Talk:Formation and evolution of the Solar System

Angular Momentum in Pre-Solar Nebula

The article doesn't explain what caused the initial angular momentum in the pre-solar nebula. If gravity was the only force acting in the early stages of solar system formation, wouldn't material in the proto-cloud simply have flowed inward toward an expanding gravitational center? Virgil H. Soule (talk) 17:59, 21 August 2012 (UTC)

Only if the pre-solar nebula were perfectly still and collapsed directly. However, there are random motions in any star forming cloud (they're highly turbulent beasts) which means the gas has angular momentum when compared to the gravitational center. Just a little bit of random motion a large distance from the gravitational center is a lot of angular momentum. I'm not sure how or where this should go into the article, and I don't have an immediate ref, though one should be pretty easy to find. —Alex (ASHill | talk | contribs) 00:15, 22 August 2012 (UTC)

It does not explain what caused the initial angular momentum in the pre-solar nebula because they do not want to bring attention to the falsification of their model with basic physics. If there is angular momentum (and there is a hell of a lot of it in the objects that orbit the Sun), then how exactly is the angular momentum mostly in Jupiter and Saturn, and the mass mostly in the Sun? If any spinning disk model or theory of solar system formation were correct, then the Sun should possess the most angular momentum and the outer objects should possess very little, but we observe the complete opposite of this. Angular momentum is a conserved quantity, you don't just put the majority of the angular momentum in Jupiter and Saturn, but that is exactly what is observed. Astronomers want to ignore this problem because it is very simple and destroys the disk models and all the variants. Not only that, but there are other problems that are also ignored. The spinning disk models and theories are basically zombies. They are dead, but still walking around, infecting the minds of unsuspecting students at University and wikipedia readers who don't know any better.Trilliant (talk) 02:06, 17 May 2017 (UTC)

Any system that gravitationally contracts will do so eccentrically, so it must commence rotating as it is almost nearly impossible for all of its parts to be placed so perfectly that every part moves exactly on lines toward the mass center. Note that most Galaxies are spirals, and planets form concentric rings around them, and dwarf planets form from those rings. If you look at the Universe, everything ends up as spirals, rings, or spheres. 98.245.216.62 (talk) 20:02, 12 September 2020 (UTC)

Error?

"Eventually, after trillions more years, the Sun will finally cease to shine altogether, becoming a black dwarf." Seriously after trillions of years? --Hartz (talk) 05:58, 29 October 2012 (UTC)

True. Forgot to change that after the new reference. Serendi^podous 07:05, 29 October 2012 (UTC)

end of water on Earth

We say, "In one billion years' time, as the Sun's radiation output increases, its circumstellar habitable zone will move outwards, making the Earth's surface too hot for liquid water to exist there naturally. At this point, all life on land will become extinct. Evaporation of water, a potent greenhouse gas, from the oceans' surface could accelerate temperature increase, potentially ending all life on Earth even sooner."

From what I understand, that's not what we think will happen. In about a tenth that time, the increasing solar output will increase the height of water vapor in the atmosphere until it reaches the stratosphere, where it will dissociate and the hydrogen will be lost to space. In another 100My the oceans will be gone. Earth will thus loose its water long before surface temperatures would otherwise be too great for liquid water. — kwami (talk) 16:03, 3 October 2013 (UTC)

if that's true, a source would be really helpful. Most of the sources I have read say that the threat to life in hte next gyr is not ocean depletion, but CO2 starvation. Serendi^podous 17:16, 3 October 2013 (UTC)

Actually, I think you are correct. Look at Number 16, below, and Use Natural Logs to see how long it will take to double the Radius of the Sun, and how long it will take to double the Radius of the Earth. 98.245.216.62 (talk) 19:51, 12 September 2020 (UTC)

Early composition quibble

Isn't this statement in the article is a little off the mark: "The composition of this region with a mass just over that of the Sun was about the same as that of the Sun today..."?

A Wikipedia article on the sun says the sun in its lifetime has converted about 100 earth masses to energy. Solar nuclear reactions only convert about 0.7% of hydrogen mass to energy, so this means 14,000 earth masses worth of hydrogen have been fused to helium. The total mass of the sun is 333,000 earths, so during its 4.7 billion years as a main sequence star the sun must have converted 4.2% = (14,000/333,000) of its total mass from hydrogen to helium.

