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Andi K.

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Posts posted by Andi K.

  1. 45 minutes ago, Hypercosmic said:

    Interesting...

    So, what do you expect Proxima b to have? Having lots of volcanoes, basalt plains, cracks, fissures and ravines, and an ash-filled thin atmosphere composed of CO2 plus other common volcanic gases, maybe? Because a plain-looking planet won't do.

    Well that's the thing, perhaps being in a spin-orbit resonance prevents such extreme geological activity to occur from tides.

  2. On ‎6‎/‎29‎/‎2018 at 9:32 AM, Hypercosmic said:

    Mercury is actually pretty far from the Sun. :/ (Note: Mercury's semi-major axis is roughly 0.4 AU (e=0.2), while Proxima's is roughly 0.05 AU. Proxima is also larger than Mercury, which means more tidal effects)

    Also, if my understandings are correct, you don't really need a third body to pull on Proxima Centauri b for it to experience tidal heating. The difference in tidal forces acting on it at periapsis and apoapsis, combined with the planet's rotation, might be enough.

    What's Proxima b's eccentricity in your mod, by the way?

    Nevermind, I'm dumb. You're right in that you don't need a third body. However, when looking at Proxima b's small sma, you have to remember that Proxima itself is much smaller and much less massive than the Sun, so it is kind of hard to compare the two. I'm going to calculate the change in the gravitational force between periapsis and apoapsis for both Mercury and Proxima Centauri b to get an idea of the kind of tidal heating that is experience on Mercury compared to Proxima b.

    Proxima b: 2.22e+24 N

    Mercury: 1.16e+22 N

    Basically, the change in the gravitational force for Proxima b is greater than that of Mercury. So, you're right. Proxima b would probably experience way more tidal forces that Mercury, despite Mercury orbiting a much more massive star. I'm not totally convinced that this would result in some sort of volcanic planet, though. Are there actual scientists that have written about how geologically active Proxima b would be?

    EDIT: @Hypercosmic It would seem to me that, although Proxima b experiences great variation in the gravitational pull from Proxima, a 3:2 spin-orbit resonance would mitigate this to some level I think. The variation in the gravitational force would cause the planet to deform, causing the planet to heat up. However, a 3:2 s-o resonance is a more gravitationally stable configuration, and would lessen the amount Proxima b deforms. This would make tidal heating less extreme, and lower the amount of friction occurring inside the planet. I don't have any studies to back this up, that is just what I'm guessing.

  3. 9 minutes ago, Hypercosmic said:

    I heard that to get stuck in 3:2 spin-orbit resonance, your planet needs to be in a rather elliptical orbit, and that would probably cause quite a lot of tidal heating and thus geological activities. Volcanoes and dust-filled atmosphere would make some cool scenery, and seismic activity for good science without having to carry a bomb with you.

    Still expect a few fresh new craters though.

    I don't think that what your saying is entirely true. Yes, you need to be in an elliptical orbit in order to get that resonance, but that doesn't translate to more tidal heating. Look at Mercury. Does it have much geological activity from tidal heating? No. Another planet/moon would have to be pulling on Proxima Centauri b in order for it to experience tidal heating.

  4. On 6/28/2018 at 7:26 AM, Hypercosmic said:

    There we go, Proxima b looks more awesome now. Though, I expect a few large craters, but I guess those are eroded by the eternal storm caused by the temperature difference between day side and night side.

    Oh, speaking about night side, I wonder if any atmosphere on this planet would freeze there...

    There are craters there, but they are eroded from the atmosphere and the water that used to exist on its surface. Proxima Centauri b is actually not tidally locked here. It is in a 3:2 spin-orbit resonance, like Mercury.

     

    On 6/28/2018 at 8:21 AM, The Minmus Derp said:

    1. Yay!

    2. Of course.

    Come to think about it, I'd actually prefer you don't make an expansion for REX.

  5. 28 minutes ago, The Minmus Derp said:

    Cool! Muns?

    As I've said previously, no moons will be added into Real Exoplanets. The mod is called Real Exoplanets, and thus far, we have not discovered any moons outside of our own solar system. If I added exomoons into REX, I'd basically be forgoing the whole "real" aspect of this mod, which is basically the entire point REX.

  6. 29 minutes ago, ProtoJeb21 said:

    Whenever I open up Steam and click the "Play" button for KSP, I get a little window for what specifically I want to launch. Usually it's "Play Kerbal Space Program" and "Launch KSP (64 btit)" but since 1.4 was released the latter is replaced by "Launch KSP (32 bit)". With it, I cannot run the game well with mods or my giant 8 km long superlaser I made with TweakScale and BD Armory (I was bored). I can't even run the game with the smaller 1.6 km version or even the 200 meter version.

    If you go to the KSP folder, there should be an an exe titled something like "KSP x64.exe." Just launch it from there.

  7. 23 minutes ago, ProtoJeb21 said:

    Should I just keep this for my Exoplanet Explorers Pack (if I ever return to Kopernicus) or could this be used for Real Exoplanets?

    This definitely seems like an interesting system to add into REX, but if you want to put it into your Exoplanet Explorers Pack, you can go right ahead.

    By the way I'm very happy that I have a nice acronym for Real Exoplanets, unlike Extrasolar.

  8. 2 minutes ago, ProtoJeb21 said:

    Maybe 0.3 to 0.4 atm would be better, along with no more than 25% surface water. The thin atmosphere and high gravity would make it an interesting challenge to land on and take off from. 

    I kind of agree more with @Hypercosmic. Finding surface water should be something that is rare and exciting. Having the first planet you will likely travel to be one that has water and an atmosphere doesn't really translate to "rare."

