Obviously this would not represent all cultures but we should have a generally understood week that we default to when not otherwise specified.

Also how long a day is would be important to know to I'd guess, though any amount of time could be divided into 24 easily enough.

02-19-2014, 01:20 PM
I disagree about a 7 day period being too short of a week. I actually (when writing) tend to lean toward triads. (3 day weeks, or 3 week months, or both).

It seems logical since nearly every culture in the world (including most major religious sub-cultures) have at some point placed a degree of significance around the number 3.

So, usually, a "week" in my stories is "two triads" (6 days) and so on..

I also don't think (with the tech level proposed) that precise calculations of the days in a year, or weeks in a month, or even hours in a day makes much sense as far as /plots/ go... people at that age wouldn't know exactly how many days it takes to orbit the sun, ya?

As far as tides and such... climate.. whatever... I agree it would be nice to know exactly what we (the mappers) are dealing with :P

02-19-2014, 02:23 PM
People of the monolithic age knew exactly how long a solar year was, because they built devices to measure such things. Stonehenge being an obvious example of something that measures the equinox. Indeed I'd suggest study of the celestial workings is the first real scholarly pursuit of mankind. Celestial navigation is highly dependent upon knowing this sort of thing as exactly as possible. In a world where compasses don't work it would have remained so for even longer. The moon is even easier to track and observe because it is so large, and because of the relatively shorter times. All you have to do to know when the new month is is go at side and have a look-see at the moon and viola. In other words this type of celestial knowledge would be among the first discoveries of mankind on any planet with astral bodies to observe.

About the week, I wasn't suggesting 7 days was too short, but rather 6 days or less. And it is not an empirical observation just an opinion. The reason being that to actually get stuff done based on 6 day weeks, especially if one day is devoted to religious observance (quite common in ancient times). At weeks of even less days the problem merely becomes that much greater.

02-19-2014, 03:30 PM
Wellllll... some races did study the stars very early on, and a few were able to do so accurately. But most do not.

Then again, we'd probably all be working mostly with the more advanced peoples, yes ? :)

I also think it would be different if we had a less... regular... orbit. :P

But I'll concede that.

The weeks... most americans now have a 5 day *work* week, and manage to accomplish.... well... quite a bit, for americans.. :P

Add a religious day, and that's 6. ^.^ For others... again, (maybe my mind is just stuck in Ibala, and on tribal stuff?) many tribal peoples don't/didn't divide into 7 day weeks, but into MUCH shorter or longer periods of time. "Religious" days only happen with organized religion. Most organic belief systems focus on constant, every day/minute obeisance, and don't have a set day for worship. Then again, I suppose, if we're looking at more "advanced" (technologically) people, their religions might be more organized. They usually are on earth....

I'm not pushing for a 6 day week, just saying I think it's highly workable. Wasn't trying to argue/debate it, just adding observations :)

I'd also love an 8 day week... some sort of... infinity...symmetry... idk... I am weird. :/

02-19-2014, 04:19 PM
Stuff like this is probably better left to being figured out once civilizations/cultures start being developed. Better to build this stuff rather than pick it arbitrarily.

02-19-2014, 04:34 PM
Never mind the weeks, I'm sorry I brought them up, they are not that important. What is important is all the other stuff because those are absolute facts, not just shtuff we can make up on the fly. The planet will absolutely take a certain amount of time to go around its orbit, so will the moon, the second moon and everything else in our solars system. This is stuff that we can know with certainty. This is stuff anyone more advanced than hunter gatherers would know, and even most of them would either know or have a handle on the basics.

02-19-2014, 06:00 PM
Why not just make it 24 hours or something close to that? We're still dealing with humans here (right?) and if that's so, then we might as well keep the earthen day, as realistic or not as that'd be. As for seasons and stuff, I don't know.

02-19-2014, 08:02 PM
Yea, let's keep it simple. Avoid doing things differently just for the sake of doing something different.

The 7 days of the week are based on the lunar cycle. (28/4=7) Apparently it's not exactly 28 days, oh well...
It also have different meaning, religious and cultural but most of them are related to Christianity.

