On
the evening of March 12th, Dr. Roy Houston, author of
the natural field guide Northwestern Gulf of California
and Adjacent Desert (available at the local bookstore)
delivered an interesting Astronomy 101 lecture that
covered everything from the birth of stars to small
biographies of our neighboring planets. The meeting
was held at the community center in Campo Virgel.
Dr. Houston, an astronomy enthusiast since his teens,
gave the talk as preparation for an open gathering to
be held the following evening at Campo Coloradito under
a sky that promised ideal conditions for stargazing.
Telescopes and binoculars were expected to attend as
well and Dr. Houston promised to bring his own optical
equipment and make it available for use.
Saturn seemed to be a popular focus of attention and
several who planned to attend the field trip the following
evening anticipated a memorable view of its rings. Saturn's
Ring Tilt for March 13th was only about 3.5 degrees.
Since January it has been narrowing and by June it will
be open only 1 degree. Then it begins to widen again,
reaching 10 degrees by the end of the year. Still, a
good telescope will show the open loop.
Dr.
Houston talked about the birth of stars, which emerge
from cradles of nebular gases that contract with exquisite
slowness under the force of their own gravity. After
showing a slide that illustrated the density of galactic
and nebular populations in deep space, he admitted to
a belief there had to be life somewhere out there. It
would appear Dr. Houston shares the conviction, along
with Jody Foster's character in the movie Contact,
that if life did not exist somewhere else in the universe,
it would be an awful waste of space.
During the talk, Dr. Houston explained the earth's
precession, which is the gradual shift in the orientation
of the earth's axis of rotation which, like the action
of a wobbling top, traces out a cone shape during a
cycle of about 26,000 years. Called the precession
of the equinoxes because the equinoxes move westward
along the ecliptic (the apparent yearly path the suns
takes) relative to fixed stars, it is the reason the
equinox and solstice, over time, move into different
members of the Zodiac. For example, the March equinox
passed out of the constellation Taurus into Aries circa
1865 BC. It then strolled into Pisces about 67 BC and
will move into Aquarius in the year 2597 AD.
Dr. Houston demystified the dense swathe of stars seen
overhead on moonless nights by invoking the image of
a great spiral galaxy and we, on a planet caught in
a back eddy of one of the spiraling arms, are merely
looking at the arm through its edge. The explanation
wasn't as poetic as the ancient Egyptians', who believed
the ribbon of stars overhead was a celestial river studded
with dark islands and that the gods plied the heavenly
waters on boats just as humans navigated the Nile. But
it was a lot more logical and didn't require getting
your knees dirty from unnecessary obeisance.
The talk was very informative and perhaps sparked interest
in a few who attended to drag out their unused telescopes
and Bushnells and turn them to the night sky. With a
bit of luck they might catch sight of someone in a linen
tunic punting a golden gondola through an atomized river
of stars.