Shrinking Sun

[The Kai]

Okay anyone else ever hear that the sun is decreasing in size every yeaR?? To set this up - A student was explaining how evolution is wrong. Supposedly if the earth was as old as evolutionists claim that it is the sun would have been out around like Jupiter.
This fine as a theory, but it all hinges of the shrinking sun theory and the Entropy theory
Thoughts....

 

[OUMoose]

Okay anyone else ever hear that the sun is decreasing in size every yeaR?? To set this up - A student was explaining how evolution is wrong. Supposedly if the earth was as old as evolutionists claim that it is the sun would have been out around like Jupiter.
This fine as a theory, but it all hinges of the shrinking sun theory and the Entropy theory
Thoughts....

Ummmm...

Yes, the sun is shrinking every year, though "shrinking" isn't really an appropriate term. Collapsing is the right one I think. The mass of energetic material blown out from the surface is larger than the amount trapped by its gravity. Though, it's not supposed to go to the next phase of it's life (red giant) for another couple billion years or so, give or take. Of course, at that point, it will envelope Mercury and Venus, and come so close to earth that anything not rock will be vaporized.

So, what does that have to do with evolution, or more importantly, astrophysics? Really have no idea what you're trying to say with this line:

Supposedly if the earth was as old as evolutionists claim that it is the sun would have been out around like Jupiter.

This student in question does know that ALL the planets (in this solar system) go around the sun, right?

EDIT: Misread your original statement, as I thought that line in question wasy trying to say the orbit would be different or something. I understand now. Sorry for the confusion. *humble bow*

 

[rutherford]

A quick google shows that in 1979 John Eddy and Aram Boornazian submitted a study that showed the sun was shrinking. This theory was quickly refined by other scientists to show a cycle of 76 years of shrinking and expansion.

By 1984 John Eddy had published another study which found that, from 1967 to 1980, there was an increase in the sun's diameter equivalent to 8 feet per hour. The behavior they found is extremely consistent with a 76-year cycle.


So, tell your student he's more than 20 years behind current scientific thinking.

 

[OUMoose]

Aye, I stand corrected. Went and looked up some Frequently Asked Questions about the Solar and Heliospheric Observatory (SOHO), and one of them addressed this sun expanding/contracting.

(you can find that page here)

What can we expect from the Sun in the future? Is it getting brighter or dimmer? Is it expanding or contracting?

(For an overview of the controversy over solar variability, I recommend John Gribbin's pre-SOHO book, Blinded by the Light: The Secret Life of the Sun, published in 1991) The Sun's brightness changes by only 0.1% between the minimum and maximum of a cycle. We do not have enough data to see any longer-term changes from cycle to cycle. However, the Sun has not changed drastically in recent decades. Models of solar evolution indicate that the Sun is gradually increasing in brightness at a rate of about 6% per billion years.

The Sun is not "currently" expanding or contracting to any measurable extent. I know of some observations made by an astronomer indicating that the Sun changes size over the 11 year solar cycle - decreasing in size from the maximum activity to the minimum and then increasing in size again as solar activity picks up again. Others have tried similar measurements and found no change in size. However, it is believed that in 4 to 5 billion years, the sun will expand as it fuses the last of its core hydrogen. The outer layers of gas will swallow some inner planets (possibly even the Earth). This is commonly referred to as the red giant phase. Then the inner parts of the Sun will stop fusing, contract, and become a white dwarf.

Check out these web sites for more on the lives of stars:
http://www.astronomynotes.com/evolutn/s2.htm
(Strobel's Astronomy Notes)
http://sohowww.nascom.nasa.gov/hotshots/1999_12_20/
(Total Solar Irradiance, 1978-1999

I still don't see the relevance on evolution, though.

 

[rutherford]

I still don't see the relevance on evolution, though.

Search terms "shrinking sun" should turn up some good stuff.

 

[The Kai]

I guess his point was that if evolution is believed that at one time the earth would have been envolped by the Sun. Given the idea that the sun is decreasing at a given rate you would therefore have to date the earth as a newer occurance

Another possibilty is that the orbits of the planets would expand to the diameter of the sun.
BTW, I can't really argue for this - I am not a believer and it was'nt my theory

 

[OUMoose]

Search terms "shrinking sun" should turn up some good stuff.

Ahhhh.. I get it now. Interesting theory, but yes, I think it was proven wrong. Thanks for the tip, Rutherford.