Most of these elements of our world are going to be Earth-like I suppose.

02-20-2014, 10:57 AM
Goes back way before Christianity, but that is besides the matter. Ok so our circumsolar orbit and our normal lunar orbit are the same as Earths so we can use that data instead of figuring it out. We'll just need to figure out the second moon, and the second star then really.

I say we increase the velocity of the second moon slightly so that it completes its travel around the world a maybe half a day or a day shorter. This is assuming of course that it is on the same orbital path as the real moon. So lets say our fake moon completes it's orbit at 26.5 days on the dot. We could also slow it so that it completes at 28 days on the dot. (for reference the earths moon takes 27.32 days)

02-20-2014, 11:39 AM
The main moon orbit the planet in about 28 days and the second moon is slightly faster on the same orbit? The second moon is still in another dimension I hope.

02-20-2014, 12:28 PM
That could still fit though?

02-20-2014, 01:33 PM
The main moon orbit the planet in about 28 days and the second moon is slightly faster on the same orbit? The second moon is still in another dimension I hope.

Yeah still in another dimension sort of, it adds some tension when the second moon risks manifesting too much. Ah... imminent planetary destruction really puts things in perspective.

02-20-2014, 11:10 PM
No, it's lunar destruction we are talking about. It's much less destruction and thus less interesting.
But what would happen if the two moons hit one another? Both moons get back in their dimension to disintegrate peacefully? Or they collide in the same dimension? Destroy the fabric of the world itself and provoke and even weirder phenomenon?

Well, I'm asking that question but I don't want it to happen. So it does not need to have a solid explanation. One could say: ''when I see that the moons are about to collide, I just close my TV and do something else. I try to convince myself that it's just how things are supposed to be but it's still really annoying to think that we are all going to die... again''. That's what I did in Zelda Majora's mask and I think it's a perfectly legitimate answer.

For the rest of the system, I will play with my physic simulator to test the brightness of the second star. It's on scale so I'll put a print screen here.

I said that the orbital period was around 500 years but I have no preference for the orbital eccentricity or the angle of inclination. Ideas?

AS for the rest of the system, my idea was to have:
1- planet that orbit close to the star. It is tide locked. I do not know at what distance a planet could become tide locked with the Sun but I suppose the planet would be difficult to see from our world. Maybe at dawn/dusk, a small and reddish sphere would appear in the sky close to the star. It's possible to see her only a very short moment in the best scenario. It's a lava type planet. Being close to the star mean it's a lot hotter with surface temperate well over 100 degrees on the tidal locked face. But the other side is freezing cold. And finally, the tidal energy generate heat in the planets resulting in a lot of geothermal activities. Maybe (would be cool) to have enough tectonic activities that the planet would generate a faint reddish light. The orbit is almost a perfect circle. It's about the size of Mercury.

2- is an old planet. The formation occurred before the supernova and before the main star was born. She probably drifted for some time in space before gaining the actual orbit. Her obit is pretty eccentric. Temperature on the planet are extreme since the rotation takes about more than 3 terrestrial years to complete and has a strong inclination. The planet has near to zero magnetic field given it's slow rotation and the small size of it's melted core. Is has a very thin atmosphere with different gases and water. During it's life, many objects came in collision with the planet. That's why there are so many craters and water in the atmosphere. There also a lot of debris floating around the planet. Some of them rotates at more than 1 million km but most orbit closer in a planetary ring. The debris are generally small or it's simply dust. The color is a pale gray and she is smaller than Venus. This planet would be visible with naked eyes.

3- Orbit pretty close to our world and is in the habitable zone too. It's an earth like planet that is 30% bigger and rotate in about 36 hours. The gravity is stronger which allows for a thicker and denser atmosphere. It's a very humid place but extreme climates also exist (but maybe not deserts). The planet is more inclined (30 degrees) so climates are more extreme between the season. It has 2 moons: the second one is pretty small but the closest one is much bigger, bigger than the moon. It's so big that the planet is tidal locked to it.

4- CWBP 2 world ...

