<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
<title></title>
</head>
<body bgcolor="#ffffff" text="#000000">
Ted Moffett wrote:
<blockquote
cite="midd03f69e0704251239x419c74d3k14fa4a014605d2fe@mail.gmail.com"
type="cite">
<div> </div>
<div>Paul et. al.</div>
<div> </div>
<div>Paul wrote:</div>
<div><br>
We've been around for a mere few million years, only the last few
thousand of which we've had the ability to write things down. This is
a small fraction of time for the Sun. Our observations of the Sun has
occurred over such a small timescale that we can basically say that
we've only seen it as a static observation.
</div>
<div>------</div>
<div>Good point, a point that applies in different ways to many
scientific issues...We could question whether gravity has always
operated as we observe, given the over 10 billion year history of the
universe, and our limited time scale of observation. Science makes
certain assumptions about how the universe operates, and the continuity
of the "laws of nature" is one of those assumptions, continuity over
time and in different places in the universe. This principle cannot be
"proved" without a doubt, as far as I know
</div>
<div> </div>
<div>But science does have its "time machines" to see into the past
before humans could make observations directly. The theory
of biological evolution is not based on just the life forms we have
observed evolving since Darwin, but on the evidence of fossils from
Earth's history, offering a kind of scientific "time machine" giving
information on life forms millions of years before humans walked the
planet. And in astronomy, we have observations of many different kinds
of stars from many different stages of evolution, providing a kind of
"time machine" to allow us by inference to look into our suns past and
future. The information we get from distant stars is in some ways like
a fossil (I don't intend this as an exact analogy), given that this
information sometimes took longer than the history of the human race to
reach us...It's mind boggling, but astronomy gathers information about
the universe dating from billions of years ago, even before our solar
system formed. <br>
</div>
</blockquote>
<br>
That's all true. I was thinking more along the lines of leaving a
kettle of water on the stove. You've been watching it for a few
minutes, and nothing bad has happened, but you notice it is a chaotic
environment and you can't really predict how exactly it's going to
boil. Maybe it will get more violent soon, maybe it won't. Of
course, a kettle of water boiling isn't going to easily harm us, but I
suspect that a small change from the Sun's perspective can really ruin
our day. Somewhere I found a clip of the Sun's surface as it moves.
It was pretty chaotic.<br>
<br>
It is amazing what scientists can do with our limited observations here
on Earth and in it's immediate vicinity. <br>
<br>
<blockquote
cite="midd03f69e0704251239x419c74d3k14fa4a014605d2fe@mail.gmail.com"
type="cite">
<div> </div>
<div>------</div>
<div>Paul wrote:<br>
<br>
I think the 0.8 billion year number you quoted is the time it will take
for the slow process of hydrogen fusion at the core to raise the
Earth's temperature 5%. <br>
------</div>
<div>The article I quoted on stellar evolution said that due to our
suns evolution the Earth would warm 5 degrees in 0.8 billion years, not
5%.</div>
</blockquote>
<br>
Five degrees, my bad.<br>
<br>
<blockquote
cite="midd03f69e0704251239x419c74d3k14fa4a014605d2fe@mail.gmail.com"
type="cite">
<div> </div>
<div>As to how reliable this figure is, I cannot say for sure, given
I have not surveyed the scientific consensus on this issue in this
field, and there may not be a consensus.</div>
<div> </div>
<div>I was wondering, can you offer some sources, articles, books, or
websites, for the information you were providing on stellar evolution?</div>
</blockquote>
<br>
Sure. I kind of made a mish-mash of a few sites. I'm searching for
them again, my apologies if I miss a few. Also, it's very likely that
I misunderstood much of what I read. I'm just getting started in this
area.<br>
<br>
