[image: themis-1.jpg]
*Themis:*  *Order and Justice*
The Greek mythological realm seems to be the very last place one would look
for order, law and justice.  The capricious Olympians feel at liberty to
engage in the most atrocious acts and do so with impunity.  After all,
being both perpetually young and exempt from all punishments doesn't
generally encourage agreeable behaviors.      All the same, up in the
rarefied reaches of the Olympians one will encounter Themis, the
personification of order and justice.    In her right hand she wields a
broad sword with which she separates truth from falsehood. The left hand
holds a balance scale aloft, used to precisely balance justice and mercy,
ensuring that punishments are always condign and never gratuitous.
 Though she is never wrathful, those who attempt to defy Themis are
confronted by her furious cohort Nemesis, the dreaded goddess of
retribution.

The daughter of Ouranos and Gaia, Themis is a Titan, part of the generation
immediately preceding the gods.    Consequently, she is held in the
greatest esteem, even by the Olympians such as Hera and Zeus who have done
much to incur her displeasure.      Hera's regard for her actually veers
toward the reverential and she often refers to her as "Lady Themis."
Zeus, quite naturally, coupled with her on many occasions to sire the
Horae, goddesses of the seasons, Natura, goddess of the forest, the three
Fates, as well as Dike , goddess of justice; Eirene, the goddess of peace
and Eunomia, goddess of law and legislation.

Having been endowed with foresight, Themis built the famed Oracle at
Delphi, which she eventually bestowed on Apollo.  These predictive powers
serve her well when administering justice for she is well aware of each
person's destiny and true intentions.       The depiction of her
blindfolded, a modern instead of classical invention, is supposed to
reference her capacity to see beyond conventional sight.     Perhaps her
most important function is to regulate the affairs between men and women,
thereby ensuring the order of each household.   She also is said to enforce
the all-important relations between host and guests, the laws of Xenia.
Because of Themis, one would feel compelled to extend hospitality even to
mortal enemies if they happen to be within one's domicile.   Those who have
violated Xenia, notably Tantalus, who tried to feed visiting gods food made
from his own child, are subject to the harshest punishments.

One must both admire and sympathize with Themis..  While the other lofty
Olympians plot their petty intrigues and smite each other like petulant
children, Themis remains the truly august figure, serene, but austere.  A
calm center of a ceaseless maelstrom.

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2020-2021:  LXXVII


THE DAILY ASTRONOMER
Monday, January 24, 2o21
Exploratorium XII:  Sweltering Earth

______________________
Our apologies. We'll be off tomorrow,
but back on Wednesday.
______________________

*Location*
           Earth

*Time *
           1.1 billion years in the future

How much time do we truly have left on this verdant sphere?  Well, here I
am not referring to just us, but to all life on Earth.  At some level we
are all connected: from kangaroos to grasshoppers to hyacinths and coral
reefs. The one trait that ultimately binds us all together is our reliance
on the star Sol, affectionately known as the Sun.    Were the Sun to
somehow disappear, life would soon follow.     So, the question about our
remaining time on Earth is truly an issue pertaining to the Sun's
lifetime.  Or, is it?

Stellar astrophysicists are quite confident about the Sun's energy source:
thermonuclear fusion.      Presently, the Sun is converting hydrogen into
helium within its unfathomably hot core (27 million degrees F).  During
this process, some of the initial hydrogen is converted into pure energy.
Earth receives about one one billionth of this solar output.  Although that
percentage is minute, it is sufficient to sustain life on this planet.
Astrophysicists are also convinced that the Sun possesses enough hydrogen
reserves to maintain these core fusion reactions for the next five billion
years.     After exhausting this supply, the Sun will expand into the red
giant stage, in the process of which it will incinerate the inner two
planets and, perhaps, Earth, as well.  Even if our home planet is not
consumed, Earth will become so hot its surface shall become molten again.
 Based on this scenario, one would think that we Sun-dependent life forms
will have a mere five billion years to frolic about on Terra Firma before
doomsday. It turns out that we have far less time than that, about eighty
percent less., hence our presence here on Earth more than one billion years
in the future.

We came here at night so we wouldn't be able to see any life forms.   After
all, we have no way of knowing  what forms life will assume in such a
distant future.   We also made it cloudy because we can also not know the
stellar configurations in our sky.    The solar system has revolved around
the galaxy more than four times since our home time period.   Many of the
stars currently adorning our sky have perished.  Others are milling about
in far distant reaches of the Milky  Way.          The continents are
completely different, though how different remains highly speculative.
 Pangea Proxima, the next supercontinent to form after our home epoch, took
shape hundreds of millions of years ago and has already long since
fragmented.      Their arrangement 1.1 billion years remains unknown.

We do know, however, that the Sun is 10 percent more luminous than it was
during our home time period.      As the Sun fuses hydrogen, it accumulates
greater and greater helium stores.  This helium builds in the core and,
being a more massive material, increases the core temperature and
pressure.   These increases will cause the fusion reactions to "burn"
hotter.   [image: 1200px-Solar_evolution_(English).svg.png]

Another consequence of this fusion acceleration relates to the Sun's size.
As we can see in the above chart, the Sun's size will slowly increase over
time.   The increased size counterbalances the temperature increase so that
the Sun's effective temperature remains stable for the next few billion
years even as the luminosity increases as a consequence of the Sun's
expansion.

As the solar luminosity increases, so, too, will the solar constant,
defined as the amount of solar energy the planet receives per unit area.
The higher this value, the warmer the planet.   In 1.1 billion years, the
heat energy Earth receives will cause the atmosphere to moisten and perhaps
the oceans, themselves, will evaporate.   Life will be slowly but
inexorably expunged from the planet.

So, one might think it is rather a pointless expedition for us to venture
1.1 billion years in the future when we can't know any of the
constellations, or the continental configuration or even what life forms,
if any, are loitering about on Earth.   It is a dark and stormy night and
we are mired in darkness on this sweltering Earth.     Is there any point
to this exploration?

Well, it's so much warmer here than it is at home.

____________________________________
*Latest from the Hubble Space Telescope:*

[image: image.png]


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