Don Fulton

 — Preceding unsigned comment added by 24.61.212.124 (talk) 20:42, 2 December 2013 (UTC) 

The conversion takes place in the core and the Sun is not mixed except the outer atmosphere (a few percent of the total mass). Thus, the spectroscopically determined composition of the Sun should be that of the lokal nebula, except for radioactive decay. --Rainald62 (talk) 21:50, 27 December 2018 (UTC)

The Sun would not be Fusing Hydrogen into Helium for all of its existence. It would commence the Fusing process when it became large enough ( larger than Jupiter is now ). Look at number 16 below and do some calculations based on the equations. I suspect that the Sun has only been Fusing Hydrogen into Helium during the last 2.354 Net Galactic Rotational Cycles while life on Earth was allowed to become large. Between 3.354 and 2.354 Net GRC's, the Earth was an Ice Ball ( Snow Ball Earth ) 812 Ma to 625 Ma. The Sun was not producing enough energy to warm the Earth Enough to keep the Oceans liquid.

The current age of the Sun should be about 5852.5 Million years old. The radius should be ( 1.003 453 602 + 0.000 000 024 X ( 5852.5 - 4544.4 ) ^ 5852.5 = ( 1.003 453 602 + 0.000 000 024 X ( 1308.4 ))^5852.5 = ( 1.003 485 004 ) ^ 5852.5 = 695,767,344.4 meter radius. The actual is 695,700 km ( close ).

So, 2.354 X 186.598 = 439.252 Ma Previously. 5852.5 - 439.252 = 5413.248 MY old. ( 1.003 453 602 + 0.000 000 024 X ( 5413.248 - 4544.4 )) ^ 5413.248 ( 1.003 453 602 + 0.000 000 024 X (868.848) ) ^ 5413.248 ( 1.003 474 454 ) ^ 5413.248 = 142,590,100.9 meter radius.

Making a simplified ratio: 695,700 km ( now ) / 142,590 km ( then ) = 4.879 to 1 The Sun is far bigger Now than it was when snow ball Earth Melted, and allowed larger life forms to evolve. So, is this reasonable??? 142,590 ( Sun, then ) / 69,911 ( Jupiter, Now ) = 2.04 to 1. Jupiter is currently creating more energy than it receives from the Sun, now, so when Jupiter more than doubles its current radius, it will become a Protostar, which will allow is ice covered moons to melt, and, evolve larger life forms too. Jupiter will double its radius in about 198 million years, the Earth in about 205 million years, and Mimas in about 215 million years. The Sun will double its radius in a lot less time than Jupiter does.

So, if the Sun has only been fusing Hydrogen into Helium for the last 439.2 million years out of 5852.5 million years, that is only about 439.2 / 5852.5 = 7.5 % of its total existence. So 0.075 X 14,000 = 1050.63. 1050.63/ 333,000 = 0.003155 to 1.0 or about 0.32 % of the Suns total mass has been converted to energy. Mike Clark, Golden, Colorado 98.245.216.62 (talk) 20:50, 12 September 2020 (UTC)

Nice model

The third paragraph states that "The position of the planets often shifted, and planets have switched places". However nowhere in the reference used (Gomes et al. 2005) is planetary orbit switching mentioned. What IS mentioned is that orbital periods of Jupiter and Saturn crossed their mean mean motion resonance (MMR) ratio of 1:2. Figure 2 of Gomes et al. (2005) indicates that at no point during the period responsible for the Late Heavy Bombardment did the orbits of the four outer planets switch <2>. If the orbits were changed during this chaotic period, then the authors must cite the correct reference.— Preceding unsigned comment added by Steven Corder (talk • contribs) 11:46, 26 August 2014‎ (UTC)

