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06/19/2001
Warming, Longevity and Slingshots
My last two columns have dealt with ammonia and with a
memory of a remark by one of my chemistry professors at
Dickinson College, located in Carlisle, Pennsylvania. My 55th
reunion at Dickinson prompted the remembrance. Going to a
55th college reunion is a joyous, yet sobering event. The
weather was ideal, Dickinson''s campus is still beautiful and the
new president, Bill Durden, is a remarkable individual.
Coincidentally, he''s a fraternity brother of our Lamb guy, Harry
Trumbore, who overlapped Durden at Dickinson back in the
early 1970s. The charismatic Durden combines both his
enthusiasm and passion for his alma mater with an exceptional
ability to convey those feelings to an audience. After hearing
one of his speeches, I felt that I had been in the presence of that
rare individual, a true leader. Fortunately, I resisted the urge
following his speech to give my life''s savings to the college! The
most enjoyable part of the reunion was, of course, getting
together with the dozen classmates from the class of 1946.
The sobering aspect of attending a 55th reunion is the fact that
too many of my classmates and some of their spouses are no
longer with us. The other side of that coin was the sizable
number of lively individuals sitting at the next table celebrating
their 65th reunion! There''s still hope!
Prior to starting this column, and not knowing what I would
write about, I''d finished eating a bowl of Breyer''s cherry vanilla
ice cream. This may sound totally irrelevant but I''ve mentioned
a couple times that Breyer''s ice cream literally saved my life -
making it possible for me to go to Dickinson College and now to
celebrate a 55th reunion. The ammonia connection is that the
Rakestraw''s ammonia plant blew up at the time I was picking up
the alternate choice, Breyer''s ice cream. My wife and I visited
the Rakestraw''s ice cream facility while on a break from my
reunion. I enjoyed a big dish of black walnut ice cream while
sitting outside in the parking lot on the old stone wall with a local
parent and her two boys. The ice cream was very good and
childhood memories were kindled.
But, back to the issue of longevity - that was really what we were
talking about, wasn''t it? After finishing the ice cream, we drove
down the alley and saw my family''s first house in Mechanicsburg
(we lived in four rented houses there). It is a duplex side-by-side
house. The other side at the time was occupied by the Spooners
(name changed to protect their privacy). As we approached the
house, I saw an elderly lady up the street talking to a young
mother and her children. I told my wife, "That lady looks like a
Spooner." I stopped the car and inquired as to the whereabouts,
if any, of any remaining Spooners. "I''m Ruth Spooner!" said the
lady. Well, Ruth was the daughter living with her parents when I
lived next door. She had grown to resemble her mother,
accounting for my recognition. I hadn''t seen her for almost 60
years! At 87, she still keeps up her flower garden, lives alone
and her 92-year-old brother comes over to mow the lawn! Their
substantial sized lot actually looks better than it did when I was a
kid. Now there''s more hope that I might make my 65th reunion!
But this is talking longevity on a local scale. As we''ve discussed
in past columns, some scientists worry about longevity on a
much grander scale. We''ve considered what would happen if
the human race somehow managed to survive the eons of time
until the universe had expanded and the stars had run out of fuel
and things got really, really cold. Actually, today''s problem is
just the opposite and we''ve seen this past week demonstrations
during Bush''s European visit. One object of the demonstrations
is our policy on global warming, which the scientific community
is generally convinced is caused by or exaggerated by human
activities. It''s certainly not my field of expertise, but the number
of papers in scientific journals supporting this conclusion is quite
impressive. An increase in the average temperature of the earth
of just a few degrees could have serious consequences for life as
we know it.
But there''s another warming trend, solar warming, that occupies
the thoughts of more long-range thinkers. This solar warming is,
as the name implies, the fact that our sun itself is getting hotter.
To the casual observer, the sun looks pretty simple - a hot yellow
ball. Of course, we''ve all seen pictures of sunspots and the sun''s
corona, observed during eclipses, but it''s much more complex.
