THE USM SOUTHWORTH PLANETARIUM
207-780-4249     www.usm.maine.edu/planet
70 Falmouth Street     Portland, Maine  04103
43.6667° N                   70.2667° W
Altitude:   10 feet below sea level
Founded January 1970
Julian date:  2458619.5
        "Where the outside inside is turned inside out."


THE DAILY ASTRONOMER
Thursday, May 16, 2019
In a Fern Forest in the Fimbulthul Stream

was* a planetarium the size of what on Earth would be considered a sizable
lake.  In fact what I assume was the floor was smooth as sheer ice and in
the low light one could only barely perceive its opposite edge just behind
a milky white nebulous reflection.    Of course, one hardly noticed the
shadowed periphery once the trail of dazzlingly bright, multicolored dots
appear.       Their first appearance was quite shocking, like an unexpected
detonation of laser light.    However, soon after their arrival, these dots
swiftly and gracefully glided along the surface.  Yet, they did not merely
move in a straight line like well trained soldiers.  Instead, some bobbed
up and down, while others appeared to float in various directions as though
the train was undergoing a slight dissipation.    After their third
appearance, I decided to follow them and had to maintain a steady pace to
keep them in sight.

As you might expect, those dots represented stars.   Planetariums
throughout the world and cosmos are so notorious for focusing principally
on stars that one wonders if they aren't horribly misnamed.**   These stars
were tracing and retracing paths that extended from one size of the
planetarium to another.  As I ran forward I realized to my shock that it
was an open planetarium: a mile high tower generated the star dots that
were so bright I could only barely perceive a semicircle of ivory light
protruding above the actual horizon.   Along the edges I saw towering
structures: amphitheater seating extending up many stories.   Everything
was deathly quiet as all the seats were unoccupied.   Apparently, this
system was automated and going through the motions despite the lack of any
audience, apart from myself.  (I would later learn that it was programmed
to turn on whenever any sentient being -or a close approximation -entered
the facility.     It gave me a warm feeling to know that the facility
probably burned through immense amounts of electricity just to entertain
me.)

The dots were of varying intensities as each one represented a star of a
particular brightness.    Apart from their speed, they were easy to follow
as one never lost sight of them, even when in the center of the planetarium
floor where I beheld an unfathomably vast sphere of stars all scintillating
like ice crystals in the luster of moonlight.     Even though the
inscription was naturally indecipherable,  I knew it to have been Omega
Centauri, one of the galaxy's richest and most populous globular clusters.
   And that meant that the dots moving rapidly across the floor were likely
representing the members of the Fimbulthul Stream!

No, I really can't pronounce that word, even though it was coined on Earth.
  That name derives from Nordic mythology and was one of the eleven rivers
that existed at the world's beginning.    The Fimbulthul in this context is
a stellar stream.   Those hardly garner the attention they deserve.  They
are collections, or associations, of stars orbiting a galaxy that were once
actually part of a globular cluster or dwarf galaxy.      There are many
orbiting around the Milky Way.     The Fimbulthul stream is actually quite
small and contains a few hundred stars.  (By contrast, the Monoceros Ring
wraps around the Milky Way three times and is 200,000 light years long.)
[image: 1024px-Fimbulthu_star_stream.png]


This remarkably large planetarium was* situated on a planet around one of
the stars comprising the Fimbulthul Stream.   Some of these stars move
through Earth's skies, but they are quite faint.      It is one of the many
stellar currents and eddies that meander through what seems to be a
quiescent night sky.        These stars were torn away from Omega Centauri
by tidal forces a long time ago.       In deep time, the stellar stream
will dissipate, as all associations do.

A bit breathless after chasing these dots across the vast floor, I just sat
and watched them cycle through a few more times:   replaying the dynamic
interplay of the Milky Way Galaxy and globular cluster as the latter loses
stars to the former.    I was wondering if I were going to actually
encounter anyone else, but would learn in time that during these excursions
to off world planetaria I would never be able to interact with anyone.
Only otherwise unoccupied planetaria would be accessible.  As it turns out,
that is all to the good.      Nobody would believe my stories about these
travels if I claimed to have ever met an alien.





*As the planetarium existed about 45,000 years ago, it seems logical to use
the past tense.

**(Oh, I should here explain that this was one of my first excursions to a
planetarium off world.   Yes, I don't blame you for your skepticism.   It
seems as though a small aperture along the floor leads to a conduit that
connects planetaria throughout not only the world, but galaxy as well.
The corridors have so far only directed me only to the truly immense
planetaria: a true delight for one who is ultra-sensitive and afflicted
with a troubling size preoccupation.)


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