I suspect there were 2 planets that collided in the orbit of the Asteroid Belt just this side of 4,000 million years ago. The result of this collision was the late heavy bombardment, and differential growth rates either side of the Asteroid Belt. Beyond the Belt, Jupiter is larger than Saturn, and Uranus is larger than Neptune. This side of the Asteroid Belt, Earth is larger than Venus, and Mars is larger than Mercury. These are the 4 remaining planet pairs of the previous 5 planet pairs. The collision of the Asteroid Belt Pair would be a very slow differential velocity impact, but the large mass of the two planets provided lots of material to increase the growth rates of the closer planets significantly more than the growth rates of the planets that are farther away. The two planets closest to the asteroid belt, Mars and Jupiter both had a significant boost in their growth rates when compared to the others farther away from the belt. This is most evident in the size groupings of the Dwarf Planets. The 23.354 Net Galactic Rotational Cycle group is dominated by Mars with a radius of 3389.5 km, while the other four members of the group cluster between 2410, and 2634 km radius. Jupiter dominates its pair at 69,911, while Saturn is only 58,232 km. Moving farther out Uranus at 25,362 km is only slightly larger than Neptune at 24,622 km radius. This is similar to an exponential decay curve as distance increases away from the Asteroid Belt in both directions.

Since the mass of the Sun and all of the planets increases with elapsed time, all of the planets will be forced away from the Sun to higher and higher orbits from the Sun. So why did the Asteroid planets collide ? Was the Pair in the wrong order, or, were their orbits too elliptical so they eventually collided. This collision would provide enormous amounts of materials of an age that would be radiometrically similar in age, but slightly older than Earth's age, by + one Net Galactic Rotational Cycle of 186.598 million years.

The only way to test these Ideas is to use the 4,000 plus Exoplanets to see if they also form in pairs, or is size groupings. If this is true, then the Stars should also form in pairs, and size groupings. Interesting possibilities !

If the differential growth rate is true, then Planets must grow continuously,and/ or Intermittently over billions of years. That is, they tend to grow cyclically after their initial formation in a quiet Planetary Nebula. The Large a planet is, the older it is, and the more times it has orbited the galaxy. 98.245.216.62 (talk) 18:06, 31 May 2021 (UTC)

Redirection? Nothing's there!

Did you try taking a look at where it's now redirecting? A section here: I tried both reading through and searching on the entire page (CtrlF) - nothing EXPLAINING the concept or whatever which is at least definitely referrable. So you know what? Let's just make THIS a normal article: if somebody has something to say, or drop me a template if you have a good source or two — let us start it any way!.. Lincoln J. (talk) 11:59, 19 October 2015 (UTC)

Based on Lincoln J.'s editing history, I'm guessing that this might have something to do with this edit from 2008 in which Serendipodous turned Early bombardment phase into a redirect to Formation and evolution of the Solar System#Terrestrial planets. Apparently, the connection between these two is unclear and Lincoln J. would like to re-start the Early bombardment phase article. This could be a good idea if high quality sources are found. Alternatively, the Terrestrial planets section in this article could be edited to make the connection between it and the early bombardment phase clearer. What do others think? --Dodi 8238 (talk) 12:27, 19 October 2015 (UTC) [edited 16:06, 19 October 2015 (UTC)]

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Sun's beginning

In several places this article equates the "beginning" of the sun with the onset of nuclear fusion, which is also when it enters the main sequence. However, as far as I know, the official beginning of a star, including our sun, is when it transitions from a Protostar to a Pre-main-sequence star. Zyxwv99 (talk) 23:37, 19 March 2016 (UTC)

You should be correct. Fusion should not occur until the Sun had grown to a point that it is significantly larger than Jupiter is now. Since the Sun and Jupiter are only 4 Net Galactic Rotational cycles apart in age, and the Earth did not create large life forms until around 542 million years ago, the Sun, at that time, had already reached a size to warm up the Earth enough for life to evolve and make larger life forms in the oceans. Four Net Galactic Rotational Cycles is only 4 x 186.6 = 746.4 million years apart in both Cosmic, and Geologic age. The Snow ball Earth had its melt down about 3.354 x 186.6 million years ago = 625.8 Ma. So, some time between 746.4 million years ago, and 625.8 million years ago the Sun started cranking out the Energy from the Fusion of Hydrogen to Helium, and thus warmed up and melted Snowball Earth. This provided the opportunity for life forms to evolve into large types on the Ocean floor by 542 million years ago. By 400 million years ago the Ocean vegetation had colonized the land, and the Earth had trees, and by 360 million years ago the Earth had enormous insects on the land. Several look similar to the animals that were previously in the ocean.