5- a cold planet smaller than Venus orbit at around 250 millions km of the star. It's almost all covered with a thick layer of ice which reflect a lot of light into space.

6- a blue gas giant, probably made of methane.

I haven't sorted all the details

02-20-2014, 11:26 PM
I can't imagine two moons colliding that close to our world would leave it unscathed. Also lunar collision is pretty exciting and pretty damn interesting. I don't know what would happen if they actually did collide, it's not important, just the tension of the suspense is what I'm looking for. Can make for some interesting stories.

All three of those planets sound really great.

My concern is getting like 4 or 5 or 6 observable (with naked eye) planets so we'd still need one more, maybe a couple of gas giants? OR a big Ice planet. Then we can leave any further planets in the system for later or for people to put in on a by need basis.

02-20-2014, 11:30 PM
I just edited the message. The gas giant would be blue and cold like Uranus/Neptune. I don't know how far from the star it would be though, 3 AU ? There would still be some room for other planets.

02-20-2014, 11:50 PM
Would some sort of super dense planet be possible allowing it to have a very large ring? The idea being that it would be a small planet surrounded by enough stuff that it looked sort of like a dinner plate with a pebble in the middle....

02-21-2014, 01:04 AM
Maybe, the planet could be made bigger.

A couple of pictures (i know light comes from both sides equally as the software does not consider the stars brightness when it comes to light reflexion on planets)

1- both stars as seen from the first planet that orbit at 2.5 millions km of the main star.

2- Planet 3 and main star (more than 3 times the mass of Earth) as seen from CWBP2. I don't know if it's normal but it's the only planet I was able to see. It's about 20 millions km aways. Planet one and two should appear somewhere...

3- the old star compared with the moon

02-21-2014, 09:14 AM
Could we include a gas giant orbiting very close to the sun? That could make an interesting feature to the star system if it were large enough to cause visible (partial) eclipses.

02-21-2014, 11:17 AM
hmmm idk where to start...

1) A lunar collision is the secondary plot of my latest novel-in-progress, and the primary plot of the entire series in my head, so I agree with falconius... I think it's VERY interesting.

2) I think having 2 tidelocked planets in the system could have interesting results, but it would sounds rather uninventive to a lot of readers/players if we don't *do* anything with them. Also, I don't know how likely the chances of that happening.

I know that the more stuff there is going on in the system, the more ways people can use it, but idk where the outer limit of believability comes in. So far we have a solar system with a star rotating another star with a planetary system containing an earthlike planet that can support life, has 2 moons in different dimensions set up for possible future collision, 2 tidal locked planets, some very large moons, a second planet which just happens to be habitable if the moons do collide (or something else drastic happens nd our CWBP2 project becomes uninhabitabe, and everything is visible with the naked eye from the planet that just happens to support life.

Still plausible, if explained away properly, but it's really pushing boundaries of believability, i think.

4. The simulations look plausible though :)

5. Regarding a large gas planet near the sun... I tried some real basic calculations, with Jupiter about the distance of venus and kept coming up with impossible answers, so either it's impossible, or my math is really bad. Probably it's my math. Can someone smarter than me test what would happen? :)

6. I know this all sounds negative but I actually like nearly everything (I have like 80 gorgeous plot-lines spinning in my head already, lol) Just wanted to clarify I'm not against any of this, just trying to understand how far it can go :)

02-21-2014, 12:50 PM
I counted only one tidally locked planet, the other tidally locked object there is a moon for planet 3.

While planet 3 exist in the habitable zone and has weather patterns it is not necessarily supporting any life. The likelihood is not. Either way our population would have no idea whether there was life there or not. (unless we go with the idea of some G nodes leading off world.)

In Earth there are 5 classical planets that were easily observable with the naked eye. So far I count only 3 or four here, plus one that is very occasionally observable (planet 1).

We aren't even scratching the surface of our made up system when you consider our Earthly solar system has 8-9 planets that we know about, an asteroid belt, at least one protoplanet. Pluto is possibly a binary system with one of its "moons". And plenty of comets zipping in and out on strange orbits. I'd say given that all this cool stuff is really happening in our one actual solar system, having a really fun made up solar system isn't as half as strange as reality.