  9. 9 minutes ago, Hypercosmic said:

    Tbh I can't imagine Proxima b having any significant atmosphere and surface liquid water. The planet gets constantly blasted by CMEs several times a month, and I don't think a habitable zone terrestrial planet could produce a magnetic field strong enough (thousands of times as strong as Earth according to [1]) to deflect its parent red dwarf's CMEs.

    I think having fewer 'Earth-like' planets is better. It makes a discovery of surface liquid water on a rocky exoplanet more rewarding.

    I am diving into the fields I'm not good at, so if you find something I stated wrongly, please notify me.

    Trying to cite my sources unprofessionally:

    [1] iflscience article

    [2] paper (link found in [1])

    [3] space.com article on Proxima b's atmosphere

    Yeah I'm just trying to be a little optimistic. I'm well aware of how it is more than likely that Proxima Centauri b is simply a boring, irradiated piece of rock endlessly circling Proxima Centauri. In fact, I think I've read those articles you cited before. For the sake of realism, I'll have to completely change Proxima Centauri b into an atmosphere-less world. Looks like I've gotta find another planet to use that texture for... I do agree though, the Earth-like planets should be very rare, so it is more rewarding when you find them. I might only add one planet that actually has life on it.

  10. 18 minutes ago, ProtoJeb21 said:

    I think now we can just about firmly say that Proxima b is dead. I used to think that the threat of flares were overdramatized, but with all the recent powerful flares that have been observed from Proxima Centauri, I’m finally starting to doubt in the planet’s potential habitability. @AndrewDrawsPrettyPictures If you want to have a good nearby potentially habitable planet in Real Exoplanets, I would recommend Luyten b. Assuming a perfectly on-edge orbit (a pretty generous assumption), it’s only about 2.9 times the mass of Earth, which, with an Earth-like composition, would give it a radius of about 1.35 R_Earth. It gets only 6% more sunlight than Earth and has a moderately eccentric orbit of e=0.10, keeping it within the habitable zone year-round and maybe preventing it from being tidally locked. There’s also a hot Earth-sized planet in the system as well. 

    EDIT: The system GJ 3323 could be a good system to use as well. While further away than Luyten’s Star, the innermost planet is just twice the mass of Earth and gets 1.17 times more sunlight than Earth according to my calculations, compared to 1.21 times for Luyten b. However, GJ 3323b has an unusual eccentric orbit of e=0.28, which would cause the planet’s stellar flux to range from twice to three-quarters that of Earth’s over its 5.4-day year. The second planet, GJ 3323c, could be a rare icy Super-Earth. 

    Oh Proxima Centauri b is is no way habitable in REX, despite having water and an atmosphere. The description for Proxima Centauri b is decieving, as I forgot to change it, and I'm pretty sure I forgot to remove oxygen from Proxima Centauri b's atmosphere. Do you think that Proxima Centauri's flares are so insane that there wouldn't even be a chance for Proxima Centauri b to even have any sort of atmosphere?

  11. 8 minutes ago, Hypercosmic said:

    Wow, that's quite something. Very impressive, gotta love to be able to explore the pressure ice layer below.

    Speaking of ice, at which depth do you expect the water to 'freeze' from pressure? Would that affect the planet's expected radius?

    I guess it would effect the overall density of the planet, and therefore influence what it's radius would be, but a lot of these numbers are speculative and/or fuzzy anyways, so it's not like it's a huge deal if we do not account for pressure-frozen water.

    Also, KSP considers the radius of a planet to be from the center of the planet to "sea level" (in this case the surface of the ocean) so changing the depth of the water doesn't actually influence the radius of the planet if that makes sense.

  12. @The Minmus Derp If you could also edit out the duplicate message, that would be great.

                                                                                                            

    I did some intense calculating based off of the numbers @ProtoJeb21 provided for Tau Ceti e, and everything checks out. Through those calculations, I determined that Tau Ceti e's ocean should be 5,157 km deep, and the radius of Tau Ceti e's mantle and iron core should be 7,266 km. This is perfectly in line with what would be expected from an water-world. This means that Tau Ceti e's ocean will be about as deep as Earth's radius.

  13. 1 minute ago, Hypercosmic said:

    Can't see it having a planet teeming with life at the same level as Earth either, but I'm more interested in how compact it is and each planet's properties. We know a lot about them.

    I think that in this system apart from b, c, all planets but e are probably lifeless ocean/icy rocky planets, while e itself might be volcanic bigger Mars.

    What I mean is that given the TRAPPIST-1's small size compared to it's planets, and the system's close proximity to Earth, it makes it an ideal system to analyze the atmospheres of exoplanets.

    Not that we're going to find life on any of them.

  14. 3 hours ago, The Minmus Derp said:

    Yay! Was Gliese 667C in the original?

    No it wasn't. Given the amount of stars in that system, I'd have to use sigma binary to get the star system to work properly. Unfortunately, I believe I've had problems with sigma binary and this mod.

    2 hours ago, The-Doctor said:

    Oh wow, so like, this is awesome. It says 1.3.1 though, but says updated in 2018, is this correct? Is this for 1.3.1 or is it the mod version? 

    The mod is for version 1.3.1 of KSP. 0.1.1 is the mod version.

                                                                                                            

    Hey guys, Tau Ceti e is turning out really well. If you look closely at the second screenshot, you'll be able to see Proxima Centauri and Alpha Centauri next to each other, and the Sun some distance above the two.

    tzbjJaX.png

    Jffzuht.png

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