Exoplanet Populations and their Dependence on Host Star Properties
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Massive stars are more likely to host fewer planets in general as compared to lower mass stars.
High metallicity stars stars are more likely to host giant planets, low metallicity high mass stars tend to host some giant planets. Low mass low metallicity stars typically don't host giant planets.
hypothesis: the metallicity of a host star is likely to be similar to the metallicity of the star the hosted planet evolved from. Low mass low metallicity stars are more likely to turn into smaller planets. High mass high metallicity stars are more likely to turn into larger planets.
This is, if it is the case that proto stars will evolve into main sequence stars of different masses and metallicities according to their environment. So for example, a proto star may evolve to become a yellow dwarf, or larger white star, or blue giant depending on how much mass it gains from the nebula it forms in and depending on metallicity. In some areas such as globular clusters and dwarf elliptical galaxies, main sequence stars are more likely to be less massive and lower metallicity.
( In the standard model, on the other hand, this correlation is attributed to core accretion effect. "It has been established that the increased occurrence of giant planets around high-metallicity stars arises because giant planet cores are more likely to form in disks with a larger amount of solids" ...
("These trends, however, breaks down for planets smaller than Neptune, hereafter sub-Neptunes, which poses some urgent questions about the planet formation process. Why is the frequency of sub-Neptunes almost independent of stellar metallicity, even when the initial inventory of condensible solids must have varied by an order of magnitude? " )
Ideas for replacing the terms birth, death and life of a star:
"Lifecycle" doesn't hold as much of a connotation of a living organism as "life". Birth can be called activation. (The growth or formation of a star and planet is an ongoing process of transformation and evolution, not just its "birth"). For death, the activity of a star or planet is extinguished, an extinction. Remains are "reborn" or reactivated / reformed into new stars.
( Not that the poetic language of life, birth, death etc. necessarily needs to be replaced.)
In this lecture,Dr. Michael Shilo Delay asked for suggestions to replace the terms life, death, birth, etc for stars and planets. I believe Jeffrey Wolynski has mentioned this before in videos too.
Planet Formation, Aging Stars p.1 - The Stars (wk 6.1) Dr. Michael Shilo Delay
https://www.youtube.com/watch?v=4u1LXHWWtr4&list=PLDyAuNyQ5Gj1X_jPu1GQGZQjMFQGfZozM&index=10
and for good measure, here is Daniel Archer's paper "Stellar Metamorphosis Obeys the Natural Law of Birth, Growth, Degradation and Rebirth, or a New Law!":
In each ensemble, all 6 star members could have ignited at roughly the same exact time. The energy from a pair igniting can affect nearby pairs, and gravity will keep partners close by for the most part.
Stars form in pairs like peas in a pod, with the closest ones most commonly grouping together as gravitationally bound pairs of pairs, or three pairs, or sometimes four. This is not to say we should only expect to ever see quartets, sextets and octets, but they are very common in systems that we have observed, and quartets and sextets are common in our solar system. For larger more compact star clusters there could be much larger related ensembles.
On planets like Earth that were completely covered in water at an earlier stage, we may expect that life developed on a wide variety of environments before the dry land of the crust first appeared above the surface of water.
Besides in the water itself, life could have developed on and beneath the sea floor, in sea caves with portions that are not covered in water, on ice bergs, ice shells like that of Europa, glacial ice caves, floating islands of plants or "pumice rafts", and so on.
When interpreting ancient life forms and previous geological ages, we should be cautious about jumping to conclusions about lifeforms that may have lived in a dry terrestrial environment. Just because an organism can dig or walk or thrives in an environment that is not fully aquatic does not necessarily mean that an exposed dry surface of the continental crust existed yet.
An animal with lungs that breathes air does not require dry land masses yet- a lungfish can swim up to the surface of the water without any dry land exposed to breathe the air of the atmosphere. The existence of animals with lungs and legs do not mean dry land was necessarily present yet.
There is an assumption in the standard model that dry land was there all along for animals to just walk onto. This assumption is no longer supported and geology and biology must take into account Wolynski's Elysium transition of when dry land first appeared on the Earth.
Also worth noting here: it is hypothesize that in the ice shell of Europa, we may find something like isolated pockets of water similar to lakes and rivers embedded in the surface of the ice. This is another interesting type of environment to consider for the development of life. Earth, for example, may have gone through an ice-world stage where the outer surface of the worldwide ocean was frozen over.
A floating island is a mass of floating aquatic plants, mud, and peat ranging in thickness from several centimeters to a few meters. Sometimes referred to as tussocks, floatons, or suds, floating islands are found in many parts of the world.
A pumice raft is a floating raft of pumice created by some eruptions of submarine volcanoes or coastal subaerial volcanoes.