Some awesome pictures of the sun at various wavelengths of
light can be seen in an article in the June 2001 issue of Scientific
American. These pictures show a sun just boiling with activity
and huge swirling "storms". The article, by Bhola Dwivedi and
Kenneth Phillips, is titled "The Paradox of the Sun''s Hot Corona"
and deals with a most unusual characteristic of our heavenly
benefactor. The sun''s energy that sustains us all originates in the
core of the sun through the same process of nuclear fusion used
in the hydrogen bomb. The temperature in the core is in the
neighborhood of 15 million degrees Kelvin. Don''t bother trying
to convert to Fahrenheit - it''s still ridiculously hot! As all that
energy wends its way to near the surface things cool down
remarkably to only about 6,000 kelvins. But here''s where things
get interesting. Closer to the surface, the temperature rises to
about 10,000 kelvins and, even more startling, out in space in the
corona it can get back to a million or so degrees! This article
describes how scientists now believe that this increase in
temperature is related to the presence of magnetic fields.
The explanation of this interesting phenomenon is pretty
complex and frankly I found it difficult to understand. Also,
since the astrophysicists don''t seem to agree unanimously about
the explanation, I have an excuse not to burden you or myself
with the details. So I turned to another very brief article by Mark
Garlick, a former astronomer, in the same issue of Scientific
American. This article is titled "Save the Earth", which sounded
like it might be of much more immediate concern. And it is - if
your time frame is a billion years or so. Here''s where the solar
warming comes in. According to Garlick, today''s sun is roughly
30 to 40 percent warmer than it was when it entered its current
state of relative stability some billions of years ago. Right now,
this degree of warmth seems pretty nicely suited for us humans
and other forms of life on our own planet. However, over the
next billion years, the sun will gradually get hotter and brighter
until it''s about 10 percent brighter than it is today. Boy, we''ll
really need that air conditioning!
One solution is to move to another planet, Mars being the closest
option. We discussed a few weeks ago some of the problems
getting to Mars - it''s a daunting challenge. But Garlick reports
that, at the University of California at Santa Cruz, a fellow by the
name of Donald Korycansky and his colleagues have found a
simpler answer. Let''s compensate for the increasing temperature
by moving out farther away from the sun! In fact, over a period
of 6 billion years, move it out beyond Mars'' current orbit!
The way that they propose to accomplish this feat is to use the
simple "slingshot" technique that we''ve used for managing the
journeys of some of our space probes. By controlling the orbit of
the probe just right we''ve been able to send the spacecraft close
enough to a planet for the planet''s gravity to attract the spacecraft
and speed it up in an orbit that slings it back out into space at an
faster speed. In fact, if memory serves me correctly, within the
past year or so some skeptics were concerned that one such space
probe was going to crash into us as it slingshotted around the
earth. Of course, nothing happened and the probe is out there
somewhere today headed for its destination. If you''re also a
skeptic, you might say, that this slingshot technique sounds like
we''re getting extra energy for nothing. Actually, what the
spacecraft picks up in energy results in an equal and opposite
change in the energy and momentum of the planet. But the
spacecraft is such a tiny object compared to a planet like earth
that we never even noticed the jolt.
Suppose though that instead of a wimpy spacecraft, we zip an
asteroid by the earth. In fact, let''s send a pretty sizeable asteroid,
about 60 miles in diameter and weighing zillions of tons, slinging
itself by the earth. If the position and orbit of this monster were
just right, the earth would move out to a new orbit farther from
the sun. Korycansky estimates that a move like this every 6,000
years would keep us cool enough to live a comfortable life.
According to Garlick, the approach employs technology that is
only decades away from being feasible. He doesn''t point out that
we have recently landed a spacecraft on an asteroid, Eros. Now
we just have to figure out how to steer it!
My own feeling is that it''s more urgent that we mount a major
effort to detect and deflect incoming space objects that actually
threaten to hit us! That seems to me more urgent than an
antimissile defense. An incoming asteroid or other space object
could make any worries about longevity moot - as the dinosaurs
found out!
On the other hand, if global warming is going to affect our lives
in this century, should we consider moving ourselves to a cooler
orbit in this century? I''m not sure I want to be around for that
experiment. Suppose NASA or its contractors foul up their units
as they did in one of the recent Mars probes. We may find the
asteroid on the wrong side of the earth and bumping us closer to
the sun! Or even crashing into us! Another thing, the article
didn''t mention what the moon is going to be doing as the earth
moves out. We sure wouldn''t want to lose it! And if we do
make it out near Mars, are we risking bumping into it?
I think I''ll just concentrate on making my 60th reunion!
Allen F. Bortrum
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