The Evolution of the Sun from a Gas Giant to a Star with the associated increasing solar energy output is recorded in the geologic, and biologic evolution of the Earth since the meltdown of Snowball Earth. This process also hints at our future. Will the Earth continue to migrate away from the Sun at a rate that allows life to flourish on Earth's surface, or, will it gradually get hotter and hotter as the Sun's Energy output increases. The Earth is around 288 Kelvin, while Venus is 737 Kelvin, and Mars is around 205 Kelvin. As the Sun grows larger, it will produce more energy, but its increasing mass will move all the planets to higher orbits. I suspect that Venus lost this battle, and Earth will also eventually loose the same battle, and we will be left with Mars, and a very difficult engineering process to give Mars a real Moon with a radius of around 925 km, an Ocean, and a magnetic field, or we will all go extinct. 98.245.216.62 (talk) 19:19, 31 May 2021 (UTC)

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Problem with table

At the end of the article, the second-to-last event listed says the sun will cool to 5K in a quadrillion years, then to 9K in several quadrillion years. Obviously this is a mistake since the sun would not heat back up several K after the passage of that much time.

Bomb319 (talk) 13:55, 12 February 2017 (UTC)

There is another problem, 4.6 billion years - 10 billion years is not 4.6 billion years, it is 4.59 billion years — Preceding unsigned comment added by V620 Cephei (talk • contribs) 20:00, 8 May 2017 (UTC)

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Age of the nebula

I would guess that there is evidence constraining the duration between the SN seeding short-lived nuclides and the formation of the first minerals (dated 4.5682 Ga). --Rainald62 (talk) 22:01, 27 December 2018 (UTC)

If I remember correctly radio-nuclides can have their decay rates reset by melting. Look at the Videos by the Illinois Energy Prof. The 4.5682 Ga would then be a record of the last time that material was melted, highly compressed and had the materials Neutrons adjusted when forming a long lived radio-nuclide. This resets the clock for some material with very long half-lives. The short lived half life materials have long since used up all their half lives, and changed to more stable substances. The 4.5682 Ga is thus not the real age of the Nebula, but the last age of previous melting of some of the materials in the Nebula.

The Sun's age is approximately 5850.6 million years old, Jupiter, and Saturn are around 5104.2, Uranus and Neptune are around 4917.7, and Earth and Venus are about 4544.4. The smaller planets, and dwarf planets are younger still in groups that are about 186.6 million years younger for each group. You can find groups by grouping radius using similar numbers. There are only about 200 orbs to check, but it will become obvious which orbs go with which groups just by sorting by radius.

This is quite time consuming but it will provide insight into planetary growth sequences. Growth rates gradually increase, so the sequential time to double a planets radius gradually decreases with each successive growth cycle. The 19.354 X 186.6 MY dwarf planets double in about 215 or more million years. Earth's last doubling took about 205 million years, and the Sun is now doubling in about 195 million years.

This really messes up any attempt at linear growth equations, even equations using the Natural Log of the Radius do not plot as lines on log - log paper that are straight. They gradually curve up as time passes in millions of years. 98.245.216.62 (talk) 20:09, 31 May 2021 (UTC)

Saturn's rings

I just noticed the paragraph beginning with "Prior to the 2004 arrival of the Cassini–Huygens spacecraft, the rings of Saturn were widely thought to be much younger..." - isn't the opposite true? A simple Google search suggests that Cassini revealed the rings are actually surprisingly young. Any thoughts? Dayshade (talk) 02:41, 13 April 2019 (UTC)

Incorporate New Horizons findings

The New Horizons research team has published a series of articles that they claim revise our understanding of planetary formation. This is based on the findings of the New Horizons space probe, in particular the flyby of Arrokoth. As a non-expert, I can't comment on exactly what that means, or on how far we are from a consensus. But it seems to be a glaring omission that this isn't even mentioned here. I would expect a brief summary of the new results in this article, with more details in the accretion article. Can someone please fix that? StormWillLaugh (talk) 12:49, 2 March 2020 (UTC)

The Age of the Earth can be calculated from the rate that Moon moves away from the Earth, and there is more.

The Moon gradually spirals away from the Earth and the Earth - Moon Barycenter. It is based on a triple equality where the change in the distance divided by the distance is proportional to the change in the time divided by the time and is proportional to the change in the mass divide by the mass. This actually gives a number that is twice the age of the Earth, as the Earth is the older, and, more dominate member of the Earth - Moon pair. The annual change in the system is one part in 9.0888 E 9. Dividing this number by 2 gives an Earth Age of 4544.4 million years.

