Post by Radrook Admin on Sept 5, 2020 17:28:35 GMT -5
Sequence that leads a sun-like star to the Red Giant stage.
Contrary to first impressions, stars are not eternal but have a lifespan. How they change during that lifespan depends upon one very important thing, mass. The more massive the star, the faster it fuses at the core and shifts from fusing one element to the other. So the more massive a star, the shorter its lifespan. Stars that are similar to the sun fuse hydrogen into helium.
The byproduct of this fusion is called light, and it reaches us in approx eight minutes traveling at approx 186,000 miles per second and covering a distance of , 93,000,000 miles, ninety three million miles. Of course, with that light the sun loses a certain percentage of solar mass. For example, the sun is said to fuse approx 564 million tons of hydrogen per second, resulting in 559.7 million tons of helium produced.
Light as a byproduct constitutes a loss of mass of about 4.3 million tons per second. But that’s only 0.0000000000000000002 percent of the sun's entire mass. Which is still an astonishingly equivalent of 4 trillion Hiroshima bombs every second.
Lets see how this adds up over time:
To find the amount of mass lost in one minute in units of million tons, we simply multiply the 4.3 tons lost per second by 60 which represents the number of seconds in each minute. That would give us:
258 million tons lost to light every minute.
For the hour we multiply those 258 million tons by 60 minutes of the hour and we get
15,480 million tons every hour lost in light.
Per day we would multiply that figure of 15,480 million tons by twenty four representing the hours in each day and we would get:
371, 520 million tons lost to light every day.
For a month we would multiply that by approx 30.
11,145,600 million tons per month lost to light.
To get the yearly approximation, we multiply that figure by 12 representing each month of a year and we get.
133,747,200 million tons per year lost to light.
That is one-trillion, thirty-three million, seven-hundred and forty-seven-thousand, two-hundred million-tons per year lost to light. Remember, that is occurring at a pace equivalent to four trillion Hiroshima bombs per second over a period of one year.
To get the figure for ten years just add a zero to that number.
For a hundred years add two zeros
for a thousand add three zeroes.
10 years = 1,337,472,000 million tons lost to light. Which means that just ten years ago the sun was that much heavier.
100 years = 13,374,720,000 million tons lost to light
1000 years = 133,747,200,000 million tons lost to light
People living 1000 years ago were living under a sun that much heavier.
The rest of the fusion process goes into the production of helium, that stuff that causes balloons to rise and voices to rise when inhaled. Our sun is believed to have lasted five billion years with a predicted five billion more before it shifts from fusing hydrogen into helium to fusing helium into carbon. Once that happens, a sun-like star collapses, the core heats up again and causes it to expand gradually into what is called a red giant. Remember, this is what is thought to happen to all sun-like stars. Other stars of different masses, such as Red Dwarfs, which are far less massive, are believed to last far longer and end up differently.
Here is a synopsis of the sequence that leads a sun-like star to Red Giant stage.
1. Star fuses Hydrogen to helium in its core
2. Hydrogen into Helium fusion in Core ceases
3. Star compresses
4. Helium into oxygen and carbon fusion begins in core
5. A remaining shell Hydrogen surrounding the core commences to fuse Hydrogen to Helium
6. Core and shell fusion combined cause the star to expand enormously into a red giant. Any planets within that expansion are engulfed.
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7. Helium fusion at the core stops-outward pressure decreases
8. Gravity causes red giant star to collapse and shrink
9. Insufficient mass to fuse oxygen and Carbon into heavier element = inert fusionless core =========================================================
10. Helium shell around inert core begins fusion causing outward pressure and restoring the star to red giant size.
11. There is insufficient gravity to stop the outward 100,000 mph expansion. Star loses outer layers leaving a fusionless core behind.
12. That inert fusionless core is called a white dwarf. The core's gravity is insufficient to prevent that last stage leading to what is called a planetary nebula. Surrounded by this nebula is the star's former inert core now called a white dwarf star. Such a star is prevented from further collapse by electron resistance to additional gravitational compression. More massive stars that can overcome this resistance wind up as neutron stars or black holes.
White Dwarf www.eg.bucknell.edu/physics/astronomy/as102-
Reference
White Dwarf