02-21-2014, 01:15 PM
oh i misreaad that about the tidal locked moon then...

I'm not saying we can't have a lot of stuff in the system, it's more about what the stuff *does*.

(And I'm old enough and stubborn enough that pluto will always be a planet to me ;P )

02-21-2014, 01:31 PM
I'm not saying we can't have a lot of stuff in the system, it's more about what the stuff *does*.Yeah I know it seems concerning, but I don't think it's actually something to worry about when in comparison to our actual solar system. Given the immensity of space and the countless possible things that can go on I doubt we can go to wrong to put lots of stuff into our tiny little creation.

(And I'm old enough and stubborn enough that pluto will always be a planet to me ;P )I'm not really convinced either way, but having grown up with it a planet my inclination is the same as yours. I don't quite agree with the Astronomers new definition of planets so much.

02-21-2014, 01:46 PM
If Pluto was still a planet by definition, there would be 10+ other planet in our system. Planets are supposed to have something special , they aren't just small rocks floating around. If it was so, one could consider large asteroids as planets too. But that's another debate in the same line as the tomato debate...

I did not considered putting a gas giant close to the star mainly because our solar system don't have one... Maybe they can't form too close but I'm not sure. How close could it be? One could say that considered the size of the system, Jupiter is pretty close to the Sun.

02-21-2014, 02:22 PM
A gas giant can form as close as you want it, really. WASP-18b is only a little more than .02 AU from its star, and it's probably around 10 times the mass of Jupiter.

02-21-2014, 02:48 PM
What's the mass of it's star, though?

I'm a bit concerned if the mass is too great compared to the mass of the star, it wouldn't be able to hold an orbit very close to the star.

Also, if it was too hot, what the effect on the chemical reactions would be.

I'm just supposing, though... I haven't looked into any data, so if you do know, then please share :P

And, like I said, I'm cool with the planets I have, and I'd even be cool with more. I don't think eveery planet needs something unusual... we've got uranus and neptune which are rather blah (imo) as far as planets go, for example. But I'm not opposed to it either. Was just pointing out the apparent statistical unlikely-hood... key word being "apparent"... I'm trying to force myself to look at believability 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 :P

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

02-21-2014, 03:09 PM
All of this stuff is unlikely to come up often if at all. While it allows a creator to add depth to the world and the things we make for it, all of these "stuffs" are not going to be overtly explicit in our stories or modules or whatever. Unless of course the plot deals with them directly, but even then I don't think their "believably" will be called into question. The amount of stuff going on here is only noticeable because we are dealing directly with it in creation and in its definitions. Not many people read encyclopedias cover to cover. And fanatics who are obsessed with minor continuity errors and slight realism errors in a fantastical world are pretentious and silly.

02-21-2014, 03:13 PM
Not many people read encyclopedias cover to cover. And fanatics who are obsessed with minor continuity errors and slight realism errors in a fantastical world are pretentious and silly.

I feel like you're talking about me D: I do this things :?

You're right, though, it prolly won't come up at all. and I'm just being annoyingly nitpicky, so Imma shuttup for a while :P

02-21-2014, 03:35 PM
I feel like you're talking about me D: I do this things :?lol I'm sure this forum in general attracts people who do these sorts of things. The thing is though whether these errors get in the way of the story or not, when they don't and one searches for them anyway the person is in essence denying the medium for what it is. When you are more concerned with whats going on behind the scenes then the scenes themselves that is a problem. But crowds aren't interested in buying tickets for a behind the scenes documentary for a reason, especially not without seeing the movie first.

02-21-2014, 03:44 PM
once again,I am weird, I usully prefer the "how it was made"than what they made :P

but i see your point.

I think I am paranoid because sci-fi and mid/high fantasy fans (both readers and gamers) are more likely to pick than any other genre (including historical fiction, which is.... weird, you'd think history fans would demand more accuracy...)

But I'm cool with all we have here... was just... pointing :P

02-22-2014, 01:51 PM
What's the mass of it's star, though?