<a class="moz-txt-link-freetext" href="http://zebu.uoregon.edu/~js/ast122/lectures/lec14.html">http://zebu.uoregon.edu/~js/ast122/lectures/lec14.html</a><br>
<a class="moz-txt-link-freetext" href="http://www.astronomynotes.com/evolutn/s5.htm">http://www.astronomynotes.com/evolutn/s5.htm</a><br>
<a class="moz-txt-link-freetext" href="http://www.astronomy.ohio-state.edu/~dhw/Intro/lec11_giants.ps">http://www.astronomy.ohio-state.edu/~dhw/Intro/lec11_giants.ps</a><br>
<a class="moz-txt-link-freetext" href="http://homepage.mac.com/dtrapp/eChem.f/labC3.html">http://homepage.mac.com/dtrapp/eChem.f/labC3.html</a><br>
<a class="moz-txt-link-freetext" href="http://www.maa.mhn.de/Scholar/star_evol.html">http://www.maa.mhn.de/Scholar/star_evol.html</a><br>
<a class="moz-txt-link-freetext" href="http://imagine.gsfc.nasa.gov/Videos/general/sun.avi">http://imagine.gsfc.nasa.gov/Videos/general/sun.avi</a><br>
<br>
Paul<br>
<blockquote
cite="midd03f69e0704251239x419c74d3k14fa4a014605d2fe@mail.gmail.com"
type="cite">
<div> </div>
<div>Ted Moffett</div>
<div><br>
Ted Moffett wrote: </div>
<div>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0px 0px 0px 0.8ex; padding-left: 1ex;">
<div text="#000000" bgcolor="#ffffff">
<blockquote
cite="http://midd03f69e0704231323w6c982dffh331e1366bbf68cff@mail.gmail.com"
type="cite">
<div><span class="e" id="q_11221edbe19be194_1">
<div> </div>
<div>All-</div>
<div> </div>
<div>Our sun will eventually cause fatal increases in Earth
temperature in its inevitable evolution into a red giant star. When
will these temperature impacts become significant? The article
below estimates that in 800 million years the sun's impact will raise
Earth temperatures by 5 degrees, the same amount predicted by some
global warming models for the human impact on global temperatures in
the next century: </div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)"
href="http://www.sussex.ac.uk/press_office/media/media191.pdf"
target="_blank">http://www.sussex.ac.uk/press_office/media/media191.pdf</a></div>
<div> </div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)"
href="http://72.14.253.104/search?q=cache:hAqjwfgBKT4J:www.sussex.ac.uk/press_office/media/media191.pdf+time+remaining+Earth+biosphere+sun+expansion&hl=en&ct=clnk&cd=6&gl=us"
target="_blank">
http://72.14.253.104/search?q=cache:hAqjwfgBKT4J:www.sussex.ac.uk/press_office/media/media191.pdf+time+remaining+Earth+biosphere+sun+expansion&hl=en&ct=clnk&cd=6&gl=us
</a></div>
<div> </div>
<div>"As a first application, let us ask how long it will take
for the temperature of the Earth to rise by 5 degrees (the rise
anticipated in the next century or so if the current human-induced
greenhouse effect continues unchecked). The equation predicts it will
take the evolving sun about about 0.8 billion years to produce this
rise- so human activity may be accelerating astronomical effects by a
factor of about 10 million."</div>
<div>------</div>
<div>This puts the highly doubtful claim that the current warming
trend on Earth is mostly due to increases in solar activity into
perspective, it seems.</div>
<div> </div>
<div>Ted Moffett</div>
<div> </div>
<div> </div>
</span></div>
<pre><hr size="4" width="90%">
=======================================================
List services made available by First Step Internet,
serving the communities of the Palouse since 1994.
<a onclick="return top.js.OpenExtLink(window,event,this)"
href="http://www.fsr.net/" target="_blank">http://www.fsr.net</a>
<a onclick="return top.js.OpenExtLink(window,event,this)"
href="mailto:Vision2020@moscow.com" target="_blank">mailto:Vision2020@moscow.com</a>
=======================================================</pre>
</blockquote>
<br>
</div>
<br>
=======================================================<br>
List services made available by First Step Internet,<br>
serving the communities of the Palouse since 1994.
<br>
<a onclick="return top.js.OpenExtLink(window,event,this)"
href="http://www.fsr.net/" target="_blank">http://www.fsr.net</a><br>
mailto:<a
onclick="return top.js.OpenExtLink(window,event,this)"
href="mailto:Vision2020@moscow.com">
Vision2020@moscow.com</a><br>
=======================================================<br>
</blockquote>
</div>
<br>
</blockquote>
<br>
</body>
</html>