THE SOU                                  TARIUM

207-7                           sm.maine.edu/planet

70 Falm                               nd, Maine 04103

43.66                              667° W 

Altitu                     sea level

Fo                   ary 1970

Jul                    765.5

2019                VIII     

THE DAILY ASTRONOMER

Thursday, October 10, 2019

October 2019 Night Sky Tour Part II

Look for the unseen!

Yes, well, that is utterly impossible, isn't it?   Perhaps not.   Remember that the apparently static night sky is boundless not only in it extent, but in its kinetic energy. Far more transpires beyond our view than occurs in our sights.      Look toward the northern region of Ophiuchus the Serpent Charmer.  This faint but enormous constellation covers much of the southwestern skyWell concealed within the inky black the Voyager I spacecraft moves away from its home planet at more than 33,000 miles per hour.   Although it was only launched in August 1977, Voyager 1is now more than 13 billion miles away and will continue moving inexorably out the solar system and well beyond.  The interplanetary probe is destined to become an interstellar emissary as it will come within 1.7 light years of the star AC +79 3888 in approximately 40,000 years.   Provided it doesn't collide with any careening objects or become ensnared by any other body's gravity, Voyager will continue to revolve around the galaxy for millions, or perhaps billions, of years.       Our most distant bottle in the cosmic sea.  

Well concealed within the northern region of Ophiuchus (Just under the "s" in the name label) soars Voyager 1, a spacecraft moving more than 33,000 miles an hour away from Earth and into the depths of interstellar space.

Much closer to home, approximately 10,000 satellites revolve around our planet. These artificial moons are scattered along all possible orbiting altitudes: from the low Earth orbit about 100 miles up to the rarefied regions above the geosynchronous orbital altitude of 26,200 miles.   A veritable swarm of orbiting spacecraft lurk above us at all times.   If a satellite is properly positioned relative to the Sun and an observer, it will be visible as a 'star like object' that appears to meander through the firmament.     Some dark sky observers devote their viewing sessions primarily to watching these satellites silently orbiting overhead vanishing and appearing as out of nowhere.

Peer into the eastern evening sky tonight and one will see the "kite tails" of Andromeda the chained princess attached to Pegasus' Great Square.    Look closely by the princess' leg and one will find a strange splotch of light wider across than the full moon, but not nearly as bright.   That small luminous patch is the great Andromeda Galaxy,  the closest of the large spirals to the Milky Way.     At a distance of 2.2 million light years, the Andromeda Galaxy (M31) is the most distant of the naked eye  celestial objects.      To look at this galaxy is to gaze upon our remote future, as Andromeda and the Milky Way are destined to "collide" within 4 billion years.   After a protracted sequence of collisions, these two galaxies will merge to form a megagalaxy of more than one trillion stars.   During their merger, both galaxies will expel millions of their stars into the unfathomably vast gulfs of intergalactic space..

Myriad sights to see....we regret that time, or, more accurately, our self-imposed limitations on time, allow us to focus on only a few..

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