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From:
Edward Gleason <[log in to unmask]>
Reply To:
Edward Gleason <[log in to unmask]>
Date:
Tue, 29 Oct 2019 12:02:18 -0400
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THE SOUTHWORTH PLANETARIUM
207-780-4249   www.usm.maine.edu/planet
<http://www.google.com/url?q=http%3A%2F%2Fwww.usm.maine.edu%2Fplanet&sa=D&sntz=1&usg=AFQjCNHulkHuLP13bOG2PkNrPazsGWFs2A>
70 Falmouth Street   Portland, Maine 04103
43.6667° N                   70.2667° W
Altitude:  10 feet below sea level
Founded January 1970
Julian date: 2458785.16
2019-2020:  XLI
                 "Keeping a watchful eye on a complex sky"

THE DAILY ASTRONOMER
Tuesday, October 29, 2019
Our Eternal Components

One need only reflect on the lives of wit-disordered metaphysical
 philosophers to recognize the peril inherent in pondering eternity.   Our
otherwise miraculous minds seem ill equipped for such profound
contemplations.    We tend to derive comfort from the notion that all
things, including the biggest thing of all, draws to a complete ending just
as it arose from a specific beginning.       That we could be sitting,
driving, lying down or otherwise making a nuisance of ourselves in a cosmos
that will literally persist  eternally  is not only disquieting, but
alarming.          Could our comparatively brief lives be negligible
fragments of forever?

The notion of an eternal Universe, considered by philosophers both ancient
and modern, arose anew out of the Dark Energy Theory, dating from the mid
1990s:  the theory which asserts that a mysterious force operating over
cosmological distances could be accelerating the Universal expansion to
ever greater velocities.    Dark Energy theorists predicate this theory on
the observation that Type Ia Supernova are receding faster than they
should.      Type  Ia supernovae are explosions that occur when a white
dwarf companion of a giant star accumulates enough material from the giant
through tidal forces to cause the white dwarf to explode.   Remember
yesterday we mentioned that electron degeneracy -the mutual repulsion of
the white dwarf's electrons- prevents the white dwarf from collapsing under
its own gravity.    If the white dwarf's mass exceeds 1.4 solar masses, the
gravity will overwhelm the degeneracy pressure.  When the white dwarf
companion gathers enough gases to  surpass this limit, the white dwarf will
collapse and then explode.    Unlike Type II supernova that can result from
the explosions of many different types of highly massive stars,  the energy
release from each Type Ia supernova should be equal to the release of any
other such explosion.  For this reason, these consistently brilliant
explosions serve as reliable distance indicators on the vas intergalactic
scale.

[image: Type-Ia-supernova-e1416952264334.jpg]
*Type Ia Supernova:*   the distance markers over
vast reaches of deep space.

When the Big Bang Theory was first posited in the early 20th century,
scientists first considered time to have a specific beginning.  The main
question concerned the Universe's ultimate fate: would it expand forever or
would the matter within the cosmos exert an impeding force on the expansion
so as to either halt the expansion or, more likely, reverse it to produce
an implosion, playfully dubbed "the big crunch" that would precede the
expansion of another Universe.   The Dark Energy model, though not wholly
resolved, tells us that our is an eternal cosmos.

The implications of this theory also relate to you.  Yes, we mean you.
 Regard your fingertips or toes or any other part of the body in your view.
   What do you notice?  Or, more correctly, what don't you notice:  the
constituent atoms comprising those parts?  The carbon atoms, iron atoms,
and the myriad other molecules and cellular structures that conspire
together to form you.       These elements were, at one time, simpler: the
hydrogen and helium that crystallized from the radiant energy pervading the
infant Universe.      The carbon, iron, oxygen and other elements were
forged from the first generation of stars that transmuted the light
elements into heavier ones.    Eventually, the star that generated these
elements exploded as a Type II Supernova.  This explosion fused the
elements heavier than iron and then chemically enriched the surrounding
gaseous regions with these "metals" to produce the primordial cloud from
which the Sun and its attendant bodies formed.   These particles would
eventually become incorporated into the life forms: from the simplest
bacteria to the ultra-complex human. In other words, you.

We lose more than a billion cells an hour, only to have them replaced by
others.  Elements in; elements out.  The oxygen we inhale, the carbon
dioxide we exhale; the wicking away of our old selves; the reconstitution
of our new ones.    The elements that comprise us now will persist for
billions of years; just as they did for the aeons preceding our births.
In fact, if the Dark Energy theorists are to be believed, the Universe
could possibly persists forever, provided the acceleration won't dismantle
the Universe entire in a "big rip."    If the Universe holds together, we
are literally formed of eternal particles that, like the filaments of a
cirrus cloud, spent a rapid moment as us before moving on to other
endeavors.    We are therefore not only made of such little matter as to be
insubstantial, we are fleeting of duration and of ever changing form.

To think that looking up could result in such an inward perspective.
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