Pumice rafts have unique characteristics such as the highest surface-area-to-volume ratio known for any rock type, long term flotation and beaching in the tidal zone, exposure to a variety of conditions, including dehydration, and an ability to absorb many potentially advantageous elements/compounds. For at least these reasons, astrobiologists have proposed pumice rafts as a possible ideal substrate for the origin of life.[1]
Biologists have suggested that animals and plants have migrated from island to island on pumice rafts.
Jeffrey Wolynski - Stellar Metamorphosis - The Elysium Transition:
https://vixra.org/pdf/1808.0590v1.pdf
https://en.wikipedia.org/wiki/Floating_island
https://en.wikipedia.org/wiki/Pumice_raft
https://en.wikipedia.org/wiki/Lava_balloon
https://en.wikipedia.org/wiki/Glacier_cave
https://en.wikipedia.org/wiki/Benthic_zone
https://en.wikipedia.org/wiki/Benthic_fish
https://en.wikipedia.org/wiki/Troglofauna
https://en.wikipedia.org/wiki/Subterranean_fauna
https://en.wikipedia.org/wiki/Stygofauna
"JuMBOs"
https://www.space.com/jumbos-rogue-orion-nebula-star-systems
https://public.nrao.edu/news/astronomers-discover-jupiter-sized-objects/
https://www.theguardian.com/science/2023/oct/02/jumbos-jupiter-mass-binary-objects-discovery-orion-nebula-new-astronomical-category
https://infinitecosmology.blogspot.com/2019/
Star types today are still referred to as "early" for hotter more massive stars, and "late" for cooler less massive stars. A holdover from when Kelvin and Helmholtz understood that hot massive stars cooled and lost mass to become smaller cooler stars. Later, in an effort to force the age of the Sun to match the age of the Earth, a nuclear interpretation of the energy of the Sun was adopted, but "early" and "late" star types are still used.
The Kelvin-Helmholtz mechanism is still understood in the standard model to occur on Jupiter, Saturn and in general brown dwarfs, in the later stage, which cooled from the earlier stage of large hot stars.
https://en.wikipedia.org/wiki/Stellar_classification#Spectral_types
https://en.wikipedia.org/wiki/Kelvin%E2%80%93Helmholtz_mechanism
Stars are often referred to as early or late types. "Early" is a synonym for hotter, while "late" is a synonym for cooler.
Depending on the context, "early" and "late" may be absolute or relative terms. "Early" as an absolute term would therefore refer to O or B, and possibly A stars. As a relative reference it relates to stars hotter than others, such as "early K" being perhaps K0, K1, K2 and K3.
"Late" is used in the same way, with an unqualified use of the term indicating stars with spectral types such as K and M, but it can also be used for stars that are cool relative to other stars, as in using "late G" to refer to G7, G8, and G9.
In the relative sense, "early" means a lower Arabic numeral following the class letter, and "late" means a higher number.
This obscure terminology is a hold-over from a late nineteenth century model of stellar evolution, which supposed that stars were powered by gravitational contraction via the Kelvin–Helmholtz mechanism, which is now known to not apply to main-sequence stars. If that were true, then stars would start their lives as very hot "early-type" stars and then gradually cool down into "late-type" stars. This mechanism provided ages of the Sun that were much smaller than what is observed in the geologic record, and was rendered obsolete by the discovery that stars are powered by nuclear fusion.[69] The terms "early" and "late" were carried over, beyond the demise of the model they were based on.
The Kelvin–Helmholtz mechanism is an astronomical process that occurs when the surface of a star or a planet cools. The cooling causes the internal pressure to drop, and the star or planet shrinks as a result. This compression, in turn, heats the core of the star/planet. This mechanism is evident on Jupiter and Saturn and on brown dwarfs whose central temperatures are not high enough to undergo hydrogen fusion. It is estimated that Jupiter radiates more energy through this mechanism than it receives from the Sun, but Saturn might not. Jupiter has been estimated to shrink at a rate of approximately 1 mm/year by this process,[1] corresponding to an internal flux of 7.485 W/m2.[2]
The mechanism was originally proposed by Kelvin and Helmholtz in the late nineteenth century to explain the source of energy of the Sun. By the mid-nineteenth century, conservation of energy had been accepted, and one consequence of this law of physics is that the Sun must have some energy source to continue to shine. Because nuclear reactions were unknown, the main candidate for the source of solar energy was gravitational contraction.
However, it soon was recognized by Sir Arthur Eddington and others that the total amount of energy available through this mechanism only allowed the Sun to shine for millions of years rather than the billions of years that the geological and biological evidence suggested for the age of the Earth. (Kelvin himself had argued that the Earth was millions, not billions, of years old.) The true source of the Sun's energy remained uncertain until the 1930s, when it was "shown" by Hans Bethe to be nuclear fusion.
for more information: Stellar Metamorphosis
https://vixra.org/author/jeffrey_joseph_wolynski