I'm a bit concerned if the mass is too great compared to the mass of the star, it wouldn't be able to hold an orbit very close to the star.


WASP-18 is an F6 star with an apparent mass about 25% greater than the sun. It's a little bit larger and a little bit hotter than our star, but it's reasonably Sun-like. WASP-16b will probably collide with the star eventually. If it's been spiraling inward for a long time, it may have swept up many of the other planets in that system as it did so: sending them into larger orbits, hurling them into the star ahead of itself, or even absorbing them.

How the presence of a large planet that close to the star would affect potentially life-harboring planets further out is an interesting question. That particular planet would probably block less than 10% of the light coming from the star for maybe half an hour each day (that's a wild guess; I only did some very rough math), which would only slightly reduce the total solar power reaching the biosphere. Even a small change of that kind could have large ramifications, though. The regular partial eclipse would be a noticeable event. Might make for some interesting mythology.

A large planet further away from the star would make the eclipses longer and more dramatic, although less frequent. It might also have the effect of perturbing the inhabited planet's orbit, though.

03-10-2014, 11:35 PM
I'm not opposed to the idea of having a gas giant in the inner system and the impact would be small. Unless the planets are close to each other and/or their obit have the same angle of inclination, the Gas giant will have no negative impact.

04-02-2014, 02:36 AM
K, here's what I have so far then (Azelors orginals will be tagged [A]):
Our star
Planet 1: [A] Tide locked, close to sun
Planet 2: [A] Old drifter, much orbital debris
Planet 3: Inner gas giant
Planet 4: [A] Earth-like but 30% bigger, orbit close to CWBP 2, two moons
Planet 5: CWBP 2 planet
Planet 6: [A] Ice rock smaller than Venus
Planet 7: [A] Blue gas giant
Planet 8: Somthing to just finish up the system, I think one more would be nice

and the Second star with associated nebula and possible planets to be filled in at a future date.

04-02-2014, 09:21 AM
Add one more gas giant, at a far away orbit but close enough so that all 8 other planets will be visible from the homeworld. That way there'll be 9 "wandering stars" known to the people (the secondary sun counts as the 9th), which gives them a nice number to feature in astrology.

04-02-2014, 03:54 PM
Add one more gas giant, at a far away orbit but close enough so that all 8 other planets will be visible from the homeworld. That way there'll be 9 "wandering stars" known to the people (the secondary sun counts as the 9th), which gives them a nice number to feature in astrology.

and I assume that would be our 8th planet.

The second star is so dim that one or two planets would be brighter but only at their brightest. You see, their brightness will fluctuate a lot depending on their position. On the other hand, the second star will have a variation of only 7% luminosity due to the movement of the planet around the main star. This is considering that the second star is still at 75 AU from the main star. 75 AU (or 11 175 billion km) is what I considered a safe distance that allowed both stars to have their own system. Of course the orbit could be elliptical but I assume that if it's the case, 75 AU is the average distance. That would also influence the brightness perceived from the planet... but these are just details

Planets from the second star (if any) would be impossible to spot in the sky with the available technology. But they are free for speculators.

04-02-2014, 04:12 PM
and I assume that would be our 8th planet.

No, I meant add a 9th planet in addition to whatever will be placed on the 8th spot. So there'd be a total of 9 planets (8 from the POV of the people living on the homeworld planet), which would probably be regarded as moving stars. As would the secondary sun.

04-06-2014, 03:35 AM
Planet 1: [A] Tide locked, close to sun
Planet 2: [A] Old drifter, much orbital debris
Planet 3: Inner gas giant
Planet 4: [A] Earth-like but 30% bigger, orbit close to CWBP 2, two moons
Planet 5: CWBP 2 planet
Planet 6: [A] Ice rock smaller than Venus
Planet 7: [A] Blue gas giant
Planet 8: Maybe a large terrestrial planet, probably some sort of ice planet?
Planet 9: Gas giant

The Second Star

04-13-2014, 04:28 PM
Hi guys I like where this is going. I probably won't be able to wiggle participation in this project back into my new therapy schedule though so I won't start joining in the planning again until/unless I know for sure.