If Kapteyn’s star has no life, why not? If it has, why haven’t we seen evidence?

One curious question is, are we alone in the Universe? Most people would say there must be others there, but there has been one disturbing thought recently, in that two planets have been found around the red dwarf Kapteyn’s star, which happens to be about rather close to us, at about 13 light years distance, and which also was formed about 11 billion years ago, and hence is almost two and a half times older than our sun and planetary system. One of these planets is in the habitable zone, so the question is, if it is habitable, and if life has a reasonable chance of being generated, why don’t we see evidence of it around this star? Perhaps a civilization is rare. Perhaps civilizations exterminate themselves after so long. Perhaps civilizations keep themselves secret. Perhaps something else is why we see no evidence, such as radio signals.
Rather intriguing is its proper motion; it was about 11 light years distant about 11,000 years ago. The reason for this is that it is orbiting the galaxy in the opposite direction to us! Galaxies grow by accreting galaxies, and our galaxy has apparently swallowed a small galaxy, some of which may be known now as the Omega Centauri cluster. One characteristic of this star is that it is rather short of elements heavier than helium. All such elements are made in supernovae, and then thrown into space. The younger the star, the fewer such supernovae to feed them.
The planets have been found using the Doppler method, which measures small variations in velocity of the star as it wobbles due to the gravitational tugs of planets. This star has a mass of about 0.28 times that of the sun, and a small mass and close planets make such detection easier. The two planets are (b) at 0.168 A.U. from the star, and at least about 4.5 times Earth’s mass, and (c) at 0.311 A.U. from the star, and at least about 7 times Earth’s mass. (The “at least” is because what is measured is msini, i.e. the actual tug that we see is the component in our directions, and the angle of the orbital plane is unknown.) An A.U. is the distance from the earth to the sun, and because the red dwarf is cooler than our sun, (b) is in the so-called habitable zone. Unfortunately, the news media then proceeded to make claims that were unjustified. The planets were described as “rocky planets”, and in some cases sizes were calculated. The fact is, all we measured was the gravitational tugs of the planets, and since the value of a sine is less than 1, the given sizes are minimum sizes.
However, the natural question was, with over 11 billion years for life to evolve, would it? If it would, with an extra 6.5 billion years, why hasn’t its technology led to space travel to us? What I find surprising is that so far I have yet to see anyone claim that it could be the source of UFOs. Some might also claim that since we have not been visited, the absence of such visits proves technical life cannot get into space, which again would be wrong and illogical.
If you accept my theory stated in my ebook “Planetary Formation and Biogenesis”, the answer is reasonably clear: these are not rocky planets, and (b) is unsuitable for life to form. Therefore, no UFOs, no radio signals, no life. A characteristic of the standard theory of planetary formation is that you start with planetesimals, but nobody has the slightest idea how they form. My view is different: accretion depends on chemistry (and yes, I, being a chemist, am biased), and what happens in turn depends on temperature. The temperature at a point in the accretion disk depends on the potential energy lost getting to it, which depends on the radial distance from the star, and the rate of the starwards component of matter flowing through the point, which, from observation, is very roughly proportional to stellar mass squared. Accordingly, the radial distance for equal temperatures will vary between accretion disks proportional to stellar mass cubed, plus or minus a lot. One complicating factor is less the energy radiated by dust and heavy gases, which will vary depending on the shape of the accretion disk. If we assume my approximate relationship, then the Jupiter equivalent should be at 0.12 A.U. and the Saturn at 0.20 A.U., both plus or minus quite a lot.
If so, we do not have rocky planets. The planet (b) is 1.4 times further out that where Jupiter is expected, and (c) 1.55 times that expected for Saturn. That could be expected because less heat would be radiated (because there is less dust to radiate it) hence a given temperature would be reached further from the star. In my theory of planetary formation, these two planets would be interpreted as the cores of the Jupiter equivalent (formed like a snowball by ice sticking together near its melting point following collisions) and a Saturn equivalent (formed by melt fusion of methanol/ammonia/water near that eutectic temperature, the energy of the collision providing the heat, the melt then fusing the ice.) The reason they would not develop to full gas giants would be simply a lack of material to grow that big. Of course such dust as was available would also be incorporated, and the resultant planets would be like a giant Ganymede and a giant Titan. Thus I would expect (b) to have little atmosphere but maybe be a waterworld on the face tidally locked to the star, and (c) to have a nitrogen atmosphere, and maybe methane. Why maybe? Because methane is photochemically degraded, and presumably has to be regenerated on Titan. On Kapteyn c, with 11 billion years photochemistry, the methane may not have lasted. There would be no life on (b), nor for that matter in any Europa under-ice ocean, because of a general deficiency of nitrogen, and also a probable difficulty in forming phosphate esters.

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