THE SOUTHWORTH PLANETARIUM
70 Falmouth Street      Portland, Maine 04103
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43.6667° N    70.2667° W  Altitude:  10 feet below sea level Founded
January 1970
2021-2022: LXVI
"Embrace your must."


THE DAILY ASTRONOMER
Tuesday, January 18, 2022
The Mardi Gras Universe

We'll begin with an indefensibly inappropriate editorial comment.
Dismiss with fire and flourish the lamentably prevalent notion that the
Universe is just so much vacuum littered by accidents. This view, espoused
by such scientific luminaries as the brilliant Richard Dawkins and equally
gifted Steven Weinberg, is increasingly coming into vogue amongst the
intellectual elite, of which I am admittedly not a member. All the same,
this perception is utterly untenable. If astronomy has taught us anything
since the vague early days of monoliths, cave scribblings and papyrus maps,
it is that the Universe is both prodigiously creative and passionately
alive. Here, I am not suggesting the presence of a designing intelligence,
an issue I avoid like a swarm of flesh-eating plague spores. I am, however,
suggesting that every time we've attempted to drape a wet blanket over the
cosmos, the cosmos has vaporized it.

A century ago, many in the astronomical community insisted that the Milky
Way Galaxy encompassed the entire Universe. Most notably, on April 26,
1920, astronomers Harlow Shapley and Heber Curtis engaged in their famous
debate about this very topic. Shapley asserted that our galaxy was alone in
the cosmos. Curtis argued that it was one of many. Another astronomer,
Edwin Hubble, would soon after demonstrate that Curtis' view was the
correct one.

[image: shapley_curtis.jpg]
Harlow Shapley (L); Heber Curtis (R)

Later in the century, the notion of exo-planets, planets in orbit around
other stars, became a topic of fierce debate.   Yet again, many astronomers
insisted that the existence of planets, if not exactly unique to our solar
system, was still highly unusual.   They often cited as "proof" the belief
that planets could only form when two stars drew close enough together.
 The gasses stripped from both through tidal interactions could then
coalesce to form planets.       Considering the high improbability of such
encounters, planets would indeed be few and far between.    More than one
expert derided the earnest search for exo-planets as a vain pursuit and
waste of time.

Well.    In the mid-1990s, a planet was discovered around 51 Peg, the first
active star outside our solar system found to harbor planets.  (A planet
was discovered around a pulsar, a rapidly spinning supernova remnant,
earlier in the decade.)       As of today, astronomers have detected 4927
planets!
Based on these detections, astronomers estimate that our galaxy could
contain as many as one trillion planets.   To put that unfathomably large
number in context,  realize that one trillion seconds equals 32,000 years!
Planet formation is a likely consequence of star formation and might even
outnumber the stars by a significant margin.

The James Webb Space Telescope, which has been successfully deployed much
to the profound relief of  so many, will likely discover myriad other
planets and should also be able to study their atmospheres
to detect evidence of metabolic activity.      Of course, many dour
skeptics will argue that life is so exceedingly rare in the cosmos that
such searches should be abandoned.    After all, nothing has been found
yet.     Heavens.    That is akin to dipping a bucket in the ocean and
after examining its contents, declaring with dismay that  "all the whales
have gone extinct!"    The search has not yet yielded much because not only
does so much territory need to be explored, but we have only recently
obtained the means by which to conduct these searches.

If history is any indication, the cosmos will prove to be far more fertile
than we think.   Life most likely proliferates in the Milky Way.     That
we think otherwise is a result of our spatial isolation.  After all, the
Sun has about 330 cubic light years to itself.   All the same, we most
probably live in a sprawling galactic megalopolis, but just happen to be
confined -for the moment- to a small studio apartment within it.
Regard not only life's astounding diversity, as evidenced by the myriad
forms it assumes in sea, land and air, but also its stubborn resiliency.
Earth has taken quite a few beatings throughout its history and life, once
it became established, retained its hold despite this series of staggering
assaults.   There is no reason to suspect that such durability would be
limited only to Earth life. The fierce determination to  survive hostile
conditions and even thrive because of them must be a feature of vital
species everywhere.    Life forms at all stages of development, from
prokaryotic sludge to star-faring civilizations  exist in all directions
throughout the galactic star streams.  This conclusion we confidently draw
from what we've learned thus far about our Mardi Gras Universe: vibrantly
alive with color, incandescent with energy and more alive than we can even
imagine.




Tomorrow...the magic of the number 4800.



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