Planets that are younger than the Earth, are smaller in radius or diameter, and Planets that are older than the Earth are larger in diameter. Most of the planets, and dwarf planets are in size groupings of 2 to 8 per group. Planets grow in cycles that are 186.598 million years per cycle. It is easier to use 186.6 for approximations. The Earth uses a base number of 1.003 453 602, and its current radius in meters can be approximated by taking the base and raise it to the elapsed time. That is 1.003 453 602 ^ 4544.4 = 6,372,547.079 meters. Or if you are the picky type: 1.003 453 602 ^ 4544.395 = 6,372,437.228 meter radius. This is close to the Volumetric Mean Radius 6,371.0 Km. The Earth is about 24.354 Net Galactic Rotational Cycles old. that is 24.354 X 186.598 = 4544.4077 million years old. The Growth cycle, and the Extinction cycle are very close to the same: 66.043 Ma, 252.641, 439.239, 625.837,..... etc.

So if you want to know which cycle any planet, that is spherical, came from, you start at 19.354, and proceed up to 31.354 for the Sun. There are "sphericals " at 19.354, 20.354, 21.354, 22.354, 23.354, 24.354, 26.354, 27.354, and 31.354 Net GRC's. The Planets are missing at 25.354 ( Asteroid Belt, and the late Heavy bombardment ? ). Unfortunately the base gets smaller as you go back in time, and the base gets bigger as you move forward in time. The equation is referenced from Earth, and minus goes to younger, smaller planets, and plus is used for larger, older, planets, and the Sun. The equation is ( 1.003 453 602 -/+ 0.000 000 024 X delta t ) ^ AGE. For the Age, you subtract 186.598 million years per cycle, for smaller planets, and, you add 186.598 million years per cycle to estimate the size of larger planets. It works well for smaller planets, but the Gas Giants over estimate the age by up a hundred million years for Jupiter, but they are very close to the cycle for the Sun. This means the Gas Giants are actually thickly Gas enveloped rocky planets. The Earth will grow into a small Gas Giant some time in the next two Net Galactic Rotational Cycles Like Neptune, and Uranus.

The Growth rate is good reason why the Earth did not have large life forms until it was this side of 625.837 Ma. Large Life forms only have been on Earth for the last 2.354 Net GRC's out of 24.354 GRC's. That is less than 9.7 % of the total Earth elapsed time.

Correction: 625.837 divided by 186.598 = 3.353 931 982 or about 3.534 Net Galactic Rotational Cycles, not 2.354 Net G.R.C. ( MWC ). Corrected on May 31, 2021. 98.245.216.62 (talk) 19:29, 31 May 2021 (UTC)

For those who like calculations, use Both Wikipedia, and NASA Planet Fact Sheets to obtain data for about 26 to 30 planets. You should notice the patterns of growth if you group them by radius. Mike Clark, Golden, Colorado. 98.245.216.62 (talk) 19:45, 12 September 2020 (UTC)

Presolar howler

"Because of the conservation of angular momentum, the nebula spun faster thus creating more gravity." This awful sentence is so silly as to justify my calling it a 'howler'. Will someone please fix this? It is my understanding that the dynamics of particle collisions in a gravitationally collapsing nebula - without magnetic fields - will/must cause the eventual formation of a spiraling, collapsing, heating disk due to symmetry breaking in the random distribution of particle velocities. I make no claims about the significance of magnetic fields in protostellar disk formation, just admit I've never heard that claim before (but I am certainly not well informed in this subject). That is: "As the particles in the nebula collapsed towards its center under gravitational attraction, their velocities increased. Collisions (increasing the particles' temperatures) between particles changed the random (3D) distribution of particle trajectories and formed a spiraling, collapsing disk (~2D)." No "gravity" was created! (but the gravitational field (intensity) at the center increased as mass accumulated there. I am completely uncertain what the temperature (ionization state) of this cloud was, and when it reached (if it wasn't already) the temperature to ionize enough to form a strong magnetic field, AND what effect such a field had on the process going forward. But it should be clear that the electric current flow (from random to spiraling) is at least as much a result of particle in-flow and collision and preferential direction development as it is a (possible) cause.98.21.247.38 (talk) 11:45, 4 December 2020 (UTC)